oil-fired boiler pump

[wb]

I thought my fuel system was air-locked. In fact, it appears that there was a blockage in the fuel pump - the plunger wouldn't move. Of course when I poked into the hole (as you do!!) the plunger popped out, in pieces (as it would!) I reammembled it (using my initiative - and this is probably the weak link in the process!) and replaced it back into the pump. Fuel now passes through - but to excess ithink, as the boiler only fires (very loudly) for a short time before blowing out. Any ideas or has anyone a diagram of this pump? It'ss a fairly old system (installed about 30 years ago; boiler casing says Thorn, motor says Compton..?, fuel pump has Danfoss? on it and there is a label with an arrow and S & R at either end.

[Michael Chare]

Go and look on the Danfoss Web site for a suitable replacement pump, then buy one from someone like HRPC.

The pumps dont last for ever. (well not in my house!)

Also buy a pressure gauge with T piece and maybe a high pressure flexible hose.

Install new pump and set to work at correct pressure.

[Mike]

And then possibly reset the flame settings as well.

[John]

I think you have buggered up either the solenoid valve or the pressure regulator since most Danfoss pumps are gear type not plunger. You could save yourself a lot of wasted time and grief by simply replacing the Danfoss pump now instead of buggering about for ages and then buying a replacement anyway. The usual old domestic Danfoss was the MSLA which was superseded by the BFP21L3 or BFP21R3 depending on the direction of rotation (the L being most common) Source one from Parts Centre in your locality (was HRPC) You are going to really struggle to set the burner up again unless you know the original pressure setting and have a flue gas analyser kit.