Any plumbers working today HELP grant reileo 50/70 not igniting

the culture of deference

Any plumbers working today, I dn't want to be without heating with the weather thats coming

Boiler turns on for 5 seconds, then turns off just before ignition,
Over the last month it has turned itself off twice

There is no airlock
Oil is coming through
Rads have no air

bunderoon

the culture of deference wrote: »

Any plumbers working today, I dn't want to be without heating with the weather thats coming

Boiler turns on for 5 seconds, then turns off just before ignition,
Over the last month it has turned itself off twice

There is no airlock
Oil is coming through
Rads have no air

Not a plumber but are you sure that the oil is coming through with a decent rate? Do you have low volume of kerosene in your tank thus producing low pressure? Are you checking at the boiler valve itself?
Have you a stat on the boiler that may be accidentally turned down low -near off setting?

the culture of deference

bunderoon wrote: »

Not a plumber but are you sure that the oil is coming through with a decent rate?

Yes

bunderoon wrote: »

Do you have low volume of kerosene in your tank thus producing low pressure?

No

bunderoon wrote: »

Are you checking at the boiler valve itself?

Yes

bunderoon wrote: »

Have you a stat on the boiler that may be accidentally turned down low -near off setting?

No

bunderoon

the culture of deference wrote: »

Yes



No


Yes

No

Ok. Then I'm out 🙂 One last thing - check your zoned wall stats if you have them. If they are down lower than your house temp, your boiler will turn on alright but will shut down seconds later. Also, dont rule out a faulty room stat. Put your ear to it and see if you hear any little noise. The switch could be dirty and not engaging / making contact correctly.

Good luck with it.

John.G

This won't fix it but will narrow down the failure possibilities, the sequence should be...Fan runs for 12 secs, then the oil solenoid valve is energised (you will hear a distinct "click") and ignition is initiated at the same time, if flame isn't detected in another 5 secs then the boiler shuts down and locks out., the total time is 17 secs.

jimf

if the burner is cutting out before the 12 sec purge time it could well be a faulty control box

also possible room stat or timer issue


does it go to lockout at the burner


how do get it going again after it cuts out

the culture of deference

It is cutting out at 5 seconds just as the oil comes through to be atomized, so I think it could be the photocell but it could be faulty circuit board

the culture of deference

bunderoon wrote: »

Ok. Then I'm out �� One last thing - check your zoned wall stats if you have them. If they are down lower than your house temp, your boiler will turn on alright but will shut down seconds later. Also, dont rule out a faulty room stat. Put your ear to it and see if you hear any little noise. The switch could be dirty and not engaging / making contact correctly.

Good luck with it.

Thanks, it is not the stats

jimf

the culture of deference wrote: »

It is cutting out at 5 seconds just as the oil comes through to be atomized, so I think it could be the photocell but it could be faulty circuit board

if its not going through the 12 sec prepurge and cutting out within that time frame its most likely control box

the culture of deference

It has never had a 12 second purge


it switches on and you hear the pump then within 5 or 6 seconds it ignites

jimf

the culture of deference wrote: »

It has never had a 12 second purge


it switches on and you hear the pump then within 5 or 6 seconds it ignites

what burner exactly is fitted

can yu post a pic

the culture of deference

I got a plumber


It was the capacitor, system back up and running



Thanks for all replies

Wearb

the culture of deference wrote: »

I got a plumber


It was the capacitor, system back up and running



Thanks for all replies

Very unusual behaviour from that burner. If you get a chance please post a pic for future reference for anybody with same problem.

John.G

The capacitor failure isn't unique but IMO the burner firing up after 5 sec is unusual to say the least, hope the phocell etc is doing its monitoring correctly.

Wearb

John.G wrote: »

The capacitor failure isn't unique but IMO the burner firing up after 5 sec is unusual to say the least, hope the phocell etc is doing its monitoring correctly.

A cap that gets the motor going and then can't keep it running is new to me John. But I'm sure i haven't seen it all by a long shot.
As you allude to, there might be something else at play. We all know how difficult multiple faults can be.

John.G

Many years ago I had a grant boiler fitted with a Minor one S burner and it would sometimes run for a few seconds like the above, other times the fan wouldn.t start up.I changed the capacitor from 3.15 uF to 4.0 uF and while it didn't completely cure the problem, it certainly helped so yes it probably wasn't a failed capacitor, I think the fan bearing bushes or whatever they used were slightly binding but overall this particular burner was a bit of a PITA, I couldn,t believe the difference when I bought a boiler with a Riello GX5 burner that has never locked out in 14 years of service.

the culture of deference

I will replace the boiler in the next month, whats todays replacement for the 50/70

jimf

the culture of deference wrote: »

I will replace the boiler in the next month, whats todays replacement for the 50/70

grant vortex 15/26

comes preset at 71000 btu which can be rated up or down

important to get the boiler sized correctly you don't want it oversized as you want it to run in condensing mode for as long as possible

jimf

Wearb wrote: »

A cap that gets the motor going and then can't keep it running is new to me John. But I'm sure i haven't seen it all by a long shot.
As you allude to, there might be something else at play. We all know how difficult multiple faults can be.

ive only ever seen one riello burner do this and it was a very old g3 it would fire up within 6 secs and run perfectly

just to satisfy my own curiosity I switched control boxes to see what would happen prepurge changed from 6 to 12 sec

just switched back boxes again afterwards as boiler was ancient as well

just to add I agree with you john re minor 1 a total pita

DGOBS

Control box is the only item that could cause an early firing (it may actually be a capacitor on the PCB causing this as they can be used for timing)