Checking Danfoss is oil pump is working

Kingbottler

Kingbottler

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Would any of you kind folks help me discover why oil is not reaching my boiler's burner nozzle?
Is there a surefire way to check an oil pump is functioning?

Following running out of oil, I fired up boiler and it went to lockout.

The fan starts, motor starts and the motor is going round as I took the pump out to check.
Oil is present at the pump and with the bleed valve open, oil spurts out of the bleed valve when the boiler is fired up, but not when it isn't running.

Oil is not reaching the nozzle, but is reaching the bleed point on the burner prior to heading out to nozzle, as when the hex screw is turned oil flows until lockout.
Sparking is fine at electrodes and nozzle is not dirty, so I assume it's not blocked.

The coil on the solenoid seems to be ok as it grabs a screwdriver well.
I'm thinking the pump is the issue or the coupling to the motor?

Any ideas how to progress this fault finding to discover if it's my pump or the coupling.

Many thanks
 
Without a pressure gauge, you cannot be sure. How fast does the oil spurt out of the bleed port?
When you use the word spurt, it suggests to me that you are getting just above trickle. If it splutters, then your oil line may not be bled, either a blockage or a filter that is not bled. Check for that first, and if on a single pipe feed, you should get flow from the bleed without the pump turning.
 
Thanks for responding @oilhead it's a two-pipe setup coming through a tigerloop. I have a pressure gauge but looks like I will need to get a hose to connect this as it's too close to the pressure adjuster so I can't get the gauge screwed in. Anything else that would indicate it is the pump?

Cheers:unsure:
 
Is there oil in tigerloop. Is it frothing.
Have you a spare nozzle to try.
as oilhead has said ,there is only one sure way to check actual pressure.
 
Which burner / boiler do you have?
Drive couplings are often pieces of splined plastic and failure is fairly obvious when you look at them - often the splines have sheared off.
Use a tee piece to connect your pressure gauge to the pump - that may be enough to get it in.
On occasion I have to use an oil syringe to draw the kerosene up to the pump as there is often a fair bit of air in the line.....pumps don't like to be run dry so minimise the start attempts if you can.
John :)
 
Hi @Burnerman Thank you for replying :) It's an ancient Worcester Bosch Heatslave 20/25. The Burner is a Bentone B11-C. I'm sure the coupling was replaced at the last service and it doesn't look too bad to me. Thanks for the tip on T-piece, i'll look out for one of those. :)
 
Is the coupling the small top hat type jobby, with the two plastic lugs? That's one of the more reliable ones, if it is!
John
 
Terrywookfit said:
Is there oil in tigerloop. Is it frothing.
Have you a spare nozzle to try.
as oilhead has said ,there is only one sure way to check actual pressure.
Click to expand...
I honestly haven't checked the Tiger Loop @Terrywookfit, I do have another nozzle I could try, so will give this a go. Thanks for your help.
 
So, update:

  • Changed the coupling, no change still no oil at nozzle
  • Got a pressure gauge extender and it's reading just under 100 psi (I'm now assuming the pump is now working?)

    Any further advice would be warmly welcomed. What next?
 
as you seem to think the coil isworking as it grabs a screwdriver, disconnect the nozzle pipe from the pump, have a container ready to catch oil and try starting the burner. If you get no oil, then either the valve or coil is faulty.
Also, there is a valve in the nozzle pipe by the nozzle holder. Remove this and see if it cures theproblem.
 
oilhead said:
as you seem to think the coil isworking as it grabs a screwdriver, disconnect the nozzle pipe from the pump, have a container ready to catch oil and try starting the burner. If you get no oil, then either the valve or coil is faulty.
Also, there is a valve in the nozzle pipe by the nozzle holder. Remove this and see if it cures theproblem.
Click to expand...
@oilhead thanks giving this a go :)
 
@oilhead this appears to be the problem. No oil is emitting from outlet where the nozzle pipe was connected when restart is pressed. So would you ten say it is the valve in the pump?
 
It sounds very much like a pump valve fault.....if you crack open the ‘P’ port on the pump when the control box asks it to open and there is no oil there, the oil can’t reach the nozzle.
John :)
 
Burnerman said:
It sounds very much like a pump valve fault.....if you crack open the ‘P’ port on the pump when the control box asks it to open and there is no oil there, the oil can’t reach the nozzle.
John :)
Click to expand...
Much thanks John. New pump tomorrow.
 
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