Worcester heatslave 25 - no oil pressure

[bruce3]

So based on that it could be a solenoid related issue? As I see it, we have oil to the pump and in operation oil shoots out of the pump bleed point (which doubles as the pump pressure measuring point) which implies that the pump is pressurising. There is no oil pressure at the burner (I disconnected as you suggested and there it is just vaguely wet with oil).

Might it be that the (old) control box is failing to activate the (new) solenoid? Anyway to check? Can the solenoid be hot wired to confirm its activation one way or another?

 

[spraggo]

So based on that it could be a solenoid related issue? As I see it, we have oil to the pump and in operation oil shoots out of the pump bleed point (which doubles as the pump pressure measuring point) which implies that the pump is pressurising. There is no oil pressure at the burner (I disconnected as you suggested and there it is just vaguely wet with oil).

Might it be that the (old) control box is failing to activate the (new) solenoid? Anyway to check? Can the solenoid be hot wired to confirm its activation one way or another?

You can check if the selenoid valve is working by listening for an audible click from it within seconds of the boiler being swiched on.

You can also test it for continuity between the brown and blue wires, however if you say it is a new one then I suggest you replace the control box with new

 

[bruce3]

Difficult to tell if the click is from the control box relay or from the solenoid. New control box should arrive tommorrow and likewise a new oil pump to electric motor coupling.

I'll post the results.

Meanwhile if anyone thinks of any additional diagnostics please flag them up.

Thanks

 

[Burnerman]

Just a quick check.....
Is the new pump the same as was originally fitted, i.e BFP11L3 or R3?
(Different rotation direction)....I've been caught before when an R3 was sold inside a box marked L3 and I didn't check at that time!
John

 

[spraggo]

Just a quick check.....
Is the new pump the same as was originally fitted, i.e BFP11L3 or R3?
(Different rotation direction)....I've been caught before when an R3 was sold inside a box marked L3 and I didn't check at that time!
John

If,you say that oil spurts out of the bleed hole when the pump is running, this indicates that the pump is rotating in the correct rotation. On the other hand, if the oil was being sucked in at the bleed hole it would indicate that the pump was rotating in the wrong direction.
Therefore you have proved that you have the right pump

 

[bruce3]

Just a quick check.....
Is the new pump the same as was originally fitted, i.e BFP11L3 or R3?

Yep - double double checked and the pumps are identical - both BFP11L3

 

[bruce3]

And an additional but related question . . .

the old controller is a Satronic TF830B which I'm told has been superseded by the TF830.3 which is what has been ordered.

Will the old photocell (for detecting the flame) be compatible and if not any idea which one should be obtained for it? The current photocell is in the form of a small glass vial.

Thanks

 

[spraggo]

And an additional but related question . . .

the old controller is a Satronic TF830B which I'm told has been superseded by the TF830.3 which is what has been ordered.

Will the old photocell (for detecting the flame) be compatible and if not any idea which one should be obtained for it? The current photocell is in the form of a small glass vial.

The correct photocell for the TF830.3 is MZ770S, side on end viewing

 

[bruce3]

Thanks spraggo.

Fitted the new controller and listened for the solenoid with a screwdriver and there was an audible click so I'm discounting the solenoid which implies that the pump is providing negligible pressure.

Still waiting delivery of the replacement pump/motor coupling so fingers crossed that this £1 part will resolve the issue.

 

[bruce3]

I've continued experimenting whilst I await the delivery - and there's a revised observation.

If I remove the pressure monitoring plug from the oil pump (which doubles as the bleed point) it drips.

If I turn on the boiler there is an initial spurt of oil but then that stops.

I know the oil feed to the pump is good and correctly connected - so this would confirm that the pump is not turning?? Which in turn points again to the coupling??

 

[bruce3]

Although I have to say - having just checked the old coupling it sits firm on the oil pump shaft and firm on the motor. It worries me that there might be an air lock somewhere or that the pump has not been fully bled - although I don't see what else I can do to bleed it.

 

[spraggo]

Although I have to say - having just checked the old coupling it sits firm on the oil pump shaft and firm on the motor. It worries me that there might be an air lock somewhere or that the pump has not been fully bled - although I don't see what else I can do to bleed it.

Are you sure that the motor is spinning, or does it just make a buzzing noise, can you feel air being sucked in at the air intake when the motor is running?

 

[bruce3]

Yes - it's blowing air and I also ran it with the pump off to ensure that the spindle is turning - all looks good. Currently checking out the pump in detail. With the pump connected to the oil line and the back off fuel pours in so no obstruction there.

Looking at the construction I reckon that the return outlet port is worth also using as a bleed point for the feed side of the pump so will try that.

 

[spraggo]

With the bleed screw unscrewed can you turn the pump spindle easily by hand and does oil some out of the bleed hole when you do this?

 

[bruce3]

Yes - it turns easily and a little oil comes out of the bleed point/pressure monitoring port. If I replace the bleed screw though and continue turning the spindle nothing comes out of the outlet that runs to the burner nozlel - shouldn't oil exit from there as well?