Oil Boiler constantly locking out

[Martin O]

I have an oil fired Grant Boiler, it is constantly locking out, there is plenty of oil in the tank, it has been bled through several times but air is constantly getting into the line causing it to lock out.


It has an old steel tank which has a plastic tube fuel level gauge, what I have noticed is that when the boiler fires and runs ( It can run for 2 minutes or an hour) the fuel from the gauge is emptied and drawn back into the tank, when the boiler locks out the oil fills back into the gauge but with air bubbles in it, also when the boiler is running is sounds like someone is having a bath in the oil tank the oil is swirling and lapping against the sides... is this normal ? Can it be pulling air in or is it possible all the oil movement is creating air in the tank.

 

[Chalked]

Have you pressed the green button on the gauge.?
try it to see a true level.

 

[Killy Bing]

Your engineer will have some sport with this one but a competent engineer could sort it

 

[Martin O]

Hi, there is no button on it (its very old), but when the boiler is not in use it does rise to the correct level.

Already had an engineer out, he was not much use, changed injector and photo cell but did'nt solve the problem. Should oil be swirling around in the tank when the boiler is in use, is this normal ?

 

[Best]

Is there one oil pipe from oil tank - or two?

 

[Martin O]

Just one

 

[lame plumber]

sounds like youll be needing a new pump soon, check tank level first via the inlet or inspection flap

 

[tamz]

Sounds like it is a 2 pipe right back to the tank. Get someone better in to look at it than whoever has been at it recently.

 

[Martin O]

Got somebody else coming out but he can't get to me till Christmas eve.

 

[Bunker]

Tell us more about the set up at the tank, take a photo if poss. You will need an engineer though, check the OFTEC website for a local registered chap.

 

[kimbo]

Is the boilet graviyy fed or is the tank below the level of the boiler.

 

[MarkOil]

Tank valve is possibly blocked, probably a valve with a tiny grubscrew, then the on/off wheelhead underneath, the the sightube, then filter, then off to boiler.
turn off tiny grub screw remove and clean valve, job done.
Could be that anyway.

 

[SimonG]

When was it last serviced? Was the oil filter changed?

 

[lame plumber]

Tank valve is possibly blocked, probably a valve with a tiny grubscrew, then the on/off wheelhead underneath, the the sightube, then filter, then off to boiler.
turn off tiny grub screw remove and clean valve, job done.
Could be that anyway.

this could be a good or a bad ending pictures needed of tank valve first would be my reccommendation

 

[Martin O]

Thanks for all the replies, I finally solved the problem today (I hope), as I mentioned in my earlier post the oil in sight gauge tube for the oil level was drawn back into the tank when the boiler was in use, then when it locked out it would refill with oil and air bubbles in it. The tube is fitted into the tank valve so I guessed that if bubbles were coming out they must also be going in. Got rid of the tube and capped it off. Boiler has been running all day with no lock outs so fingers crossed.