Central Heating NOT

[Strangelite]

Last week the CH system stoped working

I've de-gunked the system [ it needed doing], flushed it and refilled.

all radiators have been blead.

the pump is <12 months old - and makes the right sort of noises - it's bleed vavle has been shown to be free of air.

when the CH is on the pipes round the pump get hot but nothing seems to reach the radiators.

any clues on how to fix this?

do I have a air lock somewhere ? if so how do I go about removing it
or do I have some other problem ?

All suggestions gladly received

 

[kevplumb]

what boiler/system etc

 

[Strangelite]

Boiler is a Baxi Solo 2 40 RS
CH System is not Sealed - head tank style.

TIA

 

[kevplumb]

1 check the pump is running and bled
unde the large screw let the air out put a small screwdriver in the hole and see if the shaft is turning
if you have a three port valve lock the lever on man and there should be a bleed point somewhere near it

 

[Strangelite]

Pump was operating,
and oozing water - no air in that part of the system.

I have switched all radiators off [apart from the nearest one] to see if that helped - nothing seemed to change

 

[fitz1]

3 or 2 port valve (check operation)

 

[Tony6]

Have you check the lock sheild if fitted on the first rad is open and the termostat is set correctly.

 

[Strangelite]

don't know what you mean about a 2 or 3 port valve

there is a T junction with a sevo'ed switch on it - if I move this then it moves back automagically

Thermostats are set correctly

 

[kevplumb]

thats the three port valve if you look you can hook the lever open

 

[Bahco]

Do the pipes get hot past the pump, if not try turning up your pump.
Do they get hot up to your mid position valve? , if so set the valve to its mid position. Could be your thermostat is not calling for heat and is knackered or wiring needs checking.

 

[Strangelite]

ok,
pipes get hot boths sides of pump so it is moving though the pump - if I switch the 3 port valve then heat gets transfer round the other pipe - then it switches back. I'll check the locking of the 3 port valve and find a bleed bit later [not there now].

I will double check to see if the main therostat has not been swiched off.

 

[Strangelite]

OK when I lock the valve open the upstairs radiators get hot, one downstairs gets warm and the other one downstairs - nothing.

so we have a bit of progress.

What next ?

[Have moed it back into it's default setting for the time being]

 

[kevplumb]

lock it open and turn the hot rads off

 

[ChrisR]

Pump valves fully open?

 

[Strangelite]

Now, all rads are hot - but only when the 3 port valve is locked in the open position. In the normal position - heat does not get pumped round the system

Thanks for the help so far