Oil boiler on lockout after new motor fitted

[Burnerman]

It does sound like the fuel could be draining down away from the burner, to be replaced by air which naturally doesn't exactly burn well.....however the valves in the pump should prevent this.
If the burner was to run for a few seconds and then lock out, this indicates a photocell problem, likewise if the pump solenoid failed then that would also cause the flame to fail.
All of these things are easy enough to check......if I suspect air ingress I have a clear polythene tube so I can see any air bubbles, and there's a special 'magnetic wand' that can detect solenoid operation.
We have our fingers crossed for you!
John

 

[oilhead]

If motor is now spinning every time, then this should now be able to be discounted. Has the engineer tested the vacuum of the oil pump? This will prove its integrity.
One further point, since you referred to a new oil tank and a longer run of pipe to it, what diameter is the supply pipe, and what height is it expected to lift ?

 

[Ashtara]

It's a 10mm pipe. Not sure how high the lift is I don't think it's that much but there is a tiger loop.

It only locks out from cold then runs fine for the rest of the day

 

[Boilerman2]

It could be something as simple as a poorly made compression fitting near the boiler (above the height of oil in the tank, this would let air in, but not allow oil to leak out, a very common problem!

 

[oilhead]

Are all joints visible? It is possible that there is a joint in the 120ft that is leaking slightly and the small amount of oil being lost does not show up in the tiger loop. Have you watched the tiger loop on initial start up? Are there any bubbles evident for a few seconds?

 

[Ashtara]

Tiger loop moved on Friday. Worked fine over weekend but nothing this morning.

Won't fire up at all now, motor is running, here a slight click and then lockout. No firing up at all.

Back to engineer me thinks - on the bright side at least it's completely gone now so he can at least see what to do to get it started

 

[Burnerman]

Therefore it would seem that either the pump can't draw its fuel (the pump vacuum integrity has been mentioned) or the ignition spark has failed......maybe the tiger loop was fine after all?
This is becoming one of the finest soap operas of the day (at your expense, sadly) and we can't wait for the next episode......surely there's a conclusion soon!
John

 

[Ashtara]

Yep, I am thinking tiger loop was fine too after all. But hey these things have to be ruled out.

Pump was replaced in November annoyingly so didn't last long.

Proving costly yes - but cheaper than a new boiler and quite honestly as long as it finally works I will be happy

 

[Burnerman]

I'm sure that the fault has been identified somewhere here - although its dead easy to be clever and smug behind a lap top!
Its probably not relevant but I wonder what others thoughts are regarding a 10mm feed over that distance - or whether a 15mm would have been better......thats out of my league to decide.
John

 

[Ashtara]

Engineer back round tonight.

Have a feeling he too is thinking its the pump at fault. Just annoying as forked out money to have that replaced in November (by the old engineer) and now it's playing up.

 

[Burnerman]

Pumps are reliable and can last for years.....but only if all the filters are kept clean and more importantly, free of water - that gooses them in no time.
My own theory is so long as the pump is capable of providing more pressure than the burner is required to have, and the vacuum side is performing well too (both are easily checked by appropriate gauges) then the pump is fine for future service.
John

 

[Ashtara]

I am sure he checked the pump pressure with his gauges when he fitted the tiger loop but will ask him if he checked the vacumn when I see him tonight.

 

[Terrywookfit]

I'm sure that the fault has been identified somewhere here - although its dead easy to be clever and smug behind a lap top!
Its probably not relevant but I wonder what others thoughts are regarding a 10mm feed over that distance - or whether a 15mm would have been better......thats out of my league to decide.
John

10 mm Pipe is max size for a Tigerloop. (Bigger is not better, You need to coat the walls of the pipe to create suction).
It is the lift height, not length that is important.
If memory serves me correctly for a domestic sized burner, a Tigerloop will give a 3.5 m lift with a 100m suction line with no problem.

 

[oilhead]

Terry is right, bigger pipe diameter is counterproductive; imagine the difference in drinking a pint of milk through a drinking straw, and then using a kitchen roll core to do the same job. The weight of liquid in the larger pipe is too much for the pump to pull.
From my recollections, the 100m / 3.5mt lift is for 8mm pipe. If however, there is a gravity feed to the base of the lift over the length, then 15mm would get it there without resistance, and you can use an 8 or 10mm pipe just for the lift.

 

[Burnerman]

Thanks both - that makes complete sense.
John