Temperature on boiler

[ma701ss]

Hi,

I read somewhere today that the temperature on the front of the boiler, which I thought was just the temperature for the water supplied to the rads, is actually the temperature of the water that is supplied to the coil in the cylinder. Therefore, apparently if the cylinder thermostat is set to 60 degrees but the boiler temperature is set to 50 degrees, then the cylinder will never reach 60 degrees and so the boiler will always be on trying to heat the cylinder to 60 degrees but of course will never get there. This was from a CH engineer I believe but is this correct?

ma701ss

 

[Puddle]

Hi,

I read somewhere today that the temperature on the front of the boiler, which I thought was just the temperature for the water supplied to the rads, is actually the temperature of the water that is supplied to the coil in the cylinder. Therefore, apparently if the cylinder thermostat is set to 60 degrees but the boiler temperature is set to 50 degrees, then the cylinder will never reach 60 degrees and so the boiler will always be on trying to heat the cylinder to 60 degrees but of course will never get there. This was from a CH engineer I believe but is this correct?

ma701ss

Well yes,as you say the water in the boiler heats rads and cylinder coil so you can not heat anything hotter than the boiler temp is set
The cylinder thermostat will not turn power off to boiler until the 60 deg is reached,so with 50 deg on boiler this does mean never,however the boiler will turn off when it reaches 50 deg so will not be on all the time,will just come on after pipework heat loss if no hot water used

 

[ma701ss]

thanks but not clear on what you mean by the boiler reaching 50 degress. I thought the boiler set to 50 degrees means that the boiler just heats the water passing through it to 50 degrees, so will continue to supply water at 50 degrees until there is no demand for it. So if the cylinder is set to 60 degrees, I thought that the water will be endlessly supplied through the coil at 50 degrees. Why also does the thermostat dial have a radiatior symbol on it if it also heats water for the boiler?

 

[migoplumber]

just means that the valve to the cylinder will always be open, calling for heat.
if your boiler flow temp is less than that, as you stated the cylinder will never reach the temp your asking for.

 

[Puddle]

what make,model boiler is it ?

 

[ma701ss]

The thing with my boiler is that the temp on the boiler fluctuates without even touching it. Sometimes it says 54 then the next 62.

Its a British gas 330. Think it's a gloworm.

 

[Puddle]

The thing with my boiler is that the temp on the boiler fluctuates without even touching it. Sometimes it says 54 then the next 62.

So you have not set the boiler to 50 deg,it is probably higher,you just see it there sometimes and sometimes 62 deg,the temp you are looking at is the temp of the water at that time and will fluctuate as water is heated