Radiators Cold and I'm tearing my hair out! Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[gwalsh]

We have a traditional vented system.
Oil boiler is working fine and heating the system.
The pump has been replaced and primed and working fine.
We have two motorised valves, one feeds circuit into tank, one feeds circuit into radiators. Both can be manually over ridden and have been to no effect.
The circuit is hot but does not heat up the water in the tank or the radiators.
I can not find any air in the system, none in any of the radiators also drained air just above pump.
Have drained the system a couple of times and refilled, not any noticeable sludge.
No magnets appear to be sticking on any of the copper pipe work that I can get access to.
Any ideas? I have tried everything I can think of!

[dodgepott]

yeah have you fitted the pump the right way round ? have the primary flow and the return been correctly connected to the boiler? can the air be vented from the boiler ok. Are the pump valves fully open or partially blocked.If an old pump fit a new one.Dont pull your hair out we have all been there.

[gwalsh]

The system was working stopped last week, so the original pump was fitted the correct way around and now the brand new one is. I presume the primary and return are connected to the boiler correctly as I haven't touched them. I will try to see if I can vent air from the boiler, but the pipework either side of the pump gets very hot so I presume there is no air in that part of the circuit. I do have an issue with the pump valves! They are old and not fully open, can I buy 1" pump valves anywhere? Or do I need to replace the copperwork?
Thanks for the help, you have given me something to try.

[gwalsh]

New Pump, New Valves (fully open), no air (I can find).

But no change. (Running out of hair)

[dodgepott]

yeah the feed and expansion tank check and see if the water is circulating in the tank .sometimes the water pumps over the tank via the expansion pipe and back down the cold feed. this may be caused by a sludge problem.it sounds to me that the heat is unable to dissipate from the boiler.IF you are sure that the pump is working ok and that all valves are open it may be worth giving the pipe work a blast with the water main connected to the mains water supply with a hose pipe on to the drain valve needs 2 people to do this. 1 person on the tap and the other person checking f&e tank and system. this should move any air or muck in the system. good luck

[dodgepott]

Yeah i have just had another idea make sure the system is full of water and the cold feed is not blocked. any auto air vents are working .check high points in system for manual air vents.
ps you will be bald after this.

[gwalsh]

End of weekend update!

When the system has been bled without the boiler running but the valaves open and the pump running, if I open the drain valve at the bottom of the return to the boiler there is a very small or no flow of water.

I presume I have a blockage in the pipping somewhere, any ideas how this can be shifted without opening up the floor and walls?

[ALDA]

GW,

COULD BE PRIMARY FLOW PIPE IS BLOCKED OR AIR LOCKED.

TRY ATTATCHING CW MAINS HOSE TO VENT PIPE OVER HANGING F&E TANK.
SLOWLY INCREASE PRESSURE AND WATCH FOR ANY FLOW OF AIR OR SLUDGED WATER COMING FROM FEED PIPE INTO BASE OF F&E TANK.

(BE SURE THAT THERE IS CAPACITY IN TANK TO TAKE THE ADDED WATER AND ENSURE OVERFLOW IS CLEAR BEFORE YOU START).

THIS MAY SOLVE YOUR PROBLEM.

ALDA.