Oil boiler lockout - air in line?

[Jakg]

Noticed I have no hot water and the boiler wasn't firing up, lockout light was on, pressed the button and it came on for a bit before going off again.

Had a closer look and noticed the clear final bit of the oil supply line was empty.

Tank claims to be half full (metal and can't see inside) so tried bleeding the oil pump with the bleed nipple and got the supply line full of oil and it seemed to fire up ok, but when the nipples closed, it just fills with air and cuts out and you can see the bubbles coming up from the tank side of the line into the clear bit.

From a quick look online I'm guessing I've got a bad seal or something and the pump is pulling the air in that way instead of oil?

I've got a service booked in two weeks time which I guess needs to become a repair, but I'm reasonably handy (not that you'd get that from my description so far!) and am happy to have a go if it's something DIYable...

Boiler is an HRM Wallstar 20/25 (2003 I think).
The oil tank is probably original to the house (late 80's...)

Any thoughts?

 

[Cozza]

Hey Jacg,

I'm in the same boat now for over a year, but too tight to pay for a service engineer again. Last time he took 2 days to fiddle with it and ended up replacing the motor, but left the capacitor hanging down with exposed terminals (Ouch!) as it wouldn't fit otherwise.

Our boiler trips 2 or 3 times a day, I think the motor capacitor is faulty as sometimes it just hums instead of running when the orange light is pressed; press it again and it runs. But I had your problem about 8 months ago; have you checked the tank outlet filter isn't blocked?
Also, can you rap with your knuckles to estimate where the oil level is, in case you've got a faulty reading?

Hope this helps, hang in there!

 

[Johntheo5]

Can you disconnect the oil line at the pump inlet and measure the amount that flows freely into a container, should be at least 55ml after 1 minute.
Also ensure oil tank air vent clear.

 

[Jakg]

Can you disconnect the oil line at the pump inlet and measure the amount that flows freely into a container, should be at least 55ml after 1 minute.
Also ensure oil tank air vent clear.

What do you mean by tank vent, please?

 

[Johntheo5]

That's the green item sticking out on the tank top, unlikely to be blocked but you can unscrew it to check and also confirm oil level in the tank. You could also (before doing this) remove the blank plug from the oil filling line and see if boiler continues to fire, have you checked the oil flow?.

 

[Jakg]

So embarrassingly it looks like I have no oil.

The sight was full and there was some when bleeding it, but when I put some fishing rods in only the very tip was wet. And for a tank that's meant to be 80% full, the level looked very very low.