Heating downstairs not working consistently. Upstairs working ok.

[Domtvr]

Probably asked many times (complete novice) but having issues with ch. The full system was put in 4 years ago and has been working fine since then. Hot water working fine and actuator thingy is switching fine as well. It appears when system is fully cold and starts we get heating upstairs and downstairs but after a while we loose heating downstairs. Upstairs seems fine. The pump still seems to be working albeit a couple of times it's started to whine very loudly. I've also heard when the pump turns off a gush of water down the pipes downstairs. I've been bleeding radiators and there seems to be air in most of them every time I do it. I've checked tank in attic and there's water in it (seems to be a lot of sediment in it though).

Finally got my plumber into check it and replaced pump and when he left heating was on across all radiators. 4 hours later downstairs not working again. Checked the pipe that comes back from downstairs and its only luke warm

One final thing the boiler does seem to get up to temp and switch off a lot (not sure if that is relevant)

Any thoughts from the experts out there?

 

[AWheating]

could well be a circulation problem caused by air or sludge?

if you turn off all the upstairs rads do the downstairs stay on and keep warm?

 

[Domtvr]

Thanks for quick response. I'll try that in the morning (kids in bed now) if downstairs works I take it that means circulation problem?

 

[Domtvr]

Downstairs ch has been on all day with no problems. Any ideas what the issue could be?

 

[Domtvr]

Brand new pump.

 

[Derek Hardman]

Bleed the radiators with the pump off, it could be drawing air in, if downstairs work when upstairs are off I would think weak pump, partial blockage on manifold (probably microbore pipework), or just plain old balancing required, (has someone been messing with the valves?)

 

[Domtvr]

Wife did turn bathroom towel rail off to paint behind it just before problems started. I've bled radiators with pump turned off some radiators bled fine some bled but then stopped b4 any water came out. Pipework is normal 15mm. Just find it confusing as ch works around house for a couple of hours then just stops downstairs.

 

[Derek Hardman]

It sounds like a blockage to me, best to have the pipework temperature tested, see where the heat actually stops or reduces.

 

[Rickster123]

Sounds like a balancing issue to me. When you reconnected the towel rail did you just open the valves fully?

 

[aplombier]

Another vote from me for balancing as well. Can't be blockage as it works with upstairs off. Best way fully open downstairs valves and only give half a turn to upstairs valves and then fine tune as neccessary

 

[Domtvr]

The valve in bathroom was opened fully after it had been turned off. Our radiators upstairs are always set lower than downstairs ( about 2 on the tir's) downstairs normally fully open.

Still don't understand how heating works for a couple of hours upstairs and downstairs then stops downstairs but still works upstairs (tir's still set to 2 or 3 upstairs, not changed them for bout a year).

Ill try balancing them tomorrow. Thanks all of you for your help!

 

[aplombier]

It's not the thermostatic valves that need doing, its the lock shields on the other end. They will slow the flow to upstairs if only open half turn and force the water to downstairs.

 

[Domtvr]

My plumber came back today to check if pump was working. After investigation it was found that the down pipe from the filler tank had sediment and was casing a blockage he also took a t shaped thing out that apparently should let air out if there was any in system. Anyways all working now (albeit still had to pay for a new pump!). Thanks for all your advice.

 

[bewsh]

I would have said blockage in the cold feed if you were bleeding and no water/air was coming out.

Glad you found the issue and it's resolved!