Only one radiator is heating up? Whats going on?

theoallen

Hi there,

Sorry if I have posted this in the wrong place!

I'm having an issue with my heating and I can't seem to figure out what is happening. I recently moved into a new house (3 months ago), and up until yesterday I have had no problems with the heating. However, yesterday, all of a sudden, I realised that when the heating is on, it only appears to be heating up one radiator fully (the first in the system) and slightly heats the second radiator in the system. All of the others stay completely cold.

I have tried resetting the boiler, tried bleeding the radiators, tried balancing the radiators, and still, only that one radiator heats up. Does anyone have any idea why this could be? And how I can fix it? It's driving me crazy!

Thanks

footyguy

Sounds like it's time to get an expert in.

If it's been working perfectly for 3 months, and yesterday wasn't, and you had not touched anything, then sounds like something has gone wrong.

An incompetent person fiddling now could cause more problems and/or disguise the original fault.

viciovbuk

I had a similar problem and it was the valve next to the hot water cylinder that was stuck on "water" even if I turned on just the heating and switch off water. Is the radiator that becomes hot near the water cylinder?

System

Has the single radiator got a TRV fitted or is it being used as a system bypass? I agree with @viciovbuk that this sounds like a valve issue but without knowing more about the configuration of your system you are unlikely to get any useful/helpful advice

JJ_Egan

Sounds like a pump to me .

theoallen

So I've done some troubleshooting and this is what I've learnt:
When I reset the boiler, the boiler turns on for 25 seconds before turning on. The LED then flashes green, which according tor the manual, means that the 'Temperature has been satisfied". So I guess something is telling it that it is reaching the correct temp? However the house is only at 15c, so its definitely not the right temp!

So I'm now not sure if this is a boiler problem, or a thermostat problem?

System

theoallen wrote: »

So I've done some troubleshooting and this is what I've learnt:
When I reset the boiler, the boiler turns on for 25 seconds before turning on. The LED then flashes green, which according tor the manual, means that the 'Temperature has been satisfied". So I guess something is telling it that it is reaching the correct temp? However the house is only at 15c, so its definitely not the right temp!

So I'm now not sure if this is a boiler problem, or a thermostat problem?

Think of your system in two parts: one, heating and, two, hot water. Are you getting hot water? If your boiler is a combi boiler, then the boiler will usually fire whenever there is a hot water demand.

The clever bit is how the boiler circulates heat to the two parts. On a combi boiler it is either hot water or heating with the boiler flow travelling through a diverter valve - a bit like points on a railway. If you have a system boiler that heats a hot water cylinder, then the flow is usually controlled by two motorised zone valves. One, valve, the hot water valve, is controlled by your timer and a cylinder thermostat and the second, the central heating valve, is controlled by your timer and room thermostat. It sounds like one of your valves (or your only valve) is stuck or the motor has failed.

The fact that your boiler is cycling may indicate that there is a heating demand but there is no where for the flow to go because of the stuck valve. In some heating configurations, one radiator is left fully open as a pump over-run which is why this one radiator may be getting hot when the others are stone cold.

As the above is complete guesswork, you need to get a GSR engineer to look at your heating system.

House_Martin

theoallen wrote: »

Hi there,

Sorry if I have posted this in the wrong place!

I'm having an issue with my heating and I can't seem to figure out what is happening. I recently moved into a new house (3 months ago), and up until yesterday I have had no problems with the heating. However, yesterday, all of a sudden, I realised that when the heating is on, it only appears to be heating up one radiator fully (the first in the system) and slightly heats the second radiator in the system. All of the others stay completely cold.

I have tried resetting the boiler, tried bleeding the radiators, tried balancing the radiators, and still, only that one radiator heats up. Does anyone have any idea why this could be? And how I can fix it? It's driving me crazy!

Thanks

I ve had the same problem with a couple of rads.
turned out to be a sticking TRV valve on left hand side.set it full on, unscrew from below and with the help of a bit releasing oil slightly waggle the pin..but be gentle, dont hit it with a hammer !.Youtube has a good vid to show how to do this
The pin can stick. Just a slight waggle with a pair of pliers got both my rads working instantly after trying the other methods. The lockshield valves on the other side can also stick a bit.I ve found a bit of gentle tapping underneath the valve frees it.
If that does nt work , time to call in the plumber

theoallen

Right, that makes sense! We have a conventional boiler so the stuck valve could very well be the problem, Ill get in touch with an engineer to see if they can come out tomorrow!

Thanks

House_Martin

with the TRV valves it easy to unscrew the threaded ring by hand to lift off the thermostat part of it which reveals the pin underneath it .no water can leak out. Its this pin which can stick .Check the UK youtube videos for instructions

viciovbuk

If you see a switch on the valve you can try this: turn heating, water and the pump off, manually put the valve switch to heating and turn on just the pump and the heating and see if you can have your heating back for now