Open the screw on the front of the pump to release any air...fire it up for 10 secs then stop and you should hear all the air rising up to your system bleed point (you may have more than 1). Repeat until working.When you are bleeding the pump make sure it still turns freely by moving the spindle nut.
Air lock (I think)
- Thread starter fulcrum
- Start date
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W
wilhelm
Thanks Ollski
I had tried that and have repeated but no joy. Pump is spinning. Having read as much as I can i think the cold feed to the boiler is blocked. I have water in the rads though. Think I might need some pipe cutting or maybe I am a pessimist.
thanks again though.
I had tried that and have repeated but no joy. Pump is spinning. Having read as much as I can i think the cold feed to the boiler is blocked. I have water in the rads though. Think I might need some pipe cutting or maybe I am a pessimist.
thanks again though.
Have you tried this ?
Drain the system down again, open all radiators vent & on pump then fill it again at the same time, you may need a hand doing this and get ready for water leaking !
ps: also do you have a motorized valve ? if so open it to manual as well.
Drain the system down again, open all radiators vent & on pump then fill it again at the same time, you may need a hand doing this and get ready for water leaking !
ps: also do you have a motorized valve ? if so open it to manual as well.
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I had this problem recently after draining & refilling my system, flow pipe from the boiler was hot, return pipe remained cold, I assumed the pump didn't have enough head to push the air out.
What worked for me was bleeding the system bit by bit, first HW cylinder alone, then CH alone, one radiator at a time (closing all radiator valves but one, bleed that radiator, then move to the next...)
What worked for me was bleeding the system bit by bit, first HW cylinder alone, then CH alone, one radiator at a time (closing all radiator valves but one, bleed that radiator, then move to the next...)
Air in the radiators is easy to bleed off and so is the pump, but if the air lock is in the pipe work it is more difficult, because the air will compress and there is too much resistance for the pump to push the water around.
One method of reducing the resistance and freeing any air, is to remove a downstairs radiator and run off a couple of bucketful of water from the radiator valves, relying on the pressure from the cold water tank.
Don't forget the tank will only be a small one and you don't want to run off water quicker than the tank can fill, or you'll be allowing air in, so not so fast OK!
I use a bit of kit comprising 5ft clear plastic tubing with each end fitted with a 'tap connector' beside running off some water from the flow and return pipes, you can connect both ends up and observe the flow through the tubing before refitting the radiator.
All I can say is that it worked for me.
You can tell if you have a blockage when running the water off, because water will soon cease to flow out from one or both the valves.
It would be even better if the other radiators had their valves closed.
One method of reducing the resistance and freeing any air, is to remove a downstairs radiator and run off a couple of bucketful of water from the radiator valves, relying on the pressure from the cold water tank.
Don't forget the tank will only be a small one and you don't want to run off water quicker than the tank can fill, or you'll be allowing air in, so not so fast OK!
I use a bit of kit comprising 5ft clear plastic tubing with each end fitted with a 'tap connector' beside running off some water from the flow and return pipes, you can connect both ends up and observe the flow through the tubing before refitting the radiator.
All I can say is that it worked for me.
You can tell if you have a blockage when running the water off, because water will soon cease to flow out from one or both the valves.
It would be even better if the other radiators had their valves closed.
I was wondering if it possible to connect the water main pressure hose inside the F&E outlet and a short blast out with the drain point open, if it sludge/blockage then that will push further down creating more problem. I suppose you could do the same by connecting it to the radiator valve and blast it back to the F&E tank, not sure if it can be done this way, see what the others think.MANDATE said:
Alan
I am going to try your suggested method of 3 April (please help, I am still cold) to night.
Failing that plumber coming Thursday though I was not impressed by 'I will fit a new rad and fill it up and it should be OK. We shall see.
I am going to try your suggested method of 3 April (please help, I am still cold) to night.
Failing that plumber coming Thursday though I was not impressed by 'I will fit a new rad and fill it up and it should be OK. We shall see.
good news
AlanE's suggestion in a previous post has partially worked. I now have hot water and heat to 2 out of 6 radiators . The other 4 are not getting even slightly warm but have not given up yet. I will bleed them again. (I have opened all the valves thank you.) I am also worried the boiler fan is noisier than I recall but hell maybe thats me being paranoic.
I can now have a hot shower. For all your help I am immensely grateful.
AlanE's suggestion in a previous post has partially worked. I now have hot water and heat to 2 out of 6 radiators . The other 4 are not getting even slightly warm but have not given up yet. I will bleed them again. (I have opened all the valves thank you.) I am also worried the boiler fan is noisier than I recall but hell maybe thats me being paranoic.
I can now have a hot shower. For all your help I am immensely grateful.
Hi Masona!,
I've considered applying the mains pressure to a radiator valve or even a drain plug and came to the conclusion it would not work.
The way I see it is that the 'flow' pipe leaving the boiler becomes the 'return' pipe going back to the boiler with the pump pushing the water in one direction only, making a complete circuit
Now the two vertical pipes ( water pipe from tank & expansion/overflow pipe) both connect to the above mentioned circuit. Where they connect may only be inches apart or it could be a few feet.
Now if there was a blockage say in the water pipe from the tank and the mains supply was applied to the drain or radiator valve it would take the path of least resistance and water would exit from the expansion/overflow pipe.
If the blockage was in the 'flow' or 'return' pipe it would still by-pass the blockage by going in the opposite direction and exit through one the vertical pipes.
Even if the expansion/overflow pipe was temporarily capped and water came up through the pipe from the water tank there is no guarantee the blockage has been moved.
If the mains was applied to the overflow pipe it could still by-pass the blockage.
The secret to this problem I believe is to alternate the direction of the water being pumped to loosen and flush any sediment away.
Some years ago I purchased small black & decker plastic pump (£10) that will take clear plastiic tubing on inlet and outlet and is for use with an electric drill and I often wonder how effective it would be in curing the blockage problem.
I've considered applying the mains pressure to a radiator valve or even a drain plug and came to the conclusion it would not work.
The way I see it is that the 'flow' pipe leaving the boiler becomes the 'return' pipe going back to the boiler with the pump pushing the water in one direction only, making a complete circuit
Now the two vertical pipes ( water pipe from tank & expansion/overflow pipe) both connect to the above mentioned circuit. Where they connect may only be inches apart or it could be a few feet.
Now if there was a blockage say in the water pipe from the tank and the mains supply was applied to the drain or radiator valve it would take the path of least resistance and water would exit from the expansion/overflow pipe.
If the blockage was in the 'flow' or 'return' pipe it would still by-pass the blockage by going in the opposite direction and exit through one the vertical pipes.
Even if the expansion/overflow pipe was temporarily capped and water came up through the pipe from the water tank there is no guarantee the blockage has been moved.
If the mains was applied to the overflow pipe it could still by-pass the blockage.
The secret to this problem I believe is to alternate the direction of the water being pumped to loosen and flush any sediment away.
Some years ago I purchased small black & decker plastic pump (£10) that will take clear plastiic tubing on inlet and outlet and is for use with an electric drill and I often wonder how effective it would be in curing the blockage problem.
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