Baxi Bahama Combi Boiler not completing cycle

[emanc73]

Hello everyone, I know this probably happens all the time but I’m in need of some help and advice. My Baxi Bahama combi boiler has a intermittent fault. It won’t always completing a cycle on either the heating or cold water. I had a friend of a friend come round who works for BG to have a look at it for me. He advised me that the flow switches were at fault on both the hot water and heating. He gave me a price of £80 to replace both switches. £40 for the switches (£20 each) and £40 to fit to which I agreed. Unfortunately this hasn’t cured the problem.

I’ve since had him back to take another look and of course the boiler worked perfectly.

I explained to him what was happening and he now thinks the Air Pressure switch is at fault.

So having replaced the flow switches at a cost of £80 it now looks like it’s gonna cost more money to have the pressure switch replaced.
My question to anybody which maybe able to help me is, how much will I be looking at to replace the pressure switch? and do you think the diagnosis of a failing pressure switch is correct?

Thank you in advance for taking the time to post.

 

[spacethegas]

It won’t always completing a cycle on either the heating or cold water

please expand.

 

[twgas]

is it completely dead....

does fan run....

does pump run....

is it sparking....

or anything else

 

[emanc73]

No it’s not dead. I can here the fan start, but no click then boom as the gas ignites if that makes sense. Does this on both the heating and water.

 

[emanc73]

Sorry I forgot to say, I have to press the reset switch on the front to get the boiler to ignite.

You can hear the click and boom as the gas lights.

 

[spacethegas]

it may well be an aps or venturi problem.

 

[twgas]

might be APS, but then it might not be.

is there a spark but no gas, or is there gas but no spark or neither.

 

[emanc73]

What’s an APS?
Couldn’t tell you if there’s a spark but no gas, or if there’s gas but no spark.
I will attempt to find out now.

 

[emanc73]

Boiler running fine at the moment. In this order spark, pilot light, gas.

 

[emanc73]

Ha ha just realized what you guys meant by APS.
I might have him change both the APS and fan venturi pipe.

 

[spacethegas]

don't get too carried away yet.

 

[emanc73]

Typical, boiler running ok now can’t replicate the fault, will try again tomorrow. Thanks for your replies, your helps appreciated. Please check back tomorrow evening. Ian

 

[baxpoti]

More likely to be a gas valve problem.

 

[emanc73]

Evening chaps, good news of sorts.

I’ve just had the boiler running on the CH for the last 15 minutes while observing each cycle through the small observation window.

This is what happened, the fan begins to run on problem but after that nothing happens, NO SPARKS to light the pilot thus not igniting the burners. If I then press the reset switch while still looking through the window almost immediately there’s a spark and it completes it’s cycle igniting the burners.

Does anyone have an idea what might be causing this fault.

Thanks

Ian

 

[emanc73]

bump