Geyser list all heat output figures as Delta T60, which is a formula determining the difference between the room temperature and the internal temperature of the radiator at the time when the heat output was tested. There are three different ways to specify heat output Delta T50, Delta T60 and Delta T70. Most British plumbers will specify heat output in Delta T60, which is why here at Geyser we give all heat outputs in T60, so it corresponds with the plumbers specifications. The European standard is Delta T50, which will give a slightly lower heat output than T60. 

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 multplied by 1.33         T70 = T50 multplied by  1.4

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

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

To explain the concept of Delta in more details; All heat outputs have been obtained from controlled laboratory tests, using a standard installation criteria. From 1st July 1997 all radiators manufactured in Europe need to conform to the European standard BS EN442. Under this standard it is necessary to test radiators with a flow (inward) water temperature of 75 C and a return (outward) temperature of 65 C, in a test room with a consistent air temperature of 20 C. At a 75 C flow water temperature, and a 65 C return water temperature the mean average water temperature (MWT) is 70C. If we minus the room temperature of 20 C, we are left with a temperature differential of 50 C or a Delta T of 50.

Tips and Advice:

• A: Ask your plumber to tell to confirm what delta calculation he is using to specifiy the BTU figure they have given you. Delta T50, T60 or T70. Use the guide above to convert if required.  
• B: Look at the heat outputs given by other radiator suppliers, as this will 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.

7. Will a Heated Towel give out as much heat as a Radiator?

The simple answer to this question is yes, if the heated towel rail has the same BTUs as the radiator. Typically however, size for size a heated towel rail will give out less heat output than a radiator due to it's design, as it is made up of rungs or bars with gaps for towels. If you plan to have a heated towel rail as the main source of heat for your bathroom try and go for the largest rail you can fit - our largest rails are up to 1760mm high. Follow This Link to view all the heated towel rails we sell on one page, ordered by heat output, with the hottest ones at the top. These are over 3500 BTUs high for some of the stainless steel heated towel rails, which is just as good as any radiator. If you can only fit a smaller rail in your bathroom, then consider a Towel Ring for Heated Towel Rails, as this will stop the towels from cosuming the full heat output and leave the bars exposed to take the chill off the air in the room.

8. How do Geyser calculate the heat outputs for your Electric Towel Rails?

The heat outputs listed on all of our electric heated towel rails and electric radiators are determined by the wattage of the element, supplied with it. Ie If it is a 400w element.. we list the heat output as 400watts and 1364 BTUS (watts x 3.41). This is why you may see the same size rail with the same heat output listed. For Example: If you had two electric towel rails, say 1150x350 and 1150x450, but both are supplied with a 400watt element, so in reality the heat output of the 1150x450 rail is going to be higher, as it has a greater surface area. However, we simply choose to list our heat outputs based on the output of the element (as it is the element heating the solution and thus ultimately heating the room).

9. How do Geyser decide the wattage of element supplied with the Electric Heated Towel Rails?

The element supplied is calculated based on the longest dimension of the heated towel rail (so typically the height measurement, but if it is wider than it is tall, we use the width measurement). Below is a list of all the different size elements we supply with our electric towel rails and the corresponding sizes of electric towel rails, those elements are supplied with:

Single Heat Elements (all available in chrome & 150,400,900 in white)

150 watts:   0mm high   >   700mm high

200 watts:  700mm high   >   900mm hgh

400 watts: 900mm high   >   1200mm high

600 watts: 1200mm high  >   1500mm high

900 watts:  1500mm high   >   1800mm high

Variable Heat Elements (all available in chrome & matt grey)

300 watts: 0mm high  >   900mm high

600 watts: 900mm high   >   1500mm high

1000 watts:  1500mm high   >   1800mm high