oil burner lockout

[BC59]

installation was checked I assume - I wasn't here to see for myself. It all worked fine as I said in the original post for the first 6-8weeks.

I've replaced the oil pump today and still no joy in fact it's worse! It goes to lockout as soon as it ignites. Photocell clean but not replaced. Fuel clean no contamination in filter, no obvious signs of water either.

Think I'll just settle for putting on extra clothing!

 

[casius66]

I'm not being critical but there are less expensive items you could've changed before the pump (nozzle - filter element - solenoid coil - photocell).
You've not actually proved the pump to be faulty and from previous posts it doesn't seem that you have an oil pressure gauge to set the pump up properly (or the combustion kit to test that it's burning efficiently).
You really would be better off to get someone in to prove what's faulty,fix it and set it up properly.

 

[oilman]

Do you know there is a spark at the electrode points?

 

[BC59]

Sometimes it actually ignites and runs for a few seconds and then locks out. After a short wait I reset and sometimes it tries to fire - with a spark I've looked down the chamber via the plastic viewing plate - and other times it doesn't attempt to fire. If I leave it for a while - an hour or so, it fires up again then lockouts and the same process continues.

I'm totally confused

 

[casius66]

Is the flue blocked?

 

[MANDATE]

Regarding the spark at the electrodes. I had the transformer and electrodes wired up on a bench so I could observe the sparks and make any adjustments needed before fitting it back to boiler and check the end of electrode was in line with face of nozzle.
I had to remove the photo cell and the veiwing glass plus 2 ignition leads plus 1 nut and of course the pipe from pump to nozzle assembley

 

[MANDATE]

Once you have confirmed the transformer electrodes are ok and the problem is still there then the control box/photo cell may well be the cause.
I ran my boiler for about 1/2 hour (from cold) without the control box/photo cell and in that time I stopped it and restarted it a few times.
So I would know any problems would be control box/photo cell related

 

[oilman]

I wouldn't recommend running without the control box. You may get away with it, but if you don't you'll wish you'd used the control box.

 

[BC59]

Thanks for the replies. A further development today; I can't see any fuel in the tigerloop. I'm thinking a blockage or poor suction.

 

[wilhelm]

pump set for two pipe system?

 

[Burnerman]

Call me daft but I actually run these things on the bench, using a remote kerosene supply...this way I can see if the electrodes are actually sparking on the ends, rather than somewhere else, and flame establish can be seen. Naturally you need a gravity fuel supply, which can be easily done by removing the screw within the fuel return port. Good luck again! Cheers John

 

[BC59]

yes, pump set for to pipe operation with the small machine screw fixed in the inlet port.

John, do you still think it's an ignition problem given the lack of fuel in the tigerloop?

 

[casius66]

If you've got no fuel in the tigerloop it suggests a problem with the supply or the tigerloop not priming. It was suggested you check for carp at the filter - have you done this?
It's no good looking for burner problems if you haven't proved the fuel supply 1st.
Did you connect the fuel lines the right way 'round on the new pump?
Does the tigerloop froth when you're trying to fire the burner?

 

[Burnerman]

Its very difficult for me to say if you have an ignition problem, but as has been suggested before, you need to determine that the fuel supply is OK, which I suspect it isn't. Anyway, the electrode tips need to be as near to the end of the nozzle as possible - the draught from the fan actually blows the spark into the fuel spray. However, if they are too close to the flame tube the spark can actually arc to there, away from the fuel spray so ignition doesn't occur. However, you say that the thing does actually light up from time to time so things can't be too far off. The photocell looks at the flame, and if it can see light, it instructs the controller to keep the fuel flowing. To test it, you need a multimeter set to resistance....in the dark the resistance should be very high - in the light it should really be quite low (400 ohms approx). The coil, sitting on top of the pump that operates the internal fuel flow valve, often has 2 coils if it has a 3 wire feed. One coil gives a higher voltage - around 50v - which operates the valve itself. Once the valve has operated, the controller switches it to a lower voltage -around 6v- which keeps the valve in the open position. Normally the pump comes with a new coil though.
The reason I test these burners on the bench is that with a gravity kerosene feed, and no flue pipe, you can obviate these problems if the thing lights up. Just my own quaint way! Good luck! Cheers John

 

[oilman]

Call me daft but I actually run these things on the bench, using a remote kerosene supply...this way I can see if the electrodes are actually sparking on the ends, rather than somewhere else,

The spark can be seen without having to continue to igniting the flame. I have never needed to bench test a burner yet, They all work after I've fixed them. Those I don't bother fixing are beyond economic repair. Very few.

Some photocells will give a minimum reading in light of around 100kohm, so you need to check which type you have.

One coil gives a higher voltage - around 50v - which operates the valve itself. Once the valve has operated, the controller switches it to a lower voltage -around 6v- which keeps the valve in the open position. Normally the pump comes with a new coil though.

Pumps with twin coils are made by Riello, Those that have the coils supplied are made by Danfoss, and are a mains operated single coil. Riello coils rarely fail, Danfoss coils often do. There are Suntec pumps which use single coils, but are less common.