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Every winter we seem to play the same game.
We had a new boiler fitted about 4 years ago, and it's serviced every year.
The heating all around the house seems to work fine when the temperature outside is mild, but as soon as we get to low single figures or below, only the bathroom towel rail and 2 other rads will get hot.
We've had about 3 differing plumbers look at the issue but invariably this happens when the outside temp has warmed and all the heating is working again.
The boiler company sent their own engineer last winter after plumber 3 insisted it was a boiler issue, but now we're into this season's freeze, the same old issue is back.
Granted, I've not personally balanced the rads, but I've not the time or knowledge to do so.
None of the 3 plumbers have recommended this though.
Is there any hope out there for a warm house....and wife?!
Are you sure they were plumbers and not bike mechanics?
(psssst...wrong forum mate)
Did you bleed from the bottom or the top?
Did you use DOT4 or mineral oil?
Pipes freezing?
Airlock?
Where is the boiler? Upstairs?
Where are the rads that work and the ones that don’t?
From the top...
Forum fail
Mineral, always
No idea
Downstairs rads are not warming much. Upstairs are fine.
Oh, and boiler is upstairs too.
Suggests the boiler is not powerful enough for the amount of rads you have to me. Try turning off some that work and seeing if the ones that don’t then do.
We have a couple of radiators that weren't hot enough in winter, furthest from the boiler, turned out the TRVs don't seem to open enough, even on the highest setting, and despite being replaced. Unscrewed the TRV head (held in place by a lock ring) and boom, hot radiator.
Could be balancing, but you say they all work fine when the weather is warmer?
Or is it that some are shut or partially shut by TRV valves?
It could be undersized boiler, radiators or pipework, or even pump.
Or a combination of them.
It could be debris in the system.
You need to know what flow temperature the boiler is producing, and also the return.
There could be a bypass valve somewhere incorrectly set, or even worse a manual bypass that is fully open.
Lots more info needed to give and probably a site visit by someone who will take time to inspect the whole system and probably take some measurements to check heat losses, radiator outputs, temperatures etc.
I’m not surprised nobody has tried to balance the system as most seem incapable of understanding the concept, I’ve some notes which I can mail you on balancing that has helped a few here I think. timATj-twren.eclipse.co.uk
If at certain times all the rads heat up then there might not be a blockage. I reckon you need to balance the system properly first, it’s not very difficult, a cheap pipe thermostat and a screwdriver is all you need. It might be that when it’s cold the upstairs rads being closest to the boiler are using up all the heat before it gets downstairs. I had this issue with a new rad I put in downstairs, balanced it all and it was fine.
Is the boiler on all the time in the cold weather, or is it still cycling on and off? (or modulating down, anyway).
If so,
.I reckon you need to balance the system properly first
- Likely that the rads nearest the boiler are taking more flow than they can lose heat from, so hot water is just circulating back to the boiler which thinks its job is done and turns itself down/off.
Measuring the temperature of the inlet and outlet pipes from the radiators will tell you if this is the case straight away.
The boiler is on/off, not powering all the time, so it obviously thinks it's job is done.
Plenty of heat around the house today while it's 6 or 7 degrees outside.
Thanks for all the answers. The obvious next step, as I've already acknowledged, will be balancing.
[deleted - someone's already suggested it]
IANABE
but I would look at the pump speed setting , if its variable
Lever on side of pump with 1 11 111 on it. If its on #1 then try it on #3.
You will need to pop off the cover to do this . You wont die .
If the boiler is flaming out , and the downstairs rads are cold this suggests bypass valve . Could be something as simple as lowering the flow to the upstairs rads to increase flow elsewhere.
This is going to be the most idiotic questin ever , but have you tried setting the upstairs TRV's to frost and the downstairs to furnace? Fire it up and see what gives . Is there a towel rail on open loop? wind that off as well .
Is there a magnetic trap installed?
Was it powerflushed when commisioned?
Have you tested / checked your inhibitor ( nails in jar.- lid on )
We lost 2 of the downstairs radiators after the system got drained due to a leak. Couldn't get them to heat up, but remembered turning off all the upstairs radiators when this happened some years earlier. It worked. Then turned on the upstairs rads and ensured they were bled - we have one radiator that seems to be the point where air gets, so only ever need to bleed that rad.