Sabre 29he boiler problems

[Piperdave22]

for some reason my other post has been deleted :s

Sabre 29he Combi , originally customer said it was clicking on and off on hot water so thought it was heat plate blocked causing it to reach temp to quick and cut out so I have changed heatplate and changed divertor at the same time but not the head. After I got parts he said it was doing it on heating aswell
After I fitted parts I stayed there for 15 mins and all was working fine got him to check everything and he was more than happy .
But that evening it went back to what it was doing originally and it’s locked to solid red light in manual it says NTC open /short circuit so have ordered both ntc sensors and going to replace them but any advice from anyone that’s worked on these would be appreciated please!

 

[Piperdave22]

Would you be able to help at all? Have a video if that helps

@king of pipes, @Harvest Fields, @ShaunCorbs,

 

[ShaunCorbs]

Post the vid up if you can

 

[Harvest Fields]

Not at home yet mate. If I remember I will.

 

[Piperdave22]

It’s had a heatplate,divertor,ntc sensors and overheat stat fitted. It’s a lot better than it was but seems on heating it does this intermittently but once fired will stay on till it reaches temp etc sometimes it will fire straight away though.
My thoughts are the pcb but obviously it’s an expensive part to try if it still doesn’t work after.

 

[Harvest Fields]

Did you check to see if the power was dropping from the board to the gas valve when trying to light?

 

[Harvest Fields]

Is the standard 29he or he plus? And does it have 1 pcb or 2?

 

[Harvest Fields]

Looking at the manual now these also had a issue with the condense wasting away.

 

[Piperdave22]

Have uploaded a pic it has two pcbs pretty sure it’s the 29he not the plus number 19 and 20 in pic
Haven’t checked the pcbs yet no
And do you have any more info about the condense problem?

 

[Harvest Fields]

Does it keep sparking when the flame dies?

 

[Piperdave22]

At 14 secs and 32 secs on the video if you turn volume right up you can here it sparking .
When it cuts out it just constantly tries to relight until it’s lights up then it will stay on till it’s reached temp etc

 

[Gas74]

Remove one of the tubes off of the aps. That may well fix it.

 

[ShaunCorbs]

Gas valve def letting gas through when it sparks ?

 

[Harvest Fields]

Gas valve def letting gas through when it sparks ?

It looks like it is letting some through then switching off but he said it continues sparking. Board or valve for me. But without being there that’s not 100% mate.

 

[Harvest Fields]

I would check the power at the board and gas valve when sparking. Also check all your gas pressures as @ShaunCorbs said

 

[Piperdave22]

Remove one of the tubes off of the aps. That may well fix it.

Surely these have to stay connected? Are you suggesting a faulty aps?

 

[Piperdave22]

I would check the power at the board and gas valve when sparking. Also check all your gas pressures as @ShaunCorbs said

Yeah that’s not a bad shout as I’ll be able see it drop on manometer if letting gas through .
What points do I test on pcb?

 

[ShaunCorbs]

4 and 5 on the gas valve looks like it's 230v maybe

 

[Harvest Fields]

Look at CN5 on pcb there is only two wires mate. Brown and Blue

 

[Harvest Fields]

4 and 5 on the gas valve looks like it's 230v maybe

Sorry mate replied before reading all the posts.

 

[mfgs]

Most problems on these boilers are a blocked venturi on the fan, the primary NTC or the pcb. If its cycling really bad, also check the pump and main heat exchanger for blockages.

 

[Piperdave22]

Pretty sure it’s not pump or heat exchanger as still doing what it’s meant to be sometimes struggling sort of intermittent.
Have blown out aps tubes didn’t seem to make any difference .
It locked out on red once and it said ntc in manual so have replaced ntc sensors
I’m going to test pcb / gas valve and ring vokera tomorrow and see what they suggest .
Will keep you updated

 

[ShaunCorbs]

make sure its before 10am as they leave early

 

[Piperdave22]

Just spoke to a guy that’s pretty much asleep on the phone lol.
He said to try taking the fan out completely cleaning the fan and Venturi . Check there’s no flue blockages , check main heat exchanger and condense heat exchanger?

 

[Piperdave22]

I have spoke to vokera repairs and they charge £285 inc vat fixed price repair. Covering up to £450
Looking for advice is it worth me going to take the fan out and cleaning out the Venturi, condense heat exhanger .
Or is it mostly likely to be gas valve pcb related?
It’s for a friend so it will be cheaper to get vokera out if it’s a case of gas valve or pcb.. with parts and labour etc and not being 100 percent don’t want to rip him off .

 

[Harvest Fields]

If it is for a friend or family member I would be more inclined to tell them to fit a new boiler. £450.00 for a Vokera call out(max) could go towards a a new one and to be fair there is nothing to say once it is fixed it will not break again in 4 months. (Just an idea)

 

[mfgs]

I have spoke to vokera repairs and they charge £285 inc vat fixed price repair. Covering up to £450
Looking for advice is it worth me going to take the fan out and cleaning out the Venturi, condense heat exhanger .
Or is it mostly likely to be gas valve pcb related?
It’s for a friend so it will be cheaper to get vokera out if it’s a case of gas valve or pcb.. with parts and labour etc and not being 100 percent don’t want to rip him off .

Venturi fault doesn't always cause it to lock out. It just the fan keeps running or it drops out and struggles to start again. Obviously not getting to sparking stage as the APS wont operate. Normally with a partially blocked venture removing the combustion box door will allow it to light with the increased air flow.
PCB fault just causes completely random solid red lock out with no real pattern from my experience. I always start with primary NTC which you have always changed and then move to pcb as they are expensive!
Ive never had to replace a gas valve on these, and I have worked on a lot of them. Used to look after about 40 of them, each one has had a blocked venturi at some point.

 

[Piperdave22]

If it is for a friend or family member I would be more inclined to tell them to fit a new boiler. £450.00 for a Vokera call out(max) could go towards a a new one and to be fair there is nothing to say once it is fixed it will not break again in 4 months. (Just an idea)

I have already advised this as soon as I saw the boiler but they wanted to try and repair , they said it’s a max of £285 the customer will have to pay unless bill goes over £450 then they may have to pay a bit extra but will always let them know.

 

[Piperdave22]

Venturi fault doesn't always cause it to lock out. It just the fan keeps running or it drops out and struggles to start again. Obviously not getting to sparking stage as the APS wont operate. Normally with a partially blocked venture removing the combustion box door will allow it to light with the increased air flow.
PCB fault just causes completely random solid red lock out with no real pattern from my experience. I always start with primary NTC which you have always changed and then move to pcb as they are expensive!
Ive never had to replace a gas valve on these, and I have worked on a lot of them. Used to look after about 40 of them, each one has had a blocked venturi at some point.

It is randomly dropping out and struggling to start again (see vid above ) but is also sparking . Would it be worth taking out fan and cleaning Venturi?

 

[mfgs]

If its sparking, then it wont be a venturi fault as its getting past the APS stage of the ignition. Check the gas valve is opening, if not check for voltage from the board.

 

[Harvest Fields]

If its sparking, then it wont be a venturi fault as its getting past the APS stage of the ignition. Check the gas valve is opening, if not check for voltage from the board.

Said that above mate

 

[mfgs]

Said that above mate

I said it above too

 

[Harvest Fields]

I said it above too

I know.

 

[king of pipes]

Late to the party but as above gas valve first check , pcb ouch. Kop

 

[Harvest Fields]

Late to the party but as above gas valve first check , pcb ouch. Kop

That’s why I said new boiler as I remember pricey.