Fan Blog

Updates and news about Puravents range of drum fans, ventilator fans, wall mounted fans, fume extraction and destratification fans.

Heat Stress in Poultry- a financial disaster that can be avoided

Heat Stress in Poultry – What can you do?

Heat stress in poultry – What can you do?

Eleven of Plant Earth’s hottest years ever recorded have been in the last 20 years. This year the highest UK temperature ever was recorded at Cambridge – 38.7°C and the trend indicates records will be broken again and again in coming years.

Estimates vary, however it is widely assumed that each adult bird produces 10 – 20 watts of heat. On a hot day the roof of a poultry house can rise to 60°C due to the combined effects of the sun on the outside and rising heat from the poultry on the inside. If the body heat of a bird rises from 41°C (normal) to 45°C the bird will die.

Heat stress in poultry (and all other livestock production) is set to become a more frequent and an even more severe problem than it is today. Although it is a serious stock welfare and financial issue to livestock producers, it is also an issue with effects that can be minimized with preventative measures.

Where does the heat stress come from?

Apart from external heat sources the poultry produce a good deal of heat themselves as a result of metabolism – body maintenance, growth and egg production all produce heat which under normal weather conditions the heat is lost through :-

  • Radiation – heat is lost from the body of the bird by radiation provided the surrounding surfaces are at a lower temperature than the bird. Conversely hot roofs and walls will radiate heat towards the birds.
  • Convection – heat radiated from the bird will naturally rise towards he ceiling of the shed – where an outlet for the heat must be provided. Ventilation will assist this provided the airflow is high enough to break down the boundary layer of still air around the bird’s body.
  • Conduction – If the bird is in physical contact with a surface at a lower temperature than it’s body, heat will transfer to the cooler object.
  • External sources – Heat and humidity caused by the ambient weather conditions outside the poultry shed.

As well as sources of heat it is important to remember that heat stress results from a combination of temperature and humidity. The heat stress charts always pitch temperature on one scale against humidity on the other. For a given ambient temperature, the level of discomfort to the birds will be greater on high humidity days than if the humidity was lower.

What are the signs of heat stress in poultry?

  • Birds will pant at up to 230 times a minute in order to drive off heat in the form of water vapour – hence the need for plenty of cool drinking water for re-hydration. If the conditions are highly humid the panting of the bird is ineffective resulting in a very rapid increase in stress levels.

    Interior of a typical poultry shed

    Interior of a typical poultry shed

  • Raised wings in order to expose the featherless underwing area from which body heat (carried to the skin surface by blood vessels) may radiate.
  • Pale combs/wattles.
  • Lethargy.

In worst case:-

  • Diahorea.
  • Seizures/convulsions.

Other consequences of heat stress in poultry.

Unless measures are taken producers will see:-

  • Reduced growth rates in younger birds unable to react to rapid changes in temperature and humidity.

    Poultry discomfort chart by tempeture and humidity

    Poultry discomfort chart by temperature and humidity

  • Reduced egg production in more mature birds.
  • Darkening of the skin colour as more blood is diverted to the surface to combat the body heat rise.
  • Increased mortality in all birds but especially in the younger birds.

Measures to reduce heat stress in poultry

  • Make sure birds have cool, clean water.
  • Add electrolytes to water. Electrolytes help to balance the birds’ own electrolytes, plus they will drink more water.
  • Provide protection against direct sunshine and ensure the poultry house’s exterior structure is insulated and heat reflecting rather than heat absorbing
  • Reduce overcrowding and other forms of stress such as the presence of children, dogs, noise etc.
  • Provide adequate ventilation to remove the rising heat created by the flock.

Importance of good ventilation

Natural ventilation is not adequate in extreme circumstances. When high temperature is combined with high humidity all animals will naturally work to regulate their own body temperatures by measures such as sweating, panting, moving apart, reduction of food intake and activity etc.

It is important under extreme conditions to turn over the whole air volume of the shed regularly and also recirculate air within the shed when internal air distribution is poor.

Remebering that heat stress in poultry is in part a factor of humidity, it is important to realise that humidity levels will be higher inside the  poultry shed than outside. This is because the littering of the stock and thier sweating. Each bird delivers both heat and moisture load to the inside air. Although you can not change the humidity outside of the shed, with sufficient ventilation you can ensure that the effect of humidity on the heat stress level is no more than the outside ambient level.

Maximum_Ventialtion_rates_(m3_h_per_1000_birds) essential to prevention of heat stress in poultry

Maximum ventilation rates (m3/h per 1000 birds) – source DEFRA. The through flow of air based on these rates is essential to prevent heat stress in poultry

Main ventilation fans can be placed either:-

  • In a side wall preferably a North-Facing wall to push fresh air into the building – hot air would in this case exit the building through louvered  vents in the Apex or opposite end of the building.
  • In the Apex of the building to draw hot air out – fresh air would then enter through louvres in the walls (preferably North-Facing).
Box inlet fans - poultry house. An essential part of the shed infrastructrure to prevent heat stress in poultry

Internal view of Louvered Main Ventilation Fans

Suspended fan - part of the solution for heat stress in poultry

Suspended fan – poultry house

Puravent’s main recirculation ventilation fans are available in 3-blade or 5-blade versions, with or without inlet cones and in a wide variety of diameters (915mm to 140mm). We also offer panel fans range in diameter from 200mm to 920mm and in power from 60W to 1.8kW. They are also available in single phase (230v) or 3-phase (440v). All have IE2 or IE3 energy efficient motors.

Multifan with bird guard

Main ventilation fans – Optional cone for greater air flow

Puravent’s Internal recirculation fans should be placed  strategically around the shed so that fresh air does not short-circuit directly to the hot air outlets leaving discreet areas such as corners of rooms with no air turnover. These panel fans range in diameter from 200mm to 920mm ad in power from 60W to 1.8kW. They are also available in single phase (230v) or 3-phase (440v). This range covers air flows from 650m3/h through to 25,500m3/h.

V_flow_fans create disruption to linear flows down the poultry house

Typical V-Flo fan

V-flo fans can take air from above and below and throw it out to the sides of the shed. They are a great tool for the prevention of heat stress in poultry

V-Flo fan air flow patern

V-Flo fans in poultry application

As well as moving air through poultry buildings the air needs to be disrupted as it transits the building so that air movement reaches all of the corners and edges of the building.

Another method of minimising short-circuiting from inlet-fan to building-exhaust (thereby ensuring all the birds receive the benefit of the ventilation), is to create turbulence by the introduction of V- Flow fans. These ensure that air passing down the poultry house is driven out to the sides of the building as well as passing down the length of it.

Prevention of heat stress in poultry, is something that we know about and can help. To view the full range of fans visit our website www.puravent.co.uk or call us on 01729 824108 top discuss your specific requirements.

 

Intrinsically Safe Ventilation Fans

Intrinsically Safe Ventilation Fans

Ventilation in confined spaces or hazardous environments is a ‘no-brainer’ and reliable and safe equipment is essential. This is where intrinsically safe ventilation fans come into their own.

Intrinsically safe ventilation fans are ideal for work in confined spaces as well as in association with welding, concrete cutting, demolition. The same equipment may be used during remediation work following flooding to dry out buildings or simply provide fresh air to work areas as needed.

Intrinsically Safe Ventilation with Compressed Air

Clustajet Intrinsically Safe Air Mover

Clustajet Intrinsically Safe Air Mover Range

Puravent’s range of Clustajet of Intrinsically Safe Ventilation fans are as safe as it gets. With capacity ranging from 765 to 5,270m3/h, no moving parts or electric motor and driven by compressed air, they are ideal for use in confined spaces, and in damp or wet locations. The Clustajet range of intrinsically safe ventilation fans include 4 sizes ranging in diameter from 4″ to 12″.

12" Clustajet Intrinsically Safe Ventilator

12″ Clustajet Intrinsically Safe Ventilation fan… …or should it be called an air mover?

But to call them a fan is wrong, because they dont have any blades, so perhaps they are more accuratly described as ‘air movers’. Instead of fan blades they have eductor nozzles where the idea is that the compressed air is discharged from the nozzle in a way that maximised the air to air friction in the duct, and which induces the air in the duct to move in the same direction as the discharged compressed air.

The Clustajet units are generally used to extract air from confined spaces to allow fresh air to replace the extracted air, and where there are duct runs of more than 25m, we recommend a unit for each 25m of ducting.

With no moving parts to cause sparking, these units are safe for use in problem applications, such as with air laden with dangerous gases, dust or solvent vapours.

Puravent’s VAF intrinsically safe ventilation fans extends the operating range to 7,500m3/h and is the ideal in confined spaces or in zones where use of electricity is forbidden. Available in 300 and 400mm diameter, the double wall construction protects the inner casing giving extended product lifetime. The bodies on these intrinsically safe ventilation fans are made from a dual wall polythene rotational moulding allowing it to withstand the knocks normally found in industrial use – a common cause of failure with traditional steel cased fans.

VAF-400 Pneumatic Ventilation fan. Pneumatic ppwered fanThe 400mm diameter VAF-400P – FRL ventilator, weighs 13 kg and provides 7500 m3/h of air flow, driven by a pneumatic motor developing 1.1kw of power. It is built to provide maximum power where it is needed and it is the ideal large air flow  intrinsically safe ventilation fan. Intrinsically Safe Ventilation using a VAF300P-FRL pneumatic fan

The smaller variation on the theme is the VAF-300P – FRL intrinsically safe ventilation fan.  With 3400m3/hr of air flow it is a bit more portable that the 400mm unit and is suitable to ventilating smaller hazardous enclosed atmospheres

One of the big benefits of using compressed air to power a fan is that it is very, very controllable. Electrically driven ventilation fans are almost always an on/off affair, however the regulator valve on the compressed air inlet to the VAF pneumatic fans allows the airflow through the fan to be steplessly adjusted from 0 to maximum flow. It means that beyond the obvious applications in hazardous confined spaces, that they also have application in some process applications where fine adjustment of airflow is essential

It can out perform conventional metal bodied fans several times over. In fact we are so confident in the VAF-400’s quality then VAF offer it with an industry beating 10 YEAR warranty upgrade on the fan body.

Stacked 300mm dia. VAF Ventilators

Stacked 300mm dia. VAF Ventilators

VAF300_pneumatic fan and duct.  Intrinsically Safe Ventilation at its bestAll VAF models, both the pneumatic powered and the electrically powered versions can be stacked for ease of storage and to give maximum airflow from minimum floor space.

The high pressure capability of this fan make it very capable of use with up to 3 lengths of our 7.5m anti-static flexible ducting.

 

For further information and/ or help in sizing, please email us at puravent@gmail.com or call us on +44 (0)1729 824108

 

HVLS Destratification Fans

HVLS Destratification Fans – A Guide

High Volume Low Speed destratification fans (better known as HVLS destratification fans) are able to provide great improvements in working / customer animal environment and better operating conditions for many types of machinery. Due to their whisper-quiet operation (<60dBa) the Evel HVLS destratification fans are applicable across a wide range of environments including for example – restaurants, hotel lobbies, large open plan office places, atriums, warehouses, manufacturing environments and livestock buildings.

What is ‘stratification’ of air?

Evel HVLS destratification fans

HVLS Destratification Fans ranging from 2.5m to 7m diameter are available

Stratification of air is due to the fact that hot air rises, leading to the temperature at ceiling level being higher than at ground level. It is generally accepted that in rooms with stratified air, the temperature differential is typically 2-3°C per 5m height but can be as much as 1°C/m height in some circumstances.  In the worst case, this means that in a 10m high room the difference between temperature at floor level and ceiling level would be 10°C. To achieve a comfortable working environment of say 18°C therefore entails heating the ceiling to 28°C in this circumstance and the higher the ceiling the greater the potential temperature differential, and the greater the likely savings from implementing effective thermal destratification fans.

How do HVLS destratification fans work?

HVLS destratification fans take in the warmer ceiling air and transport it to the floor in a slow-moving column to create a better working environment and greatly reduce total energy consumption. In winter the most significant benefit is a considerable reduction in the cost of heating to create the optimum working/storage environment. During summer months HVLS destratification fans provide low-cost ventilation, reducing or eliminating the need for air conditioning.

When are HVLS destratification fans used?

Evel HVLS Farming 1

HVLS Destratification Fan in use in a livestock application

These fans come into their own in larger applications where there is an economic advantage to using HVLS fans rather than typically up to 7 smaller conventional destratification fans. The increased cost per fan of HVLS fans will be offset by lower installation costs (particularly power and control cabling), lower ongoing operating costs (due to far more efficient motors and responsive control systems) and lower future maintenance costs (due to lower speed and automated, variable speed operation).

Where are HVLS destratification fans used?

In retail or manufacturing situations it is necessary to maintain a comfortable environment to maximise customer enjoyment and / or employee productivity. In high-tech environments a stable controlled environment is required for efficient operation of electronic equipment.

In warehousing it is often necessary to maintain certain air quality standards including temperature and humidity in order to maintain the quality of the stored materials. Similar requirements apply to indoor sports arenas. HVLS destratification fans are ideal for such applications as they are able to respond rapidly to changing environmental conditions.

Enclosed or semi enclosed livestock buildings such as poultry sheds, livestock wintering buildings and cow milking parlours will enjoy the benefits of energy savings and enhanced productivity and improved animal welfare when HVLS destratification fans are put in place.

‘Evel’ range of HVLS destratification fans

All Evel HVLS destratification fans incorporate brushless motor technology with integrated inverter to give optimum efficiency and also allowing remote control and/or monitoring of more complex environments. Fans may be controlled remotely as individual units or may be grouped together as a system and controlled by a central controller.

  • The ‘WD’ range – This range is particularly though not exclusively applicable to the Hotel / Restaurant / Small Commercial markets. These have  5 ‘Selig’ profile fan blades with a diameters of  2.5 – 4 metres rotating at between 160 and 250rpm. These are suitable for ceiling heights up to 7 metres.
  • The ‘WZ’ range – This range is aimed at the Industrial / Large Commercial / Farming markets. These have  5 ‘Naca’ profile fan blades with a diameters of 2.5 – 7 metres rotating at between 38 and 250rpm. These are suitable for ceiling heights up to 12 metres.

Sizing your system

Selection of the most applicable size and the correct quantity of fans to gain maximum cost effectiveness in any particular situation is complex, because there are a number of other variables that conribute to the overall calculation.These include,

  • Ambient temperature outside
  • Materials of construction and how well insulated the building is
  • The efficiency of the heating system
  • The control accuracy of the heating system
  • The actual temperature differential pre destratification
  • The effectiveness of the destratification fans
  • The running costs of the destratification fans
  • The pricing structure of the running cost to your heating system

Help and advice

If you would like to find out more or to get advice on reaching an ideal air circulation system for your application then email us at puravent@gmail.com or call us on +44 (0)1729 824108

cool tortoise

Oscillating Wall Fans – keeping everyone cool

oscillating wall fans – not just for fitness studios


Cyclone oscillating wall fans
are a popular choice for creating air movement and ventilation in a variety of applications whether they be small or large rooms, sheds, industrial, or livestock applications. When the sun gets up, the heat gain on industrial and commercial buildings can be spectacular, making the building quite

oscillating wall fans

Heavy Duty Cyclone Oscillating wall fan.

When the outside temperature is in the 20’s, the temperature inside some buildings can easily reach into the 30’s. Although there is no legal minimum or maximum temperature in the work place in the UK, the HSE recommends a range between 13 and 30°C as being comfortable.

Most people find it uncomfortable to be in, or work in, an indoor environment much above 24°C. But the solution that increasingly being used is industrial wall mounted fans. When they are put in key positions to blow over crowded areas, or work stations, they can bring welcome relief to people who would otherwise be wilting in the heat. We find that they are very popular in shops, health clubs, gyms, and as we have recently discovered, in animal enclosures!

Wall mounted fans can be used in conjunction with open doors and windows to move air around the building and can, if cleverly placed, can induce air movement through the building, bringing cooler outside air in to replace the hot inside air. In addition to the cooler replacement air, people will feel air movement over their skin and thus feel cooler as evaporation from skin is increased.

 cyclone Oscillating wall mounted fans for Giant Galapagos Tortoises

tortoises appreciate cyclone wall mounted fans too

Dirk the Giant Galapagos Tortoise

We all can appreciate a bit of air movement in a warm environment, but as it turns out Giant Galapagos Tortoises also like some air movement to keep their living environment fresh.  Dirk the 70-year-old Giant Galapagos Tortoise is the largest of his kind in the UK. He happily resides at Crocodiles of the World in Oxfordshire, amongst other smaller reptiles, mammals, exotic birds, and 17 of the world’s 24 species of crocodiles. Dirk and the other Giant Galapagos Tortoises at Crocodiles of the World have Cyclone oscillating wall fans to ensure that the there is constant air movement round their enclosure which helps prevent stagnant air pockets, damp and rot.cyclone wall mounted fans

The spectacle of the crocodile feeding time is an understandably popular one and at busy times visitors may have a few minutes to wait before seeing Hugo and the other crocodiles. Luckily the waiting area for seeing the crocodile feeding has a number of Cyclone oscillating wall fans gently moving the air around to help visitors keep cool for those few moments of waiting. Once in to see the crocodiles feeding it is not a great idea to throw things in the enclosure as the management take a firm line on such antics.

Hugo loves cyclone wall mounted fans

Hugo the croc

Air circulation is one of the most important factors in keeping livestock and zoo animals. Whether it be cattle, pigs, poultry or indeed a Giant Galapagos Tortoise, proper movement of air can keep the enclosure healthy, and the animals comfortable. In stark contrast stagnant air mean that enclosures can be sources of infections caused by mould, damp, rotting vegetation and bedding.  An efficient cycle of moving air can keep moldy areas, and airborne infections at bay.

If you have any further queries on cyclone oscillating wall fans or their applications, please contact our UK-based office on 01729824108, or at info@puravent.co.uk.

If you want more information or to have a look for yourself at the animals mentioned here, take a further look at Crocodiles of the World’s website at https://www.crocodilesoftheworld.co.uk/

Giant Galapagos Tortoise loves oscillating wall fans

sweaty office worker

Case study in simple office cooling

Hot Office Problem
It’s not uncommon to have a south-facing window, and as much as we like the view from our office, there is a problem. In summer as the morning progresses we can feel the heat gain through our south-facing window as the sun reaches its zenith. For the rest of the day the office remains hot and can become stifling. Work rate decreases. Mistakes increase 😡

Office Cooling Solution Step 1
Rather than get an air conditioner to rattle away in the corner, we decided to lower the window blind before mid morning on the big window in the office and to use natural ventilation. So we opened the windows. Both windows are on the south side so whilst it was an improvement the air movement through the windows was limited 😐

Office Cooling Solution Step 2
The office has its access door from outside on the east side of the building. So we opened it and held it open with a bungee. Soon we had doors and windows banging shut as air rushed in or out of the office. Whilst the canister of bungees was out, it seemed like a good idea to use some more bits of hooked elastic to hold the internal doors and the toilet window open. Great. No more banging windows or doors and reasonable air flow though the office. With only a slight breeze outside we get outside air (which is always cooler than inside air,) flowing through the office :-)

But There Is Still A Problem
The recent hot weather has been from a ‘blocking high’. It’s because the jet stream is well above the UK that there is a large area of high pressure sitting over the British Isles. Not only does this high pressure give us clear blue skies and hot weather, it also means that there is precious little wind or even a light breeze. It means that our office does not have enough air moving through even with doors and windows open :-(

Office Cooling Solution Step 3
Seeing that a small part of our business is the supply of wall mounted fans it seemed like a good idea to use one of these fans in the office. It was the clever placement that made it really work. The office is long and narrow and the fan was mounted at one end near the door. With the oscillation function switched off it was left set at an angle which helps to pull air though the doorway from outside and blow the air through the length of the office. Bliss – fresh relatively cool air flowing through the office even when there is no breeze outside :-)

And here is a plan view of our office complete with ‘cheap as chips’ office cooling…

office cooling with natual ventilation and a wall mounted oscillating fan

Effective office cooling with natural ventilation and a wall mounted oscillating fan….Genius!

You to could probably work wonders cooling your work place with a wall mounted fan. Heres the line up that we offer…

The Cyclone 45T-W 18"Ø wall mounted oscillating fan

The Cyclone 45T-W 18″Ø wall mounted oscillating fan

The Cyclone 50W oscillating wall mounted fan

The Cyclone 50W 20″ Ø oscillating wall mounted fan

The Cyclone 650T-W 26"Ø oscillating wall mounted fan

The Cyclone 650T-W 26″Ø oscillating wall mounted fan

The Cyclone 750W 30"Ø oscillating wall mounted fan

The Cyclone 750W 30″Ø oscillating wall mounted fan

 

2017-09-12_1637

About 50Hz And 60Hz Machines

50Hz or 60Hz?

The majority of power outlets across the world operate 50Hz (220–240 V), ranging from majority of Europe and Asia, Africa, Australia, Russia, and South-Southern America. However, Northern America, and Nothern South America, operate a frequency of alternating current at 60Hz (100–127 V). To most, this is not new information, but how many can actually answer- why the difference?

The waveform of 230 volt, 50Hz compared with 110V, 60Hz

The waveform of 230 volt, 50Hz compared with 110V, 60Hz

When looking at the choice of grid frequency (assuming both voltage levels are the same), there can be seen to be no particular major advantages between either frequencies, with both being quite similar from an electrical perspective. Where they differ, however, is from a design perspective. Simply, 60Hz supplied to a motor makes it rotate faster compared to it being supplied by 50Hz.

It used to be easy, insofaras machines with motors would be able to work on either 50 or 60Hz, however as electric motors have developed over the years to become increasingly efficient, it seems that they are also more fussy about the frequancy or the supply. These days a machine that can run on both frequencies is a rarity and it is typical that they either run on 50Hz or 60Hz, but not both.

Historical Influences

Choices over frequencies does however have historical reasons. Early on in the history of electricity, the norm was set with Thomas Edison’s General Electric company distributing direct current (DC) electricity at 110 volts in the United States (U.S). With this, Nikola Tesla introduced three-phase alternating current (AC) at 240V. This allowed for three slightly out of phase alternating currents (AC) to combine and even out great variations in voltage occuring in AC electricity. With this, Tesla conclued that 60 cycles per second (60Hz) was the most effective frequency. However, due to safety reasons, reduced the voltage down to 120V. With this, 60Hz became the standard for the United States and Americas.

Over in Europe, German company AEG invested in generating electricity at 120V/ 50Hz instead of 60Hz to better fit their metric standard, and the result became the norm in mainland Europe. Post World War II, Europe switched to 220V for better efficiency in electrical transmission, and simulatensously, Great Britain changed from 60Hz to 50Hz to follow the European lead. What could have been an expensive switch-over was averted because few people possessed electrical appliances at this stage. However, at this stage a large portion of U.S consumers possessed electrical appliances and such a switch-over would not be viable. A comprimise was concluded with 240V being able to be introduced to a house where it could be split to 120V to power most appliances, whilst certain household appliances such as the electric stove and electric clothes dryer, would be powered at 240V.

Today, there are still a small minority of countries split between the two. For example, all of Japan runs on the same voltage, however the frequency differs from region to region. Eastern Japan (including Tokyo), uses 50Hz after purchasing electrical generators from the German company AEG in 1895. A year later, American company General Electric, provided 60Hz generators for cities in western Japan (including cities such as Osaka and Kyoto).

electricity_map jap

Japan’s (in)compatable power supply grid

Brazil faces a similar situation- despite the country running primarily on 60Hz, most states run between 110V and 127V AC electricity, whilst the northeast of the country run 220-240V (along with majority of the hotels spread all over the country)

Interested in products catered to 60Hz?

There seems to be a slight bend in the rule however. Majority of offshore vessels and platforms run off 60Hz, no matter where they originate or are manufactured. Ranging from oil rigs in the North Sea to the ships deployed by the Royal Navy (*excluding DC ships*), most of these run off 60Hz. The offshore market for 60Hz fans and other 60Hz machines has ensured that we have adjusted our product range to meet this requirement.

Here is a highlight of some of the products ranging from 60Hz fans, 60Hz fan heaters, 60Hz basket fans and 60Hz recirculation fans. The range of 60Hz that are either available in a 60Hz variant, or can be built to order for connection to a 60Hz supply.

60Hz fan options and 60Hz fan heaters available from stock

DVG-T/H Roof 60 Hz Fan

DVG-T/H Roof 60Hz Fan

DVV-EX Roof 60 Hz fan

DVV-T Roof fan

AJR jet 60 hz fan

60Hz AJR jet fan

BF-W Wall mounted 60 Hz fan

BF-W Wall mounted fan

Elektra 60Hz fan heater

Elektra 60Hz fan heater

Panther wall mounted fan heater can be supplied with a 60Hz fan

Panther wall mounted 60Hz fan heater

130cm basket 60 Hz fan

Vostermans Basket fan

Multifan Recirculation 60 hz fan

Multifan Recirculation fan

vflo fan available in 60hz

60Hz V FLo fan

water fed fan heaters available in 60 Hz

60Hz LTHW Unit Heater

AXCBF-EX ATEX certified bifurcated medium pressure axial 60 Hz fan

AXCBF-EX bifurcated axial fan

Multifan Tube mounting 60 Hz fan

Multifan Tube mounting fan

 

Machines which can be built to suit 60Hz supply

VRF range of desiccant dehumidifiers can be built as a 60Hz version

60Hz VRF Desiccant dehumidifier

MCM air conditioners are available in 60 Hz

60Hz MCM air conditioner

AD range of evaporative coolers can be built as 60Hz verions

60Hz Evaporative coolers

 

With that in mind, if you have any questions on purchasing a product that runs on 60Hz from this list or more from our range, (including its application), contact our specialists at info@puravent.co.uk or call our UK based office at 0845 6880112.

 

 

 

ATEX Fans

ATEX fans and Explosive Environments

Explosion Proof Fans

atexs. ATEX in explosive environments

Puravent’s range of ATEX fans

What is often misunderstood is what exactly is a ‘potentially explosive environment’, and where would you actually need an ATEX fan in an explosive environement, compared to a fan not designed for these sorts of applications. Firstly, explosive atmospheres can be occur in environments where there are flammable gases, mists or vapours, or combustible dusts. With enough of one of these substances mixed with sufficient oxygen in the air, the result is potentially explosive, needing nothing more than the spark from an electric motor or closing switch to cause an explosion. The costs associated to such an occurrence can cause not only significant damage, but also serious injuries, or loss of life. Therefore, the need to prevent releases of certain dangerous substances which can create explosive atmospheres and the need to prevent sources of ignition, are two important ways to reduce the risk. This can be done by using the correct equipment and understanding the dangers and regulations associated. Equipment used in ATEX zoned areas is required to be suitably certified for use the that particular category of zone. Likewise fans used for moving air or for pneumatic conveyance of powers are no different and also need to be certified.

Explosive Environments and Regulations

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) outlines the required duties for employers to enforce in order to eliminate or control the risks from explosive atmospheres in the workplace.

DSEAR defines an area where an explosive atmosphere may occur that requires special precautions to protect the health and safety of workers and enivornment as
hazardous. An area where an explosive atmosphere is not expected to occur in quantities that require such special precautions is deemed to be non-hazardous.

What is an Explosive Atmosphere?

According to DSEAR, an explosive atmosphere is identified as the mixture of dangerous substances (gases, vapours, mist or dust with air), under atmospheric conditions. With contact to ignition, combustion spreads to the entire unburned mixture and can result in explosion and harm to the workplace. These atmospheric conditions present are commonly referred to as ‘ambient temperatures and pressures’, which is temperatures of –20°C to 40°C and pressures of 0.8 to 1.1 bar.

Where can Explosive Atmospheres occur?

Typical ATEX zoned area in powder handling facility. ATEX fans

Typical ATEX zoned area in powder handling facility

  • Work places which produces and store foodstuffs (flour, cereals, grains, etc.) such as (powder silos, warehouses);
  • Farms;
  • Painting workshops (including vehicle spray painting workshops);
  • Carpentry workshops;
  • Petrochemical plants;
  • Fuel, gas or solvent storage and handling facilites
  • Laboritories and research facilites
  • Energy production plants (power stations);
  • Pumping stations;
  • Holds of cargo ships;
  • Within big fuel tanks/ drums and road tankers;

    refinery. ATEX fans

    Petrochemical facilities are typically covered with ATEX gas zones.

  • Underground and surface mines.

Employers hold the responsibility to classify these potentially explosives areas into zones. DSEAR provides a ‘ formula’ to the classification of each product. This can be broken down to see what environment the product is designed for. In regards to ATEX fans, the categories and ratings can be seen below. For further information on the protection ratings, refer to the 2002 Dangerous Substances and Explosive Atmospheres Regulations.

 

 

 

Identification for atex explosion proof fans

Zoning Definition and Equipment Suitability

Zone Description

Equipment Suitability

 0
 A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is present continuously or for long periods or frequently. 1G 
 1 A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally. 2G
 2 A place in which an explosive atmosphere consisting of a mixture with air of dangerous substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only. 3G
 20
 A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for long periods or frequently. 1D
 21 A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur in normal operation occasionally. 2D
 22 A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, will persist for a short period only. 3D


Types of Protection

Gas
Dust
TYPE ATEX CODE STANDARD
General Requirements EN 60079-0
Intrinsic Saftey Ex ia and ib EN 60079-11
Increased Saftey Ex e EN 60079-7
Flameproof Ex d EN 60079-1
Pressurisation Ex p EN 60079-2
Powder FIlling Ex q EN 60079-5
Encapsulation Ex ma and mb EN 60079-18
Oil Immersion Ex o EN 60079-6
Type n Ex n EN 60079-15
TYPE ATEX CODE Standard
General Requirements EN 61241-0:2006
Protection by Enclosures tD EN 61241-1:2004
Protection pD EN 61241-4:2006
Intrinsic Saftey iD EN 61241-11:2006
Encapsulation mD EN 61241-18:2004


Groups

I Electrical equipment intended for use in mines susceptible to firedamp~
II Electrical equipment intended for use in places with an explosive gas atmosphere other than group I
III Electrical equipment intended for use in places with an explosive dust atmosphere other than group I

Gas Group

IIA Propane
IIB Ethylene
IIC Hydrogen/ Acetylene

Dust Group

IIIA Combustible flyings
IIIB Non-conductive dust
IIIC Conductive dust

Level of Maximum Surface Temperature

T1 450°c
T2 300°c
T3 200°c
T4 135°c
T5 100°c
T6 85°c

With these ratings and categories in mind and when looking at certain ATEX explosion proof fans, it is easier to understand more about a product range and the ATEX zone type that the fan is certified and suited to.

Interested in the ATEX range?

Inline Ducted ATEX fans

KTEX Rectangular duct fan. ATEX fans

KTEX Rectangular duct ATEX fan

KTEX

II 2G Ex e IIB + H²  T3 Gb

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (Ex e) Increased saftey mechanisms
  • (IIB) Suited to applications with Ethylene
  • (H²) Also suitable for applications with Hydrogen
  • (T3) Max surface temperature of 200°c
  • (Gb) Gas equipment protection level
Roof EX fans

DVEX roof ATEX fan. ATEX fans

DVEX roof ATEX fan

DVEX
II 2G c Ex e IIB T3

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (Ex e) Increased saftey mechanisms
  • (IIB) Suited to applications with Ethylene
  • (T3) Max surface temperature of 200°c

DVV-EX Roof fan. ATEX fans

DVV-EX Roof ATEX fan

DVV-EX
II 2G c IIB T4

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (c) Increased constructional saftey mechanisms
  • (IIB) Suited to applications with Ethylene
  • (T4) Max surface temperature of 135°c
Medium Pressure Axial Fans

 

AXC-EX long cased ATEX axial fan. ATEX fans

AXC-EX long cased ATEX axial fan

AXC-EX
II 2G c Ex d IIC T4 Gb

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (c) Increased constructional saftey mechanisms
  • (Ex d) Flameproof
  • (IIC) Suited to applications with Hydrogen and Acetylene
  • (T4) Max surface temperature of 135°c
  • (Gb) Gas equipment protection level

 

AXCBF-EX ATEX certified bifurcated medium pressure axial fan. ATEX fans

AXCBF-EX ATEX certified bifurcated medium pressure axial fan

AXCBF-EX

II 2G c Ex de IIC T4 Gb

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (c) Increased constructional saftey mechanisms
  • (Ex de) Flameproof and increased saftey mechanisms
  • (IIC) Suited to applications with Hydrogen and Acetylene
  • (T4) Max surface temperature of 135°c
  • (Gb) Gas equipment protection level

 

Centrifugal Explosion Proof Fans

 

DKEX Radial fan. ATEX fans

DKEX Radial fan

DKEX

II 2G 3G Ex e T1 T2 T3

  • (II) Suitable for common surface application
  • (2G and 3G) Suitable for zone 1 and zone 2
  • (Ex e) Increased saftey mechanisms
  • (T1, T2, T3) Max surface temperature of
    either 450°c, 300°c, 200°c, respectively

 

ATEX centrifugal fan direct drive. ATEX fans

ATEX centrifugal fan direct drive

EX

II 2G 3G Ex de IIA IIB T1 T2 T3 Gb

  • (II) Suitable for common surface application
  • (2G and 3G) Suitable for zone 1 and zone 2
  • (Ex e) Flameproof and Increased saftey mechanisms
  • (IIA and IIB) Suited to applications with propane
    and ethylene
  • (T1, T2, T3) Max surface temperature of either
    450°c, 300°c, 200°c, respectively
Low Pressure Axial EX Fans

AW-EX Axial fan. ATEX fans

AW-EX Axial fan

AW-EX
II 2G c Ex e IIB T4 T3

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (c) Increased constructional saftey mechanisms
  • (Ex e) Flameproof and Increased saftey mechanisms
  • (IIB) Suited to applications with ethylene
  • (T4 or T3) Max surface temperature of either
    135°c, or 200°c, respectively
Plastic EX Fans

PRF Plastic radial fan. ATEX fans

PRF Plastic radial fan

PRF-EX

II 2G c Ex e IIB T3

  • (II) Suitable for common surface application
  • (2G) Suitable for zone 1
  • (c) Increased constructional saftey mechanisms
  • (Ex e) Flameproof and Increased saftey mechanisms
  • (IIB) Suited to applications with ethylene
  • (T3) Max surface temperature of 200°c

RVK-EX ATEX circular duct fan. ATEX in explosive environments

RVK-EX ATEX circular duct fan

RVK-EX
II 3G Ex d IIB T4

  • (II) Suitable for common surface application
  • (3G) Suitable for zone 2
  • (Ex d) Flameproof
  • (IIB) Suited to applications with Ethylene
  • (T4) Max surface temperature of 135°c

 

For further information on ATEX clasifications or products on the Puravent range, please visit the Puravent website. Or email further enquiries at info@puravent.co.uk

square destratification fan

Destratification Fan Energy Savings

Destratification Fan Energy Savings – The Performance Claims. 

There are many manufacturers of destratification fans these days as people wake up to the

Destratification Fan Energy Savings  - open bladed destratification fan

Conventional open bladed destratification fan

lost energy that lurks beneath their ceilings. But there is a problem – with so many products competing in the market for your custom, the technical and sales information being banded about is becoming fiendishly confusing. Some say that their destratification fan energy savings can as much as 20% of your heating costs, some say 30%, some even say 40 % savings.

So what is the truth of these claims and how do you compare  different models?

 The key advice here is to ignore completely the claims on destratification fan energy savings because they are all true…., in a sense.

Understanding Destratification Fan Energy Savings Potential

Destratification Fan Energy Savings  - Airius Destratification Fans - The most cost effective to operate

Airius destratification fan energy savings are impressive because they are very effective and use very little energy /m2 of floor area.

It is generally accepted that in rooms with stratified air, the temperature differential is typically 2-3°C per 5m hight, and as much as 1°C/m height.  Taking the largest differnetial rate as an example, this means that in a 10m high room the difference between temperature at floor level and ceiling level can be 10°C. The simple truth is that the higher the ceiling the greater the potential temperature differential, and therefore the greater the likely savings from implementing effective thermal destratification fans.

 

How Do Destratification Fans Save Energy

Destratification Fan Energy Savings  -  The helecentrifugal destratification fan

Helecentrifugal destratification fan – Nothing better for greenhouses

The way the savings come through is that when the destratification fans are installed and switched on, air is destratified and the heating system can be set to a lower temperature. Lets assume you have a 10m ceiling and the objective is to heat to 18°C at experienced level.

Assuming 1°C/m as differance (for easy maths), then the air at the air at ceiling level could easily be 28°C. The average of these temperatures is 23°C. In order to achieve the 18°C target, the heating systems needs to work to achieve a 23°C average temperature. The theory is that the cost difference between heating to 18°C, and heating to 23°C is the potential saving that you can achieve, by using destratification fans.

Destratification Fan Energy Savings  - Ssquare destratification fan

Modern square cased destratification fans

Now whether that cost saving is 10, 20, 30 or 40% depends on a whole host of factors, but before discussing that it is worth reflecting that the potential cost saving increases as the ceiling height increases. What this means is that leaving aside the other factors in the potential savings equation, that is very unlikely that 40% heating cost saving will be achieved if your ceiling height is only 3.5m. If on the other hand you have 30m roof line ceiling then 40% heating cost saving is much more likely.

The other factors that determine the extent of the destratification fan energy savings include,

  • Ambient temperature outside
  • Materials of construction and how well insulated the building is
  • The efficiency of the heating system
  • The control accuracy of the heating system
  • The actual temperature differential pre destratification
  • The effectiveness of the destratification fans
  • The running costs of the destratification fans
  • The pricing structure of the running cost to your heating system

Soucing Destratification Fans? – A Little Advice. 

So beware the destratification fan energy savings claims of the manufacturers, but instead endeavor to understand the source and factors influencing the potential savings. The key thing though is  to select destratification fans based on their destratification performance and effectiveness. But before launching into selecting the destratification fan with the highest airflow in the belief that this is the measure of performance, please take a moment to read our guide on destratification fans, because it is not quite as straight forward as that.

 

 

 

vflo fan

Air Circulation Fans

It’s not only people that appreciate the movement of air. Many plants, livestock and processes also rely on air movement. Whist we may appreciate the economic sense in destratifying air to lower heating bills, we may not realise that traditional destratification fans are not always the best way to move air uniformally about in a room. Air circulation fans which are used for generally moving air around in a space come in many guises and we have covered basket fans and oscillating wall mounted fans in previous blogs. In this blog we will look at air circulation fans of a type otherwise known as V Flo fans and their ideal application in green houses, poultry sheds and drying processes.

V Flo  air circulation fans

V Flo air circulation fans have a conical-shaped deflector which is Ideal for creating a coanda air flow that makes a uniform air circulation pattern.

Introducing V Flo Air Circulation Fans

There are plenty of air circulation fans available, some fixed and some that oscillate, however there is only one fan that is fixed and designed specifically for large open buildings with relatively low roofs and that is the V Flo. Although it is a normal axial fan pulling air vertically upwards, what makes this air circulation fan unique is the shallow conical defector. The effect of this is to turn the discharged air and to spread it out horizontally so that a coander air flow pattern is established in the building. Like all fans their effectiveness depends upon their size and airflow and they can only be effective over a limited area. For larger buildings several V Flo air circulation fans may need to be used.

The Advantages of V Flo Air Circulation Fans

The principle advantage that comes with V Flo air circulation fans is increased productivity because uniform air movement within a building ensures that there is an air current, even in the corners and at floor level, that prevents damp static air pockets that can harbour disease, and prevent drying.

Commercial Green Houses Poultry Housing Drying Processes
  • Prevention of static air pockets that could harbour lingering dampness around plant foliage
  • Dramatically lowered plant losses due to rot and disease
  • Movement of foliage thought to toughen young plants
  • Lowered heating energy costs
  • Even movement of fresh air through the building ensuring no pockets of hot air
  • Minimization of stock loses due to foot and leg problems casued by damp air pockets and damp litter
  • Control of humidity at the litter level
  • Increased comfort for the birds
  • Even air movement ensures even drying of product
  • Reduced drying times enabling higher product throughput and productivity
  • Elimination of high humidity static air pockets.
  • Lowered energy costs

 

V Flo air circulation fans - the air flow pattern

Air is moved in a coanda air flow pattern bringing air vertically up into the fan where it is then thrown horizontally outwards. Air on the underside of the roof is also moved within this pattern by the friction of the air from the fan pulling the air above along with it.

 

Obviously if any of the above is of any interest and you would like to find out more or even get some help on reaching an ideal air circulation system for your application then call us. 01729 824108

650W walll mounted fan

So You Need A Wall Mounted Fan …

Wall Mounted Fans and its Application

There is a world of difference between the wall mounted oscillating fans that you might come across for domestic use and the type of wall mounted fans that are available for commercial use.

A small wall mounted fan - Ok for your conservatory but too small and flimsy for commercial and industrial applications

A small wall mounted fan – Ok for your conservatory but too small and flimsy for commercial and industrial applications

A domestic wall mounted fan will typically be 12″ Ø, made of plastic or lightweight metal with a chrome finish and have a remote control. Not the sort of kit that is much use in a commercial application where something altogether larger and more robust is called for.

So if domestic fans are too small and puny, what kind of wall mounted fan do you need for those commercial and industrial applications?

650W walll mounted fan

A proper industrial wall mounted fan, this one is 26″Ø and heavy-duty. Great for factories, and larger retail spaces, but too large for your conservatory.

Consider…

Fan Size Occupied rooms in commercial buildings are typically quite large and a wall mounted fan in such a setting needs to be correspondingly large in order to move sufficient air around the room to get cooling effect. Generally any fan less than 18″ Ø will be too small for commercial applications and you may need to use a larger fan, possibly as large as 30″Ø
Oscillation Although in most applications you need your wall mounted fan to oscillate, it is also very useful to be able to set the fan in a particular direction. On good fans this is easy – let it oscillate until it reaches the point in its travel where you want it to point and disengage the oscillation function.
Fan Speeds Look for at least 3 fan speeds. With increased speed comes increased noise. On the hottest days you may be prepared to tolerate the extra noise and air flow to get the desired cooling effect, however it is good to be able to turn it down to just enough, when it’s not so warm.
Controlswall mounted fan control Remote controls … bad idea. In work places remote controls are almost certainly going to get lost and get flat batteries.We recommend that the controls are on-board the fan, and ideally supplemented with pull cords. Pull cords or chains to operate the controls are useful because it means that the strings hang down lower than the fan itself meaning that it can be within reach from floor level even if the fan itself is not.Look for the controls themselves to be robust and have a positive clunky feel. Cheap ones break!There should be 2 pull cords which will give you control of on/off, fan speed and oscillation function
Build Quality The fan should have a bit of weight to it and feel solid. If fan ‘A’ is 20″Ø and weighs say 4kg but fan ‘B’ also is 20″ Ø and is 8kg, then its easy. The heaviest fan ‘B’ is the most robust and the one to go for. Ideally go for metal cased motors, and metal protective cage round the fan blades. The fan blades themselves are actually better being in moulded plastic rather than metal because this means they are less prone to damage and if impacted tend to spring back to their previous shape.
Fixing to Wall A good wall mounted fan should have a heavy-duty fixing plate with at least 4 points for screw fixing. This is important because the complete weight of the fan goes through the plate to the wall so it need to be tough enough not to flex under the weight of the fan and motor even if it gets knocked,
Pitch Setting A wall mounted fan needs to have the ability to have its angle of operation set, so that you can set it to point for horizontal discharge,  or say, set it to a lower angle so that the air flow is discharged downwards at an angle.

Needless to say the Puravent wall mounted range does all this and more…

Puravent’s Range of Wall Mounted Fans

45W industrial wall mounted fan 45W industrial wall mounted fan 650W walll mounted fan 650W walll mounted fan

Cyclone 45T -W
18″ Ø

Cyclone 50W
20″ Ø

Cyclone DF650T – W
26″Ø Also available in 110V
Cyclone 750W
30″Ø

 

 

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