Bentone Burner Fireup Problem

21 Apr 2016
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I have a Bentone Burner Sterling 128 app. 13 years old.

Recently. the burner has been very difficult to start in the morning ofter requiring 4 or 5 resets.

I noticed that there was a leak in the oil feed to the burner. I replaced the oil filter, the fire valve and re-tightened the pipe connections.

I attempted to fire up the burner. It fired up normally but cut off after a few second. I then noticed that there was a lot of smoke coming out of the boiler.

After a short time, I attempted to fire up the burner again. There was no trace of a flame.
Normally, the burner fires up approximately 30 seconds after pressing the reset button.
and I hear a relay click.

Now, however I am hearing a relay click after approximatery 15 seconds, followed by another click after approximately 30 seconds - bur no flame.

I would be grateful if anyone could suggest what the problem might be!

I removed the burner from the boiler and replaced the nozzle. which was rather gummed up.

Is it posible that the ignition control unit is faulty

Many thanks

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It is possible that the ignition transformer has called it a day, but there are other reasons.....can you pull the burner out of the boiler and look for the electrode spark?
If you take the coil off the top of the oil pump, there’s no chance of ignition but the spark will still be there.
Also check the photocell is in its correct place.
John :)
It is possible that the ignition transformer has called it a day, but there are other reasons.....can you pull the burner out of the boiler and look for the electrode spark?
If you take the coil off the top of the oil pump, there’s no chance of ignition but the spark will still be there.
Also check the photocell is in its correct place.
John :)
Don't remove the coil, just disconnect the plug. If you remove the coil and energize it, you may find it implodes on itself without a core load.
If you have been resetting frequently in quick succession, you have probably cooked the ignition transformer.
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I'm slightly confused. I accept your opinion that I have probably cooked the transformer.

To check for a spark, can I simply remove the burner from the boiler by removing power and disconnecting the oil feed. Then, could I simply power the burner on a bench and press the start button and check for a spark? Am I wrong in thinking that this is all I need to do?

I do not really know what is meant by removing the coil!
Would the 50 second lockout period not protect the transformer from damage?

I would be very grateful for your help.

By all means you can remove the burner from your boiler for a bench test, you’ll need a mains hook up to test for a spark.
Here’s an approximate run of events when you switch the burner on:
The motor starts up, the fan connected to it purges the flue ways with fresh ignition spark is present at the same time and of course the pump is spinning too.
After about 8 sec, the oil supply is electrically turned on by the solenoid coil on top of the pump and the burner should light.
The photocell sees light ( flame) and keeps the oil flowing and the ignition spark stops.
If you unplug the solenoid coil ( cheers Terry) the burner will still spark but of course the oil supply can’t be turned on, so it will go to lockout after a few more seconds.
The ignition transformer does suffer from heat if its constantly being commanded to spark, I’ve known them goose the control box at the same time. A faulty transformer may have a bulge on its side.
John :)
Many thanks John for your help and explanation of the boot up sequence

Getting back to my problem, I replaced the ignition unit but the problem still persisted.

I removed the burner from the boiler and powered it up on the bench. There was no spark visible.
It seems to me that the problem lies in the Control Unit - LOA24 173A27. What is your opinion?

I installed the Boiler and Burner myself in 2003. It is becoming difficult to get parts for the Burner. The Boiler is a Firebird 'S' Range 120/150.

My existing burner runs on Gas Oil. If I replace the burner in the Summer, should replace it with a
gas oil burner or, would kerosene be better?

I have an electronics and electrical background but long since retired. However there is no information available on the inners of the ignition unit or the control unit.

Any advice would be most welcome

Make sure the photo cell is kept in the dark when testing.Check voltage to igntxfr or energise with a jumper control box removed.
Can you break out the multimeter to test your photocell (LDR by another name). Look for a very low resistance in light and very, very high in darkness.
When I'm testing, I hold the photocell in a clenched hand and as soon as the burner lights I let it see the flame.
I can't really see the need to replace your burner but I do feel that kero is the better fuel than gas oil, although its a long time since I've seen a burner using this. The adjustment of pump pressure, nozzle size and a full gas analysis is usually required.
John :)
It's Ireland ……...They love a drop of red over there !!!

I have yet to hear a photo cell /resistor called a LDR.!!
If you rub your hand on the transformer you may feel a bump if you do then it’s goosed. Bob
With the control box removed, disconnect the transformer lead and connect direct to live. Switch on burner and check for sparks. If you get sparks, reconnect to the correct terminal, replace the control box, disconnect the transformer lead from the transformer and check for current with your multimeter. If you get power, your start up problems are not spark related.
If the problem is only on start up, running on 35 sec oil, it may need a preheater to the nozzle. On low throughputs, the fuel does not atomise properly, especially in colder weather.
Hello John

Following your suggestions, I checked the Photocell

Resistance with no light = 120K
Resistance with Led Torch shining into face = 1K

I powered up the unit with the photocell covered and there was still no spark.

Bearing in mind, that I have already replaced the ignition unit (transformer?), it appears the control box is suspect!

Talking about the transformer, the last time I replaced one was on my previous burner. It was a Selectos. The core of the transformer was an iron laminated one. It stepped up the mains from 230 volts to 9000 volts app. . It carried a death warning. I still have a spare!

Many thanks to yourself, Bob and Oilhead for your help.

Since, I have replaced the transformer unit, is it quite safe to connect 230V across the removed unit and see if a spark is produced?
For sure, that's how I test them too but I do take care to maintain a correct gap for the spark.
Are you happy with the electrode position on the burner? The spark occurs behind the nozzle and the draught blows the spark into the oil spray.
I do suspect the control box, and the fact that the boiler produced loads of smoke (your first post) would indicate unburnt kerosene in the fire box.
I'm not home right now, but I'll test a known good photocell tomorrow and post back....I would have expected the resistance in the dark to be much higher but don't quote me on that one!
John :)

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