Temporarily removing radiator and still using CH...

[SyTech]

Quick question which may have a really obvious answer: if I remove a radiator for decorating but don’t replace it immediately and want to put the central heating back on, do I need to connect the radiator back up first to ‘complete the loop’ or can I leave the 2 pipe ends (temporarily) capped off until such time as I’m actually ready to re-fit it?

 

[terryplumb]

Yes ,you can still use the central heating,but do cap the valves ( or pipes if the valves are removed). Unless you have a single pipe system ,all other rads should heat as normal.

 

[SyTech]

Thanks for the reply. Reason for asking is a few weeks ago I removed a radiator in a spare room to redecorate and ultimately re-position it a little further along the same wall. The painting has been done and the new radiator ordered but not arrived yet, so the existing connections are just sitting capped off. Last night my g/f tried to put the heating on for the first time in a while but all it did was fire up for about 15-20 seconds at most then switch itself off.

Hot water still works fine and there are no error lights or the like coming up on the boiler itself so trying to eliminate as many possible issues as I can before giving up/calling someone more qualified to come and take a look. Only thing that has physically changed since we last used it is the (temporary) removal of this radiator so wondered if it may be down to that...

 

[oldbutnotdead]

Is this a pressurised system? (Is there a pressure gauge on the boiler). If yes then have a look at it, you may have dropped pressure when you took the rad off. Or maybe the pump hasn't turned since March and has given up the ghost.....

 

[terryplumb]

Is it a combi boiler or other system ?

 

[SyTech]

It’s a combi system: Greenstar 28i boiler with a Drayton Digistat +rf wireless thermostat installed.

The batteries in the thermostat are fine and it appears to be sending a signal as the little green light on the receiver is on whenever the actual temperature is lower than what it’s set at.

On the boiler itself the blue light is constantly on and the hot water works fine too but whenever the heating tries to power up the burner indicator light comes on for about 20 seconds or so before switching off and everything going quiet again.

 

[Harry Bloomfield]

If you have TRV's, and the radiator you are taking out is not the one radiator installed without a TRV, then yes, you can run it without reinstalling that radiator. When TRV's are fitted, there is always one rad fitted without a TRV as a bypass, or a separate bypass is fitted. The boiler must always have some water circulation through it.

 

[SyTech]

Is this a pressurised system? (Is there a pressure gauge on the boiler). If yes then have a look at it, you may have dropped pressure when you took the rad off

Pressure has been sat steady at just over 1 since I took the radiator off and re-filled the system, topped it up to 1.5 this morning just in case but that made no difference. Usually when the CH first powers on the needle will 'dip' slightly then climb back up as the heating kicks in but as of yesterday's attempts to get it going it's not budging in the slightest.

Or maybe the pump hasn't turned since March and has given up the ghost.....

Based on initial google results this is my fear but as mentioned earlier would like to eliminate as many possibilities as I can before having to pay anyone to come out and (possibly) confirm bad news...

If you have TRV's, and the radiator you are taking out is not the one radiator installed without a TRV, then yes, you can run it without reinstalling that radiator. When TRV's are fitted, there is always one rad fitted without a TRV as a bypass, or a separate bypass is fitted. The boiler must always have some water circulation through it.

Definitely not the bypass radiator that we've taken off which is still connected in the downstairs hallway

 

[SyTech]

Having done another search on this forum have found an old thread which describes a near identical situation to what is happening with my boiler:

https://www.diynot.com/diy/threads/...nior-hot-water-but-no-central-heating.270680/

Suggests it may be an issue with the diverter valve?

 

[Harry Bloomfield]

Usually when the CH first powers on the needle will 'dip' slightly then climb back up as the heating kicks in but as of yesterday's attempts to get it going it's not budging in the slightest.

To my mind - That means the pump isn't running, possible seized or jammed. Can you get to it? In the end of the shaft will be a removable plug, a little water might leak out as that is removed. Behind which is the slotted end of the motor shaft. When their is a call for heating, the shaft should be spinning. Try turning it with a slotted screwdriver, it should be free to turn.

 

[ScottishGasMan]

Firstly, dont start taking the cover off the boiler to get to the pump, 1, its not your pump, 2, the case on those boilers acts as a seal between the room and the sealed chamber where the combustion components are.

Chances are it may well be the diverter valve thats gone, at this stage I would be calling in an installer to look at it, its not because of your radiator being off by the sounds of it.