Bathroom radiator now only works when the pump runs Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[JohnWB]

I have a CH system with a floor standing boiler, storage tank, a pump, diverting valve plus room & tank thermostats.

Up untill a week or so ago, the bathroom radiator (with a thermostatic valve), which is on the storage tank piping, was always nice & warm.

Since then the radiator only gets hot when the tank calls for heating & as soon as the tank thermostate clicks off then the radiator starts to cool & in a few minutes is cold.

I have checked the header tank which is full, bled the radiator which had no air in.

Now I am stuck as to what it could be, does anyone have any ideas as to what to do please.

[plastic_man77]

The rate at which the rad cools is of no importance, as if the rad gets up to the same temp as it normally does, it will only cool as quickly as it ever did. It's only the lengh of time the rad is heated that seems to be of concern.

Therefore, it sounds to me like someone has either changed your hot water settings (cylinder temp or clock parameters), or discovered an immersion heater was left on and has now turned it off or, you are mistaken about the pipework configuration- meaning the rad may actually be on the heating circuit and you are now using the heating differently, due to the improved weather conditions compared to a few weeks ago.

Your rad stat may be faulty, but it's rare. Try turning it up to max or removing the valve head so there's no control?

Also, think carefully- when you have touched the rad (while the hot water is calling), if it was cool, what did the room feel like? If the room temp felt ok, then the rad might have been cool because the rad stat had turned it off- therefore doing its job. Does the bathroom catch the sun?

I'm guessing your problem is only down to your system settings.

[JohnWB]

The rate at which the rad cools is of no importance, as if the rad gets up to the same temp as it normally does, it will only cool as quickly as it ever did. It's only the lengh of time the rad is heated that seems to be of concern.

Therefore, it sounds to me like someone has either changed your hot water settings (cylinder temp or clock parameters), or discovered an immersion heater was left on and has now turned it off or, you are mistaken about the pipework configuration- meaning the rad may actually be on the heating circuit and you are now using the heating differently, due to the improved weather conditions compared to a few weeks ago.

Nothing has changes in the system for years, The immersion is not used, cylinder stat is working ok at the normal 60deg, clock is as usual.

I checked the piping & it is piped across the H/W Tank & the weather has not changed much for weeks

Your rad stat may be faulty, but it's rare. Try turning it up to max or removing the valve head so there's no control?

I checked the Rad Stat & took the top off, no difference.

Also, think carefully- when you have touched the rad (while the hot water is calling), if it was cool, what did the room feel like? If the room temp felt ok, then the rad might have been cool because the rad stat had turned it off- therefore doing its job. Does the bathroom catch the sun?

When the tank stat calls for heat the radiator becomes very hot. The difference in room temp between now & before is as though the Rad was not there. The room has gone from being around 65 deg to down near 50 with the rad always cold except when the tank stat calls for heat

I'm guessing your problem is only down to your system settings.

[plastic_man77]

Your problem sounds a bit complicated and as nobody else has responded to your post, I think it's probably time you picked up the telephone and call a local heating engineer to it.