Hi,
I have a HRM wallstar 12/15 : 11 (Date 07/04 I reckon, installed late 2004). It has an intermittent fault where it sometimes fails to run requiring someone to go outside and push the red button (usually when it is raining!).
There is a lot of air in the plastic pipe. I get rid of the air by wiggling the pipe when the boiler is running but it comes back over time. The assumption is that this large air bubble is the cause of the bad running, the pump suck air and so the burner doesn't light. It certainly is a new behaviour that occurred the same time as the bad running started.
So HRM tell me this is likely to be the non-return fire valve leaking down the shaft. Get a new one and new clear oil pipe - still does it. HRM say the shaft needs oil on it so pull it back and forth. Try that still the same. Take valve apart and get kerosene on shaft, no change. Grease shaft with vaseline - no change.
I've added a non-return valve at the tank thinking that is the problem is the oil dropping back then that would stop it and a non-return valve full of oil is likely to work better than one trying to stop air. Still get the air bubble so the air must be sucked in when the boiler is running.
I've applied La-Co SlicTite Pipe Thread Compound (which is rated for oil) to olives and threads. The cone joints of the clear oil pipe have been dry and with a smear of vaseline (I didn't want PTFE compound to get into the oil line).
Paper oil filter at the tank has been changed (and the olives there giving a coat of compound.
HT leads and ceramic holder for electrodes have been inspected (cracking of the ceramic can cause ignition failure). Just in case the large air bubble is a red herring.
I'm at a loss as to what could be causing this. I don't think it can be the pump because then the air bubble would start at the pump and it is in the centre of the clear oil pipe. There is oil after the bubble going to the pump.
The air bubble is consistent with air being drawn in with the oil and then the air staying at the highest point.
I seem to be left with either the new clear pipe is duff or I have a crack in the (copper) oil feed line which is too small to let oil out, just air in, but not enough air to stop the boiler running instantly.
The oil has been in the tank since the last top up in June, in case that is relevant.
Any suggestions?
P.S. Pump coil has also been changed. No sign of bulging on HT transformer.
I have a HRM wallstar 12/15 : 11 (Date 07/04 I reckon, installed late 2004). It has an intermittent fault where it sometimes fails to run requiring someone to go outside and push the red button (usually when it is raining!).
There is a lot of air in the plastic pipe. I get rid of the air by wiggling the pipe when the boiler is running but it comes back over time. The assumption is that this large air bubble is the cause of the bad running, the pump suck air and so the burner doesn't light. It certainly is a new behaviour that occurred the same time as the bad running started.
So HRM tell me this is likely to be the non-return fire valve leaking down the shaft. Get a new one and new clear oil pipe - still does it. HRM say the shaft needs oil on it so pull it back and forth. Try that still the same. Take valve apart and get kerosene on shaft, no change. Grease shaft with vaseline - no change.
I've added a non-return valve at the tank thinking that is the problem is the oil dropping back then that would stop it and a non-return valve full of oil is likely to work better than one trying to stop air. Still get the air bubble so the air must be sucked in when the boiler is running.
I've applied La-Co SlicTite Pipe Thread Compound (which is rated for oil) to olives and threads. The cone joints of the clear oil pipe have been dry and with a smear of vaseline (I didn't want PTFE compound to get into the oil line).
Paper oil filter at the tank has been changed (and the olives there giving a coat of compound.
HT leads and ceramic holder for electrodes have been inspected (cracking of the ceramic can cause ignition failure). Just in case the large air bubble is a red herring.
I'm at a loss as to what could be causing this. I don't think it can be the pump because then the air bubble would start at the pump and it is in the centre of the clear oil pipe. There is oil after the bubble going to the pump.
The air bubble is consistent with air being drawn in with the oil and then the air staying at the highest point.
I seem to be left with either the new clear pipe is duff or I have a crack in the (copper) oil feed line which is too small to let oil out, just air in, but not enough air to stop the boiler running instantly.
The oil has been in the tank since the last top up in June, in case that is relevant.
Any suggestions?
P.S. Pump coil has also been changed. No sign of bulging on HT transformer.