Different companies sometimes state different heat outputs for the same radiators, why?

Calculating your heat output requirement from a radiator and finding the appropriate size of radiator can be confusing. 

For example:

You provide your room measurements and your radiator specialist, Joe Bloggs Radiators, recommends that you need 1200 Watts heat output from your radiator.  Consequently they recommend a radiator that meets your requirements; X radiator in white, 600mm high x 1000mm wide, which gives out 1264 Watts. 

However, your plumber tells you that the same radiator, X radiator in white, 600mm high x 1000mm wide but from his supplier, ACME Radiators, only gives out 1000 Watts.  How can this be? 

The answer is probably that Joe Bloggs Radiators are advertising their heat outputs at the British standard whereas ACME Radiators are advertising their heat outputs using the newer European standard. 

To explain, heat outputs can be measured in 2 different ways; the way they are measured is done against the “delta T” or “Δt” of the system. 

In the UK, the standard for calculating heat outputs is illustrated by the following example:

• Flow water temperature (on entering the radiator) – assumed to be at 90˚C
• Return water temperature (on exiting the radiator) – assumed to be at 70˚C
• This means the average water temperature running through the system is assumed to be   80 ˚C
• From this figure, you minus the average room temperature – assumed to be 20 ˚C
• This equates to the Δt60 ˚C standard.

In Europe, the standard for calculating heat outputs is illustrated by the following example:

• Flow water temperature (on entering the radiator) – assumed to be at 75˚C
• Return water temperature (on exiting the radiator) – assumed to be at 65˚C
• This means the average water temperature running through the system is assumed to be   70 ˚C
• From this figure, you minus the average room temperature – assumed to be 20 ˚C
• This equates to the Δt50 ˚C standard.

To be clear, there is no difference in the radiator, it is just a different way of recording the performance and heat output.  Like metric versus imperial; the numbers may be different, but they mean the same thing. 

The reason that retailers still often use the original British Δt60 ˚C is because most domestic plumbers and heating engineers still calculate heat requirements to this standard.  Although most manufacturers now using the European standard of Δt50 ˚C.

The important thing is to compare like with like.  Check whether your heat output requirement has been calculated at the Δt60 ˚C or Δt50 ˚C standard then match the radiator output using the same standard.

It is easy to convert a Δt50 ˚C heat output to a Δt60 ˚C heat output and vice versa:

• To convert Δt50 ˚C to Δt60 ˚C, multiply Δt50 ˚C heat output by 1.264.
• To convert Δt60 ˚C to Δt50 ˚C, divide Δt60 ˚C heat output by 1.264.

So in conclusion, when buying a radiator, make sure you are comparing like with like; check the testing standards used and convert the figures as necessary or, to save yourself time and hassle, contact a reputable radiator expert who can do all this for you.

For more information on radiator heat outputs and expert advice on choosing a radiator with the appropriate heat output for your space then contact a radiator specialist such as Feature Radiators.  For face-to-face advice and to see over 250 display models then visit their showroom at The Old Post Office, 134-140 Main Street, Bingley, West Yorkshire, BD16 2HL, call them on 01274 567789 or browse their products at www.featureradiators.co.uk.

How warm should my house be?

How warm should my house be?

“How warm should my house be?” is a common question we encounter at Feature Radiators. An internet search will throw up numerous conflicting answers and opinions, so it’s easy to become confused.

The idea behind central heating is to maintain a comfortable temperature within each given room.  But some like it hot, others not.  One person’s “comfortable” room temperature may feel distinctly chilly or stiflingly hot to another. Which is what we find when we have ‘temperature wars’ here in the office at Feature Radiators. Why? - Because we’re all different, with different backgrounds, different metabolic rates, different attitudes and different lifestyles.  

Comfort is subjective.  Some of us choose to keep our homes warmer whilst others opt for a fresher feel with lower temperatures and additional layers of clothing. 

When deciding on the right temperature, you can’t please all the people all the time.  However, a key consideration, which is universally applicable when considering the optimum temperature for a room is “How is the room used?”

When generating heat calculations for the customers of Feature Radiators we like to consider the common sense observations below.

Rooms in which we wear little or no clothing, like bathrooms, need to be warmer.

Rooms where we lie under duvets and blankets don’t need to be as warm.

Rooms where we sit and relax and where we are not especially active, like dining rooms and sitting rooms, need to be warmer.

Common areas, like hallways and landings, which are used as walk-throughs, don’t need to be as warm.

Areas with appliances, such as fridges and ovens, and in which we move around a lot, like a working kitchen, need less heat.

Whilst there is no right or wrong answer, there are some guidelines within the heating industry.  The minimum suggested design temperatures for each type of room, as outlined in BS5449:1990, are listed below.   

 

Room type           Temp °C

 

Lounge /

Study /

Games Room - 21

Dining room   - 21

Kitchen          - 18

Kitchen / Dining Room - 21

Hallway / Landiing - 18

Cloakroom / Toilet / Utility Room - 18

Bedroom -18

Bathroom - 22

Dressing Room - 21

Storeroom - 16

To ensure a room can reach its desired heat, heat calculations are essential and installing the correctly sized radiators is imperative.

The best way of maintaining the desired heat once it has been reached is through the use of thermostatic valves which offer control of room temperature. The numbered dials each relate to a temperature, once this is sensed by the thermostatic head, the valve will restrict water flow. So knowing the specific dial numbers temperature is a must for heating specific rooms.

If you require further information regarding the optimum level of heating for more specific and vulnerable age groups such as the very young, elderly or infirm; the NHS and charities such as Age UK can offer advice.  

For more information on heating your rooms, contact Feature Radiators on 01274 567789, visit their large showroom in West Yorkshire or visit their website www.featureradiators.co.uk