air in system

[Jimmnycricket]

I was wondering if anybody can help. I have a brand new Y plan central heating system. ie. New Remeha boiler, pump, 3 way valve, hot water cylinder, rads and new pipework.
There is air getting into the system somehow - no leaks- checked every joint when hot and cold- so boiler cuts out after a while even though heating thermostat calling for heat. Then boiler comes on after a short while.

 

[Homesafe]

A basic answer considering I'm not there is it sounds like the flow is restricted and the system needs a by-pass( if one not fitted ) or balancing, could you say how long it stays on for?

 

[45yearsagasman]

Brand new??? Is it open vented or a sealed system.(OV usually means a small header tank in loft) Why not involve your installer?

 

[Jimmnycricket]

It is an open vented system ie small header tank in loft. Installer is involved and is at a loss as what to do.
A bypass was fitted.
It has been balanced.
The expansion pipe has been extended so that it sits in the water in the header tank just incase the system was sucking in air through it.

When the heating thermostat calls for heat in the morning the boiler comes on for about 5mins. Then cuts out. Then after about ten mins it fires back up and then it continues to behave normally ( I go to work but wife says it seems ok).

The system's pump is connected to the boiler and has over run. ie. the pump continues to run for about 3mins after the boiler goes out.

 

[HERTS P&D]

It is an open vented system ie small header tank in loft. Installer is involved and is at a loss as what to do.
A bypass was fitted.
It has been balanced.
The expansion pipe has been extended so that it sits in the water in the header tank just incase the system was sucking in air through it.

NO NO NO. The expansion pipe should not be in the water in the expansion tank. It will act like a radiator.

Andy

 

[leakydave]

NO NO NO. The expansion pipe should not be in the water in the expansion tank, there should be an air gap even with the f and e tank at its highest level

 

[45yearsagasman]

Air or hydrogen?

 

[WedgeAntillesRed2]

If its hydrogen you should be able to test with a match!!!!!
Oooooops, done it again. Are the Rules on this forum for natural gas and lpg only!
Is it really a brand new system! Internal corrosion producing hydrogen unlikely. Are you getting air/hydrogen build up in rads?

 

[Jimmnycricket]

It is brand new system. Every thing is brand spanking new including the pipe work

On the advise of Andy I will take the expansion pipe out of the water in the header tank.

 

[twgas]

sounds to me more of a circulation issue, does the hot water work?have the rads ever heated? are the pump valves open?

 

[plumbswe]

Could be a plumbing issue. The vent, inlet and pump should be within 150mm and be in that order. Vent Inlet Pump. Check the system has been installed with this method. Air could be getting drawn down the vent in to the system if its plumbed in wrong.