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Delta T50? Delta T30? Watts vs BTUs? We are here to help....

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What is the difference between Delta T300C, Delta T500C and Delta T600C in relation to heat outputs?

In a nutshell, Delta T300C is most applicable for an Air Source Heat Pump (ASHP), Delta T500C is most applicable for a domestic oil or gas boiler, and Delta T600C is more suitable for a commercial heating system with higher flow temperatures.

 

It is very important you use the correct Delta T figure when sizing and selecting your radiators, as the actual heat output the radiator will produce can vary drastically depending on the type of heat source you are using on your heating system. For example, a radiator running at Delta T300C would give out roughly half the heat output of a radiator running at Delta T500C.

 

Similarly, some retailers will even advertise their radiators at Delta T700C, which means you would need to supply the radiator with 950C water (near boiling point) to achieve the heat outputs they are claiming. This is simply not possible on most domestic heating systems and means your radiator will be drastically undersized, as most boilers operate at a flow temperature of around 70 to 750C.

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An Air Source Heat Pump is typically sized at Delta T300C which is based on a flow temperature of 550C, a return temperature of 450C and a room temperature of 200C. However, this depends on your particular system design as some systems are designed around even lower operating temperatures such as a 450C flow and 400C return (Delta T22.50C).

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An oil or gas boiler is typically sized at Delta T500C which is based on a flow temperature of 750C, a return temperature of 650C and a room temperature of 200C. Again, this depends on your particular system as more modern condensing boilers often operate at a slightly lower temperature than this for maximum efficiency.

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If you are in any doubt which figure you should be looking at, please contact us to discuss your particular system and we will be happy to help you size the radiators correctly.

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How do I convert Watts to BTUs?

Simple…. Watts x 3.412 = BTUs

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How do I convert BTUs to Watts?

Simple…. BTUs ÷ 3.412 = Watts

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How do I calculate how much heat my room requires?

We have included a Heat Loss Calculator on our website to assist you with calculating the heat requirement for your room. Please fill the necessary information into our calculator, and it will provide you with an approximate heat requirement for you room, in both Watts and BTUs. Then simply choose a radiator that gives you the required amount of heat.

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Are The Radiator Shop radiators & towel rails compatible with my system?

The Radiator Shop radiators & towel rails are compatible with normal central heating systems and have British Standard fittings (BSP).

On an existing system, you can replace all the radiators or just the ones you want.

The Radiator Shop radiators work with all types of boiler, and with all types of circuit including sealed systems, combination boiler systems and condensing, closed-circuit systems with an expansion tank. (If you have an expansion tank, the top of the highest radiator must be at least 60 cm two feet below it.)

Note that ALL The Radiator Shop radiators must be placed on the central heating system and never on the hot water system that feeds the taps i.e. a Direct system (which is separate). The water flowing to taps is constantly refreshed and its high oxygen content will rapidly corrode any radiator. Only stainless steel or solid Brass products can be used with Direct systems.

 

How do I order my new radiator?

We are able to assist you and process your order in many ways. Most customers prefer to visit our showroom in Newtownards to see our vast range of display models and talk about their specific requirements in detail. We can of course also offer assistance and process your order over the telephone, via email or online.

 

How long will I have to wait for my new radiator?

We hold some of our most popular lines in stock and these are available for immediate delivery either through our showroom or online. Most other radiators that are finished in white are held in stock with our suppliers in England so delivery is usually only 5 to 7 working days. If the radiator is in any other colour, or a non stock or bespoke size, the delivery is typically between 4 to 6 weeks. Please note that during the months of July & August the delivery time of non stock or bespoke painted radiators is likely to be extended to around 8 to 10 weeks due to factory summer closures in Europe. If you require your radiator within a certain time frame, we suggest you contact us for a current delivery estimate.

 

Does the price of the radiator include for valves?

No, our radiators do not come with valves, these have to be ordered separately if they are required. This is due to the fact that we have a vast range of valve designs, control options and colours available to compliment our radiators and to match existing fittings (e.g light switches, taps etc). Valves are typically available in either Thermostatic or Manual options, and in a range of finishes including White, Chrome, Brushed Nickel, Black Nickel, Antique Brass etc. We also have a range of matching pipe covers available. Please visit our Valves & Accessories section for more details.

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I have exact pipe centres that I need to match, do you have a radiator suitable?

Thanks to our huge range of radiators and towel rails, some of which are made to measure, we are sure to have something suitable to match your existing pipe centres. We pride ourselves on going the extra mile for our customers so please get in touch and tell us the dimensions you are trying to match and we will go through our extensive range of products to find you a solution.

 

I have a very low window sill, but I still want to place my radiator underneath it, what are my options?

We have been asked this question many times, which is why we have put together a collection of radiators for just this instance. We have a range of double panel convector radiators that are only 200mm high and come in a number of lengths from 800mm to 3000mm long. These would match perfectly with your existing double panel radiators. We also have a range of flat panel radiators that come in heights from 70mm to 350mm. These can be made any length from 400mm, right up to 6000mm long!! Both of these ranges can either be wall mounted or placed on feet.

 

What clearances do I need above and below my radiator to ensure maximum efficiency?

We recommend that minimum clearances of 50mm above and 100mm below should be left clear so heat from the radiator can be effectively distributed.

 

I have a very narrow wall available but I need a high heat output, what are my options?

The Volcano Vertical radiator has one of the highest heat outputs for its size, enabling it to fit into narrow spaces and on pillars. It is available in a round or square tube version, and a range of over 190 colours to compliment your interior. They can also be ordered with underneath valve connections meaning that the valves do not protrude out either side of the radiator, thus further reducing the amount of wall space that is required. Also check out our Tilbrook and Sofi radiators which have underneath valve connections as standard.

Trouble Shooting

 

My new Cast Iron radiator has been delivered in two pieces, why is this?

Due to the weight of Cast Iron radiators, it is sometimes necessary to deliver the larger radiators in two or more pieces. However, joining couplers and a joining key are provided to enable the plumber to join the radiator together. A copy of our Cast Iron assembly instructions are also provided along with the radiator. 

 

My radiator is hot at the bottom but cold at the top?

This is normally caused by trapped air inside the radiator. Turn off the heating system (not the radiator valves) and allow the system to cool. Then, if there is a Manual air vent fitted, use a radiator key/flat screwdriver to loosen the centre screw of the air vent and you should begin to hear air escaping from the small hole in the air vent. Once the air stops and is replaced by water coming out through the small hole, tighten up the centre screw again. Turn the heating system back on and your radiator should now be heating evenly. (Caution: it is wise to use an old rag to catch any squirts of water from the air vent to avoid staining walls etc.)

If you have an Automatic air vent fitted to your radiator, these gradually vent air from your radiator over time so it is unlikely that you will have any air inside the radiator after 72 hours of installation. In some remote cases, there may not be quite enough pressure in your system to allow the Automatic air vent to function fully, so we would suggest fitting a Manual air vent to the radiator as well to allow the option for manually venting as above.

 

My radiator is heating unevenly or has hot and cold patches?

This is normally what is known as a “balancing” issue and means that there is not enough hot water getting to the radiator to allow it to heat up fully. The radiators that are last on the line or furthest from the boiler are the most susceptible to this issue. The solution is a simple one but can take time to resolve. It involves working out which of your radiators is nearest to the boiler and closing down this radiators return valve slightly with an allen key or screwdriver, but still open enough to let the radiator heat up fully. This forces more hot water along to the next radiator, where you will have to repeat this process again, and so on, until you gradually start to feel the heat evening out on the radiator that was not heating fully. If you are unsure about doing this, a plumber should be contacted.

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