Inter 2011 Burner and Danfoss BFP21L3 Pump 3 Plumbers Later

[Frank0241959]

My old Myson 60/80 Boiler has an Inter 2011 Burner, Brook Compton motor and a Danfoss BFP21L3 oil pump. I think it is about 20 years old. It works for about 5 – 10 Minutes then goes to lockout after the burner has fell silent. I have oil, tank is high and oil comes out of feed pipe steady.

If I wait a couple of minutes I can press the lockout button and get another 5 - 10 minutes running out of it.

1st Plumber/Boiler guy. Tried to get it fixed and had explained the fault to the first plumber/boiler guy but he said it needed service and fitted nozzle in burner. Second visit as still not working, fitted new filter. Still the same.

2nd Plumber/Boiler Guy. Explained same symptoms and described fault, he serviced it and put new nozzle in burner, said it was overheating. Still the same. Came back again and said he changed solenoid.

3rd Plumber/Boiler Guy (OFTEC registered) Explained same, he checked electrodes for crack, checked nozzle and cleaned out boiler where baffles are, stayed longer and witnessed it going off and on. Felt Oil pump and said it was getting too hot. He suggested a new burner unit approx. £600.

I am waiting for him to come back to me because he said supplier can't find a replacement burner as my boiler is so old. That was a week ago and I still have no heating or hot water.

Now I am no boiler engineer, but am an engineer I asked if any of the bits were replaceable first before buying whole new burner and he said no, too fiddly and may not fix fault. When he was gone I took grub screws out of Danfoss oil pump where it goes in motor and removed it. I felt spindle and it feels a little sticky, jumpy and not what I would expect for smooth running.

I went online and got an identical oil pump for £40.

Question: I would like to know if anyone can advise feasibility of fitting this myself, I am happy with connections and bleeding but am wondering if there is some pressure setting I have to make before testing it?

Question: I looked at a EOGB x400 Burner which looks like it fits and only costs £280 on ebay. Does anyone know if I can fit this unit if all else fails or can recommend another manufacturer of model that will fit?

I would dearly like to use a local boiler engineer but my experience over 8 weeks and three engineers has cost me more than a new burner and I am no further forward and freezing cold.

 

[Tibbot]

You need an experienced oil boiler engineer (OFTEC or not doesn't matter). Most of these guys only service and repair and do not install or plumb anything. They are about in your area. It seems you may be employing chancers who charge cheap to get in then experiment at your expense.

If you DIY you will be wasting money as you have no more knowledge than they do.

 

[Burnerman]

If you do decide on the diy route, please be aware that the new pump will not be set to the correct pressure (usually somewhere between 100 and 140 psi - all boilers differ) and afterwards a flue gas analyser will be needed to adjust to the correct CO2 level (usually between 10.5 and 11.5%).
A replacement burner will physically fit, but again will need setting up - and this includes the length of the blast tube.
As for the original problem, we can only guess but the motor start capacitor can fail due to heat......the pump should turn smoothly though.
You really need to be present when the burner tries to start but fails.....the usual sequence is for the motor to start and spin for around 8 sec (purging the flue with fresh air, and the ignition spark is present at this time) and then the oil is electrically switched on by the solenoid on top of the pump. A photocell looks for light (flame) and if it sees light, it keeps the oil supply switched on.
John

 

[Frank0241959]

Thanks Tibbot, I hear you but how can you get truly experienced people. All of them said they had been working on oil boilers for years when I rang them. the first two attended when I was not at home, so on the third try I made sure I was here and tried to suggest ideas but was ignored in preference to a whole new burner fit.

What puzzles me is why they won't change parts or try the process of elimination, surely some part is failing as the burner gets hot?

As you say I have no more knowledge than they do but I do have perseverance and will find someone to help me. Its darn cold here in Suffolk on an evening and they don't give a monkeys..

 

[Andy4444]

Assuming your fault diagnosis is correct you will after fitting your cheap pump (I couldn't source a BFP fir less than £40) need the relevant combustion information to set up pump pressure/air setting, a smoke gun to measure smoke, oil pump pressure guage to measure oil pump pressure and if you are unable to determine the correct flame picture a flue gas analyser to measure correct and safe combustion. These bits of kit will nit leave you much change out of £800 (not including the time you will have to allocate in learning how to properly use the equipment).

You have been unlucky in sourcing 3 boiler guys who have not been able to diagnose the fault. An Inter 2011 going to lock-out after 10 minutes would not present too many problems for an experienced oil boiler engineer to be honest . The right person should also carry most of the parts for the burner.

 

[Frank0241959]

Thanks John, I know the burn time has decreased over the last few weeks before this short burn. It used to run for about 25 minutes before lockout. then as now you could reset lockout and get another 25 minutes out of it.

I asked about my spark, photocell which he said worked OK, in fact he said it had a good spark.

I have measured the blast tube length and can get the same, the pressure setting will be my problem.

My brother in law is gas safe but not in this area so I assume his equipment could be used to do flue gas analysis on an oil burner.

 

[Frank0241959]

The right person should also carry most of the parts for the burner.

Thanks awowen, That's what I would have hoped also, surprised they are not like mechanical engineers who would always attend a job with stock.

Switch out a spare part and try to isolate the issue. I am not keen on ringing random people anymore as I have had such bad luck. But there is sure to be a good engineer who could fix this.

 

[Burnerman]

Just a couple of pointers (speaking as an engineer, but not a central heating one )
If you have the motor on the bench, it should spin freely and quietly (bearings 6202zz often enough) and it should be much too powerful to stop with the fingers!
The capacitor tells the motor which way to spin from stationary and if its faulty they often swell or blacken.
The spark igniter transformer also tends to distort if its been cooked, too.
Have you checked the filter in the old pump (underneath the allen bolted cover?)
John

 

[Boilerman2]

It occurs to me that no one has checked the in-line oil filters, partial blockage of oil filters will cause the symptoms you describe

If you need a help send me a personal message - my company are based in Suffolk and specialise in service & repair (OFTEC) registered (for what it is worth!)

 

[Frank0241959]

It occurs to me that no one has checked the in-line oil filters, partial blockage of oil filters will cause the symptoms you describe

I have sent you PM BTW.

 

[oilhead]

No-one has suggested that the fault may lie with the pump solenoid. Classic symptoms described.
Try changing the solenoid off your 'new' pump before doing anything else.

 

[Andy4444]

No-one has suggested that the fault may lie with the pump solenoid. Classic symptoms described.
Try changing the solenoid off your 'new' pump before doing anything else.

Solenoid already changed by plumber 2

 

[oilhead]

I'm sure Boilerman will sort it out.

 

[Frank0241959]

It occurs to me that no one has checked the in-line oil filters, partial blockage of oil filters will cause the symptoms you describe

If you need a help send me a personal message - my company are based in Suffolk and specialise in service & repair (OFTEC) registered (for what it is worth!)

Can you get in touch please Boilerman2? I have the Oil pump here, boxed brand new and waiting to go on. Many Thanks.

 

[Frank0241959]

Update for those who made suggestions and offered advice:

Clearly when I checked the new Danfoss BFP21L3 oil pump off eBay £35.40 + postage. The Solenoid Plumber 2 had fitted on my oil pump was a second hand one and not wishing to investigate any further I fitted the new pump and Solenoid.

I had no way of setting pressure so I so I screwed allen screw in on old pump right in and counted turns, that equated to 2.25 where it bottomed out.

I then screwed allen screw on new pump in until it bottomed out, then unscrewed it 2.25 turns. Put the plastic drive on new pump spindle and connected it all up after screwing grub screws in on motor housing to pump. I did this only as a benchmark to get it going and test other fault.

Purged it and fitted it back to boiler, with anticipation I called for heat on the boiler and it fired within about 8 seconds burned perfectly for 15 minutes, NO flame out or lock out so I turned it off.

Took burner back out had a real good look at all connections and made sure it was sound as far as any leaks go, had'nt got the oil pump pushed right home against the electric motor and it made a slight noise so levelled that up and pushed it home properly securing it with the grub screws.

Fitted burner back to boiler and noise had gone, just a pure fan and burner sound now, have run it for an hour with no signs of any problems. Checked the flue out side, smells nice, no smoke or hunting sound.

Moral of the story in my case is: Some of you mentioned Solenoid as common fault, I thought I had a new one fitted by plumber 2, Should have listened to you lot and tried that first. Luckily I got pump cheap so happy I have 2 new elements fitted.

On the up side I have new engineer Boilerman2 who lives locally so will use him in future for servicing.

(I will get the oil pressure and flue gases checked professionally as soon as possible)

Thanks for your help oilhead awowen Burnerman Tibbot