Anyone know about oil boilers?
Approx a foot and a half depth of oil in the tank (it runs out of the outlet ok) and boiler fires up, runs for about 20 seconds and then locks out?…
Landlord seems to think oil is too low? Seems odd to me.
What does STW reckon?

Does the burner actually fire?

There’s a photo sensor that needs to see the light from the flame within a time limit, these can get soot on them & need cleaning.

If you plan to move shortly seal the cap. Find the vent…. Glue in a shrader or similar valve. Use a bike pump to positively pressurise tank and fire up boiler. Worked on my folks place to clear a slight blockage (although not entirely sure this is a good idea and probably not good in the long term for boiler)

If you plan to stay, get the oil topped up a bit (maybe not full to save some pennies) and when it still fails then contact LL again

Good luck!

Also just remembered they had an issue with the flame sensor…. This cut off the boiler after about a minute or so. Pretty easy fix

Edit similar to above post!

Or it could be air in the link from a leaking feedline.

Is there any water sat in the bottom of the tank? You can get a build up from condensation over time and as it’s heavier than oil sinks to the bottom and goes out the fuel line, making it mis-fire. You can get some colour change stuff you put on a stick and poke down in the tank to check. If you have a bit you can get sponge type things to put in to soak it up but if there’s loads you may need to drain the tank.

Are you sure it’s actually lighting?

I had a similar issue a couple of years ago where the fan would start, would run for a few seconds and then shut down.

It turned out to be the solenoid which operates the valve for oil into the pump. Best way to easily check the solenoid is to test the resistance of the coil.

Also worth checking the opto sensor which checks that it’s ignited.

Luckily oil boilers seem to be pretty easy things to fix! There’s only about 4 things in ours!

As snaps, photo cell is dodgy. Had similar on our last year.

Simple test would be to find the photo cell on the boiler ( usually easily accessed at the front of the burner with the cover off) and pull it out, its should be a rubberized push fit. Shine a torch in the hole and turn the boiler on, if it fires and runs then dodgy cell, if you have the same cutout problem then probably a fuel level/blockage issue.

IANABT, but this is how I diagnosed our duff cell,  then new one  ordered and replaced and Bob’s your mother’s.

Oh, and I can recommend Abgo for oil boiler spares… I struggled to find anything in any local plumbers merchants and was eventually directed to them. Ordered a part just before Xmas when the motor capacitor died, and it arrived next day. Which was nice as it was chuffing freezing with an unheated house!

Certainly sounds like the optical sensor.
I’d it a riello burner (it will say on the box covering it)?
Pretty easy to work on and plenty on YouTube.

Or tank has been in 18 years and we’ve not had any issue with water.
You may have a blockage though perhaps.

Cheers for the suggestions all, I’d wondered if the flame sensor was likely as it does fire up and burn.
Will hang on for the oil delivery and see if that works and if not see if I can find and clean the sensor.
Doesn’t help the boiler is about 40 years old I don’t think with the worlds most woeful instructions!
Ta!

“the boiler is about 40 years old”

Was there clouds of steam coming out of the flue when it was running?

Oil fired boilers last about 10 years.

The heat exchanger rusts through and you get water leaking into the combustion chamber.

Is there a puddle of water at the bottom of the boiler?

Take the burner out and if water leaks out of the combustion chamber then the boiler has reached the end of its useful life. It will be scrap.

Oil fired boilers last about 10 years.

This is really not true at all. We have a boiler that is also in the region of 40 years old and is pretty rock solid as they’re so incredibly simple (unlike ‘modern’ boilers).

Will hang on for the oil delivery

If you’ve got oil in the tank already then adding more isn’t going to change anything – and you’ve certainly not got 18″ of water in there!

I’d get stuck in and check the sensor now. If it’s a Riello burner (it will say on the box covering it) then there should be a smallish grey box with a big red button at the front of the burner – this is the control unit.

If the red button is lit up (you can see this without removing the cover over the burner) then you’re out of fuel/there’s a blockage.
If you press this button the boiler will try and fire – the blower will come on, then a couple of seconds later the burner should fire … you’ll hear this very clearly.
If the burner fires but then switches off after a little while then it’s probably the optical sensor that’s gone or is dirty.
To clean it you remove a single screw on the side of the grey control box and pull the box off towards you – the sensor is clearly visible as it points in towards the boiler.

If you have run out of oil then the burner/pump will need priming. Message me and I’ll let you know how to do this very quickly (used to take me 30 mins but I can now do it in less than 2).

All this is based on it being a Riello burner.

https://www.boilerguide.co.uk/epc-regulations-2018-changes

Oil fired boilers last about 10 years.

do you sell oil boilers per chance.

thats horse crap.

https://www.boilerguide.co.uk/epc-regulations-2018-changes

So?
An old boiler does not mean the EPC is screwed!

OP, in the picture above the bolt (not the adjustable thing above it) to the left of the control unit is the bleed screw.

Ok, optical sensor pulled out and cleaned. It was quite sooty. It sparks and then emits a merry little plume of smoke from behind where the burner unit is…….

Oil fired boilers last about 10 years.

Ours was 25 years old and still going strong. Serviced regularly, was told it’d happily keep going ad infinitum.

(That said, we’ve just changed it for an external oil boiler – and reclaimed a huge corner of the kitchen floor space by ripping out the old cupboard it sat in. Time will tell as to how clever an idea it was to get rid…)

This is the boiler is that link has worked. Why is that 1/4 turn valve closed? With it open that braided hose leaks oil from 3/4 pin sized holes. Think it’s that?

10 years is pretty good IMO. My Worcester Bosch boiler lasted 7 years before it self destructed and spewed noxious gas through the house. TBH, if you know nothing about boilers, then I suggest calling someone who does.

No idea what I did but it seems to be firing and running fine now! Off out for an hour so assuming the house hasn’t burnt down on my return that seems to be a success.
Thanks All!

Ours was 25 years old and still going strong. Serviced regularly, was told it’d happily keep going ad infinitum.

(That said, we’ve just changed it for an external oil boiler – and reclaimed a huge corner of the kitchen floor space by ripping out the old cupboard it sat in. Time will tell as to how clever an idea it was to get rid…)

Did the same – and some old boy gave me 200 quid for the old one because “they just dont make em like that anymore”

REplaced it with a grant which has been going for 10 years now. I should probably save for its imminant expiry.

“No idea what I did but it seems to be firing and running fine now!”

Good, I’d always check for soot on the photo sensor or spark electrodes first & don’t open the oil pipework unless your sure its the cause as you could get air in the fuel giving you an extra cause of poor running.

Your landlord’s strategy of not giving a **** is certainly bearing fruit 🙂

Having had an oil fired boiler for 15 years now (and i think it’s pushing 30
years old now), I’d echo some of the above:

Old boilers go on and on (new ones don’t, according to the guy that services ours)
They’re pretty simple things
Assuming fuel isn’t contaminated with water
Then if it’s doing “something” for a bit but then cutting out it’s likely to be one of these:

Failed solenoid (acts as a deadlock/cutoff to the fuel)
Failed/failing motor
Dirty/failed photo sensor
Blocked/damaged nozzle

We’ve had all of those happen and in all cases it will still try to start (make some noise) before cutting out.

(Edit: just spotted it was the photo sensor)