Fan Convectors for Church Heating

Posted January 4, 2023

Fan convectors have been used to heat churches for many years. With many advantages we discuss why they are great as a church heating system. We also discuss how they are sometimes not the emitter for the application. Every building is unique and that’s why we have so many options to choose from because no one size fits all.

What is a fan convector?

A fan convector is essentially a coil that’s heated by hot water much like a radiator. However it also has a fan built into the unit. Usually a centrifugal fan. This blows air across the coil which sends warm air out into the room. This means they have a much great throw than a traditional radiator making them great for the application of churches. This is because they have a very high output condensed into a small unit because of the fans ability to distribute heat much further. Churches often have a large open spaces with high ceilings meaning heat is easily lost.

Why are fan convectors good for church heating?

Fan convectors have a very high outputs at full speed for the size of the unit. This means that they are much less intrusive space wise compared with radiators or standard heating coils. They also have the ability to slow down the fan speed or leave the fan off altogether. This makes them very versatile and a great for church heating as the fan can be used to heat up the church quickly then can slow down for a service so that it runs quietly in the background but can still keep the church up to temperature.

Fan convectors provide a very good distribution of heat compared to other forms of church heating. The fan can push the heat out as far as 12-15m depending on the make and size of the unit. This eliminates the age old problem of large churches only being warm at the perimeter and cold in the middle.

Fan convectors also allow for provision for future change of use in the building. For example if a church hall was partitioned to allow for different uses of the spaces the fan can be turned down or off. The TRV’s can also be adjusted. This means that the output is reduced so there is not requirement for a new heating system with smaller emitters. They are also unlikely to get in the way as they are very compact.

They are also low surface temperature (LST) which means that they are not hot to touch. this is because they have a smart metal casing around the coil. This makes them safe for small children as they are unlikely to burn themselves by touching them. This can make them more suitable for church heating than a lot of other options as many churches now hire their hall out to nursery groups.

Fan convectors can be set up to work with a reversed air flow. This is a simple modification by the manufacturer which essentially involves turning the fan upside down. What this does is cause the fan convector to draw in air from the top and push it out the bottom. The reason this is so successful in churches particularly where there are high ceilings is because it works with the natural thermal stratification blowing heat at low level across the floor. This is ensures that the system warms the people in the church and not just the church ceiling.

Disadvantages of Fan Convectors for Church Heating

We’ve covered the good points but no heating system is perfect for every application so its important the down sides are discussed.

Many churches are looking towards renewable heating now or at least some point in the future. It seems that the main solution for this currently is heat pumps. Unfortunately heat pumps are really work efficiently at a temperature of up to 55°C. Most heat pumps wont even get to an output higher than this although some are now coming on to the market. However they are not as efficient at the higher temperatures as they rely on the electric compressor and not the outside temperature to reach them. This is important as fan convectors are designed to work at a flow temperature of 80°C. They are inactive at lower temperatures as the coil is not hot enough to heat the air that the fan is blowing. This means that the fan will blow cool air into the room.

Whilst we are on that subject they also require a constant temperature circuit and not a variable temperature. This means that you cannot have a compensator for them. This is really a whole separate topic in itself, but to explain it very briefly: some heating systems have a compensator control which means they lower the temperature of the flow when its cooler outside to save energy as the heat emitters don’t need to be so hot to meet the heat loss. However as with the issue with heat pumps, this doesn’t work with fan convectors as they blow cool air.

The fan doesn’t come on until the heating flow is up to temperature. This means a longer warm up time if turning the heating system on from cold. this is to avoid blowing cold air into the room. However until the flow temperature is up to the set point and can bring the fan on, the fan convectors only provide a very low output.

A big disadvantage for many churches is the noise the fan convectors make. When a fan convector is on at full speed it can be quite noisy. This can be a particular nuisance in more echoey churches and make it hard to hear the service if you are sitting close to one. This can be worked round by having them sized correctly to provide the required output at low speed. They can also be lined with bara foam to reduce the noise further. However, this is definitely something to bear in mind when choosing a heating system for your church.