Frequently Asked Questions

Q.

Are the cast iron radiators from Feature Radiators compatible with my system?

All of our radiators are compatible with normal central heating systems and have British Standard fittings. On an existing system you can replace all the radiators or just the ones you want.

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Q.

Are cast iron radiators as efficient to run as regular radiators?

Yes.  They are no more expensive to run than regular radiators.  Cast iron is a very efficient heat emitter.  Cast iron also holds heat extremely well, which means that the radiators stay warm long after the central heating has been turned off.  It is for this reason that radiators made of cast iron are arguably more cost effective than regular radiators.

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Q.

Who will install my radiator?

Our radiators can be installed by any plumber or competent DIY enthusiast.  They are compatible with 15mm (1/2") or 22mm (3/4") valves from all DIY stores or local plumbers merchant, though we would strongly recommend our own attractive alternatives which are in keeping with the radiator itself.

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Q.

How do I calculate the correct size of a radiator for a room?

Radiator outputs on this site are all quoted in Watts, you may prefer to work in British Thermal Units, so the conversion factor is included in the this FAQ section. 
A heating engineer will be able to very accurately calculate the exact room requirements, however the following calculation gives a very good approximation (when in doubt choose a larger radiator than required and fit a thermostatic radiator valve to control the room temperature).

Find the volume of the room in cubic metres (length x width x height) 

Lounges and dining rooms multiply by 50.
Bedrooms multiply by 40. 
Common areas and kitchens multiply by 30.
Bathrooms multiply by 90.  

For rooms facing north add 15%. 
For French windows add 20%. 
For double glazing deduct 10%.
For very exposed sites, or very cold weather add 10%

This will give you the output of any radiator in Watts. Multiply this by 3.412 to give the requirement in BTU's.

We will let you know the heat output of any of our radiators, so you can choose a single radiator or a number of radiators whose outputs add up to the heat you need.

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Q.

The radiator I want hasn't got enough output for my room, what can I do?

You need to add another radiator into the room to provide the shortfall in output required. You can use any type of radiator to do this, we supply aluminium radiators (Decoral 10) which, for their size, have the greatest output, and are a popular radiator style.

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Q.

I want to install aluminium radiators is there anything I need to know?

Aluminium radiators are installed in exactly the same way as steel or cast iron ones, the only difference is that a different inhibitor must be used to avoid corrosion. Suitable inhibitors are now easily available from most plumbers merchants. Examples of our aluminium radiators are the Motus and Decoral 10.

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Q.

How do I convert from BTUs to Watts?

Divide by 3.412.

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Q.

How do I convert from Watts to BTUs?

Multiply by 3.412.

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Q.

Where should I position radiators?

Radiators work best in the coldest part of the room. Ideally this will be on an outside wall, usually under a window where the cold air drops to the floor. If you have long curtains or don't want to put a radiator beneath a window, it is perfectly acceptable to place one where it will suit your furnishing arrangements.
If you haven't got enough room for the right-sized radiator, you can choose two smaller ones and spread the heat more evenly.

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Q.

Can I use microbore pipework?

Yes, but on really big cast iron radiators (over 3500 Watts) it can prove problematic on balancing the central heating system, if in doubt ask your plumber.

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Q.

How do I fit valves?

Wrap at least five turns of PTFE tape around the threaded tails of the valves and screw them into the radiator. Make sure the PTFE tape stays on the thread rather than just running along it as you tighten. If it does run, undo the valve and roughen the thread slightly with a hacksaw blade then re-tape the thread. Some of our valves have parallel threads which means that they never tighten against a stop like traditional valves so more PTFE than usual is required - we recommend the use of gas type PTFE which is much thicker than the standard. The advantage of parallel threads is that they fit the same depth on all radiators so giving pipe centres is more accurate and also the threads are completely hidden inside the end of the radiator.

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Q.

Valves are sold in pairs, what is the other valve for?

The one valve is the temperature control, the other is called a lockshield valve and is used to balance the radiators in a system so that they all heat up at roughly the same rate. Simply put the radiator closest to the boiler if left unchecked would heat up much more quickly than one sited at the other end of the house, so the lockshield valve should be more open the further away from the boiler and more closed closer to the boiler.

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Q.

What is the difference between a TRV (Thermostatic Radiator Valve) and a manual one?

The TRV controls the room temperature by sensing the room air temperature and automatically opening and closing the flow to the radiator to maintain a preset temperature. A manual valve controls the temperature of the radiator regardless of how warm the room is already. On large radiators (above 1800 Watts, or where the radiator is oversized for the room) we recommend TRVs because they save you having to get up to turn the radiator up and down, but they are not essential.

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Q.

Do cast iron radiators take longer to warm up than standard radiators?

Yes, however, because there is a lot of mass with cast iron, the radiators have the advantage of staying warm long after the central heating has been turned off.  This means that the changes in temperature in a room heated with radiators made of cast iron are more gentle than those in a room heated with regular radiators. Most people tend to run their central heating twice per day, once in the morning and then again at night, if a third short period is added into the middle of these two times then the warm up time is greatly reduced and the house will remain warm all day and night.

When mixing standard radiators with cast iron we find that if the central heating thermostat is sited near a standard radiator the heating may close down before the cast iron radiators sited elsewhere have reached full temperature. The solution is to slow down the standard radiator influencing the thermostat by part closing the lockshield valve on that radiator (the usually covered end valve opposite the temperature control valve on the radiator used to balance the central heating system).

Heating a home is partly about heating the fabric of the building.  Cast iron radiators are again becoming popular amongst heating engineers and architects (particularly for older buildings) as they tend to retain the warmth in the fabric of the building which in turn  counteracts damp and condensation. 

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Q.

What should I paint my radiators with?

Most of our radiators are painted with cellulose or acrylic car spray paint, there is no need to use expensive specialist radiator paints - car paint is designed to cope with extremes of temperatures and be tough enough to withstand a great deal of abuse. Emulsion paint can be used, but the finish tends to not last very long cracking and peeling are common problems with using emulsion.

Powder coating produces a fabulous finish, BUT... the radiators are not designed to go through the prolonged baking process 9 times out of 10 all will be well, but especially on old cast iron radiators the paper seals between the sections can be damaged, replacing these is a very hard task. If you want to powder coat a radiator find a powder coater who uses a low temperature baking process.

A similar looking end result to powder coating can be achieved using products like "Plasti-coat" a spray paint available from DIY stores.

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Q.

Can you arrange delivery?

Yes. Generally delivery to mainland UK is £25 per order, however, there are limitations to this for remote areas with certain radiators. Areas affected are North of Perth, Mid and North Wales and South of Exeter - but this only applies to some of our radiators.

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Q.

How long does it take to get a radiator?

Stock items, generally whites, chromes and grey metallicas take 7-10 days, smaller radiators can be sent by courier which takes 4 working days from order. Cast iron radiators vary between 7-10 days in primer (Clasico, Liberty and Burlington), 3-5 weeks in a colour depending upon the style.

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Q.

What do radiator connections BBOE etc stand for?

BBOE - Bottom Bottom Opposite Ends (like most standard radiators)
TBOE - Top & Bottom Opposite ends (many old cast iron radiators were connected this way)
TBSE - Top & Bottom Same Ends (many old cast iron radiators were connected this way)

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Q.

Do you have a showroom where I can see the radiators?

Yes. We have a 1000 square feet showroom where we have examples of nearly all of our radiator ranges on display. The showroom has now been extended (March 2004) and we now have well over 100 radiators and heated towel rails on display. Click here for directions and opening times. 

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