Parva He M96 problem - no hot water or heating

[munchie63]

Hi all, having a problem with a 5yr old Parva He boiler.

It's been fine until 4 weeks ago, when we woke to find no hot water. switched dial off, turned on again and hot water came back on. same thing happened following day.
Booked local firm out for service, which was done, and after they removed the cover and tested the boiler, the heating and water kicked back in. Worked fine for 3 weeks, until Weds when it stopped again.

The error lights are flashing lights 1 and 2, with light 3 staying lit - manual shows it as Frost Warning error ?

the local plumbers said that fan was working, but boiler didn't seem to be firing up to heat water etc. Probably a safety cut-out issue and replaced the gas pressure switch on Thursday. Worked fin Thurs and Friday but same fault since yesterday, although we had hot water for about 30mins last night. This morning nothing, and same warning lights.

so far I'm down £205 plus the service bill and the hot water still seems to work when it likes.
any suggestions / advice appreciated folks

 

[Agile]

There is n gas pressure switch!

That fault code would indicate a faulty NTC sensor.

I think you need a better engineer who does not overcharge you.

Tony

 

[munchie63]

There is n gas pressure switch!

That fault code would indicate a faulty NTC sensor.

I think you need a better engineer who does not overcharge you.

Tony

Hi Tony, they suggested that as the fan was running it was the ignition not kicking in due to a safety switch ?
part label says huba flue gas pressure switch kit

 

[Agile]

There is a part generally called an air pressure switch ( APS ). Although as that's associated with gas/combustion which we don't advise about on here to DIYers.

If the boiler indicates a temperature sensor fault then that is what would usually be investigated first.

Obviously, to me, replacing that APS has not cured the fault!

Replacing parts without having properly diagnosed the fault indicates an engineer without proper diagnostic skills.

The APS can be tested as a component ( although few do that ).

Tony

 

[munchie63]

local firm returned again on Monday as no hot water or heating again. Same problem as before.....doesn't ignite. fan seems to be running. Engineer removed the fan and gave it a good clean, refitted it, and hey presto, water came straight back on again. That was Monday about 5pm. Shower and taps worked fine for 48hrs, until 7pm tonight, when I turned the kitchen tap on and found no hot water again.

Pressure ahs been staying steady at just over 1 bar (would normally be on 1.5 but didn't want to top up incase it raised a little anyway when the heating came on), waters been nice and hot and temp dial on Biasi was showing 40-50.

The fella who came Mon was an older guy, seemed very nice and experienced, and quickly got the part out, cleaned and replaced. Didn't charge me, although having paid for the APS I hoped not.

Big question now is to I call them back or go for a different local firm ?
With the left hand green light and middle red light flashing together manual shows frost protection error. Fella Mon said 9 times out of 10 failing to ignite was either APS or fan problem. Said fan possibly running slightly slow and not enough to kick the ignition into thinking its on. Any way to know though ? Replacing the fan wont be cheap esp if its not the issue. Could it simply be a faulty ignition switch ?
feel a bit like I'm risking throwing good money after bad, but with 2 kids need heat and hot water.

In Upminster, Essex BTW.

Any sound advice appreciated

 

[Agile]

You should update your profile to show your location.

A competent engineer will do several tests to ensure the boiler is working properly.

He will use a digital manometer to measure the pressure presented to the APS.

He will use his digital laser tachometer to measure the fan speed.

But none of your engineers have apparently investigated the frost protection fault code. You could do that yourself if you have a digital multimeter.

Tony