Not money saving but I have a problem with my heating

gibbyni

I have started using my heating again and for some reason my heaters are not heating up.

It’s an oil boiler and when I turn it on it fires up and heats for 5 min then switches off for a while and keeps going through this cycle.

I have bleed the radiators starting from closest downstairs and ended with upstairs. The downstairs were all fine, a few upstairs took about 10 sec to get all the air out.

Now I have 2 radiators upstairs that get a little warm but the others stay stone cold I have about 13 in total.

I did the bleed again and there was no more trapped air

Anyone any ideas what else to try before I have to get someone in ?

Silent_Dancer

Try

- Checking radiator thermostatic valves.
- the house thermostat
- the temperature the boiler heating is set to

Turn all to max and see if boiler cycles like you describe again. if it does its likely to be a boiler fault probably the control stat.

matelodave

Is the pump running - it sounds like you've just got convection current warming some of the rads and the boiler is short cycling because the heat isn't being taken away.

The other possibility is a stuck diverter valve

gibbyni

Ok so far
- Checking radiator thermostatic valves - Dont have, all there is is the old twist on off valves
- the house thermostat - Set well up to make sure its kicking in
- the temperature the boiler heating is set to - its at 75 but will crank it up to 90 later

I also tested it with the hot water this morning and its going through the same cycles there was plenty of hot water after an hour.

matelodave - the boiler sounds normal and is operating as it used to when the heating was working properly, its just that it looks to be heating less, as if I only had one or to radiators on.

matelodave

It appears that water isn't circulating around your heating system but is managing to heat the hot water tank which means that theres's probably not a lot wrong with the boiler.

Without knowing how your controls are configured it's hard to properly fault find by guesswork however it's likely that you've either got a diverter valve thats controlled by the room thermostat which is stuck and not allowing water to circulate around the heating circuit or that the pump might be controlled by the room stat and if it's not running will allow the boiler to heat up but not circulate the water - this would cause the boiler to short cycle as the water temp will be controlled by the boiler stat.
It's a common problem that the circulating pump can seize during the summer months if it is controlled by the room stat and not run occasionally.

The fact that it's a couple of upstairs rads that are getting slightly warm confirms that there is some slight convection circulation but the pump is not pushing water around the heating circuit