Wallstar oil boiler locking out

[AlanE]

nixt intermittent solinoid coils quite common problem particually, it seem, on Danfoss pumps

Reset boiler and runs no problem then after varying lengths of time boiler goes to lockout. Replace coil problem solved.

A recognised test, in trade, for these coils is to hold in vice and connect to mains. Insert screwdriver into solinoid, handle down, whereupon magnetic field will hold it in place. Leave for some time and if screwdriver has fallen out coil has intermittent fault.

 

[Nixt]

Yes I know the magnet test and agree with and accept the intermittant coil failure. Its just that I've yet to see it in the field only permanently dead or working coils. No doubt it happens though.

 

[nodiyer]

Thanks for the advice guys but the following have already been replaced:

Atomising nozzle
Non Return valve
BFP coil
Control Box
Baffles
Blast tube

The oil pump has been bled and the system ran to temperature

Its also had a chemical clean.

Any other ideas other than a new boiler!

 

[Nixt]

Within it's lifetime only the blast tube is unusual wear & tear. Control box unluckly but not unlikely. As long as the boiler heat exchanger is sound there is no gain replacing for another.

 

[outinthestix]

Has the motor capacitor been checked ? If this proves ok i would look at the transformer.

 

[Eng33]

Once mine was running it also ran fine, it was only once it sat over night that the pump could not generate the head to flow oil into the pump.

Thanks for the advice guys but the following have already been replaced:

Atomising nozzle
Non Return valve
BFP coil
Control Box
Baffles
Blast tube

The oil pump has been bled and the system ran to temperature

Its also had a chemical clean.

Any other ideas other than a new boiler!

 

[Nixt]

Has the motor capacitor been checked ? If this proves ok i would look at the transformer.

How can this bring the burner to lockout once its sucessfully reached the run phase?

 

[AlanE]

Any other ideas other than a new boiler!

Results from diagnostic check suggested??

Next to check disconnect oil line from pump and do you get a GOOD flow. If not check all filters are clean.

The best way to check oil supply problems is with a vacuum guage fitted to oil pump. If you have one what reading do you get?

And yes pump pressure monitored over say 10 - 15 mins.

Going by your list of items replaced you seem to be confining yourself to guesswork!! Blast tube - what was wrong with it? Baffles - again what was wrong with them. If distorted, or bottom one melted through, then the boiler has probably been run whilst sooted up.

 

[outinthestix]

Who said the motor had reached it's run phase ?

 

[oilman]

Thanks for the advice guys but the following have already been replaced:

Atomising nozzle
Non Return valve
BFP coil
Control Box
Baffles
Blast tube

The oil pump has been bled and the system ran to temperature

Its also had a chemical clean.

Any other ideas other than a new boiler!

Baffles and blast tube were not relevant and were an unnecessary expense. This will be an electrical problem unless it is either the pump or the pump coupling. Time to try a new photocell or transformer, and fit the old ones if this didn't cure the problem.

Otherwise the pump has been know to be the culprit.

Oh, and cracked electrodes.

 

[Nixt]

Who said the motor had reached it's run phase ?

Well now you mention it no-one specifically but when the OP used words like 'fires up' and 'runs for a few minutes' I had this mad idea that it might have passed the ignition/flame detection stage.

 

[outinthestix]

All i am saying is that i have been given information like this in the past but it is not always dead accurate. It's still down to the technician to sus out the problem with whatever info, experience, skills and test instruments they have available and a quick check of the capacitors value would rule it out. Sorry to have caused any offence, none intended.

 

[nodiyer]

Firstly guys I have to mention that I am not a techie (hence the name nodiyer!) all I am trying to do is get suggestions of what might be wrong as the techies I have called out over a 12 month period cannot fix it.

OK, I have done what Nixt suggested yesterday and watched it in operation. The CH had not been on all day. I first checked that the boiler was not in lockout. I then turned the thermostat up to 22. The radiators did not come on. The boiler had locked out immediately. Reset the boiler and it came on fine. There is an air bubble but it seemed to be static. there is oil at both ends of the tube. However when the thermostat was turned to 30 there was movement. Every now and then a bit of the bubble would break off and enter the boiler. I was waiting for this to lock out the boiler but it didn't! I stood watching this thing for over 30 mins and nothing. This then ran for the rest of the day without problem.

If the bubble is the problem and the NRV has been replaced what else needs checking?

I appreciate the help guys.

 

[oilman]

Maybe joints or a leaking pipe, but then you would have fizzy oil. It's possible to bend the feed pipe to the horizontal, then arrange the flexi to give a continuous rise to the pump. But if you kink the copper tube, you're stuffed.

 

[wilhelm]

if it was me, id change the oil pump.

if that dont do it, put old one back on etc.

oh and i would look at the ebi transformer for any bumps etc


that slug of air in pipe is meant to be their.