Central Heating Radiators


·       This is a consumer information video, exclusively about Central Heating Radiators.

·       It will answer the 7 questions below to fully educate both domestic end users, and tradesman. 

·       Note: We have separate videos for electric radiators… and for dual radiators (which run on both central heating and electric), so ensure you are watching the correct video.

Questions Answered in this Video (including time markers for each):


[01:55] 1. How do I calculate the required output? 

  • Explains how to work out the heat output requirements for your cenral heating designer radiators.
  • Discussed how to use our heat requirement calculator.
  • Also discussed how you can use your existing radiators as a guide to working out your heat output.

[03:13] 2. What’s the difference between BTUs and Watts?

  • Gives a detailed overview of the difference between BTUs and Watts as a measurement of heat output for radiators.

[04:14] 3. What does Delta mean in relation to BTUs mean?

  • Explains the difference between the different Delta outputs used in relation to heat output - Delta T50, Delta T60 and Delta T70.
  • Discusses the laboratory condition for testing heat outputs which comply with EN442 regulations.

[06:41] 4. How does the style of a radiator affect its heat output?

  • Compoares the different broad styles of radiators we offer and how the different styles directly affect the heat output.

[09:24] 5. What options do I have in positioning my radiator valves?

  • Explains the different options for locating your radiator valves on your radiator - side or underside entry.
  • Gives you the knowledge and understanding to influence the final look and enable you to discuss these with your plumber.

[10:54] 6. Whare is the best place to install my Radiator?

  • Advises the best place to physically located your radiators in your room - under a window on an external wall.

[11:25] 7. What should I know about the installation process?

  • Discusses some of the common issues customers face have after having inexprienced plumbers installing our radiataors for them.
  • Explains the process of 'balancing the system' to ensure none of the radiators are colder than the rest in the system.
  • Explains how radiator diverters (or radiator baffles) work to aid internal water flow ensuring all areas of the radiator get hot.

After watching this video you will know all you need to know, to make an informed decision about purchasing an designer radiators for your central heating system.

We hope you find this, as part of our series of technical videos, helpful and thank you for watching.


Chart for Using Your Existing Panel Radiators as a Guide to Your Required Heat Output:

When your house was built, the contractor or builder will have spent time choosing the right radiators taking into account how the house was built. We often find people seeking to replace their standard panel radiators with designer radiators, so taking the output of the existing models (if you are happy with that heat) makes perfect sense.

Measure the height and width of your existing radiator, then use the table below to find the type you have and determine its power output in BTUs. Remember if your existing radiators aren't warming your room efficiently, increase the heat output from the figures given below, for the replacement model you choose.

Single Panel
Single Panel

Length   600mm 900mm 1200mm 1500mm 1800mm
    2ft 3ft 4ft 5ft 6ft
Height 300mm (12ins) 1121 BTUs (t60) 1681 BTUs (t60) 2241 BTUs (t60) 2802 BTUs (t60) 3362 BTUs (t60)
  450mm (18ins) 1638 BTUs (t60) 2457 BTUs (t60) 3276 BTUs (t60) 4095 BTUs (t60) 4914 BTUs (t60)
  600mm (24ins) 2112 BTUs (t60) 3168 BTUs (t60) 4224 BTUs (t60) 4849 BTUs (t60) 6336 BTUs (t60)
  750mm (30ins) 2500 BTUs (t60) 3748 BTUs (t60) 5000 BTUs (t60) 6250 BTUs (t60) 7440 BTUs (t60)


Single Panel With Fins
Single Panel With Fins

Length   600mm 900mm 1200mm 1500mm 1800mm
    2ft 3ft 4ft 5ft 6ft
Height 300mm (12ins) 1595 BTUs (t60) 2392 BTUs (t60) 3190 BTUs (t60) 3987 BTUs (t60) 4784 BTUs (t60)
  450mm (18ins) 2414 BTUs (t60) 3621 BTUs (t60) 4827 BTUs (t60) 6034 BTUs (t60) 7241 BTUs (t60)
  600mm (24ins) 3103 BTUs (t60) 4655 BTUs (t60) 6207 BTUs (t60) 7758 BTUs (t60) 9310 BTUs (t60)
  750mm (30ins) 3707 BTUs (t60) 5560 BTUs (t60) 7414 BTUs (t60) 9267 BTUs (t60) 11120 BTUs (t60)


Double Panel
Double Panel

Length   600mm 900mm 1200mm 1500mm 1800mm
    2ft 3ft 4ft 5ft 6ft
Height 300mm (12ins) 1724 BTUs (t60) 2566 BTUs (t60) 3421 BTUs (t60) 4310 BTUs (t60) 5172 BTUs (t60)
  450mm (18ins) 2414 BTUs (t60) 3621 BTUs (t60) 3742 BTUs (t60) 6034 BTUs (t60) 7241 BTUs (t60)
  600mm (24ins) 3017 BTUs (t60) 4526 BTUs (t60) 5987 BTUs (t60) 7543 BTUs (t60) 9052 BTUs (t60)
  750mm (30ins) 3381 BTUs (t60) 5560 BTUs (t60) 7414 BTUs (t60) 9267 BTUs (t60) 11120 BTUs (t60)


Double Panel With Single Fin
Double Panel With Fins

Length   600mm 900mm 1200mm 1500mm 1800mm
    2ft 3ft 4ft 5ft 6ft
Height 300mm (12ins) 2500 BTUs (t60) 3750 BTUs (t60) 5000 BTUs (t60) 6250 BTUs (t60) 7500 BTUs (t60)
  450mm (18ins) 3707 BTUs (t60) 5560 BTUs (t60) 7414 BTUs (t60) 9267 BTUs (t60) 11120 BTUs (t60)
  600mm (24ins) 4741 BTUs (t60) 7112 BTUs (t60) 9483 BTUs (t60) 11853 BTUs (t60) 14223 BTUs (t60)
  750mm (30ins) 5517 BTUs (t60) 8276 BTUs (t60) 11034 BTUs (t60) 13793 BTUs (t60) 16551 BTUs (t60)


Double Panel With Double Fins
Double Panel With Double Fins

Length   600mm 900mm 1200mm 1500mm 1800mm
    2ft 3ft 4ft 5ft 6ft
Height 300mm (12ins) 3275 BTUs (t60) 4914 BTUs (t60) 6552 BTUs (t60) 8189 BTUs (t60) 9827 BTUs (t60)
  450mm (18ins) 4483 BTUs (t60) 6724 BTUs (t60) 8965 BTUs (t60) 11207 BTUs (t60) 13448 BTUs (t60)
  600mm (24ins) 5776 BTUs (t60) 8664 BTUs (t60) 11551 BTUs (t60) 14439 BTUs (t60) 17327 BTUs (t60)
  750mm (30ins) 6896 BTUs (t60) 10345 BTUs (t60) 13793 BTUs (t60) 17200 BTUs (t60) 20689 BTUs (t60)


Converting Watts to BTUS (and vice versa)?

BTUS = Watts multiplied by 3.41,  WATTS = BTUS divided by 3.41


 Converting Heat Output between different Deltas?

Be mindful when comparing radiators across different suppliers to check the Delta given on the heat outputs, as this can falsify the heat outputs when comparing like for like products which have been given with different Delta heat outputs.
If it isn't specified (like it is on all of our products) you should ask the other supplier what Delta figure is used.

If you wish to convert our Delta T60 ratings, to give you a true indication as to heat output when comparing with other suppliers in different formats, use these formulas:

·         T70 = T60 multiplied by 1.33         T70 = T50 multiplied by  1.4

 ·         T50 = T60 divided by  1.264          T50 = T70 divided by  1.4

 ·         T60 = T50 multiplied by  1.264          T60 = T70 divided by  1.33

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