Baxi Bahama 100 Combi Boiler

[ekkypoo]

I have one of those POS Baxi Bahama 100 boilers. It was working fine until a few weeks ago when I turned off the CH as the weather was ok. A few weeks later I turned it back on but when trying to run CH the boiler fires for about 30 seconds then cuts out for a few minutes, then fires again for 30 seconds and continues this cycle. I have noticed it now getting noisy, (sounds like clicks and whooshing). A couple of radiators near the boiler (kitchen and hall) get quite hot, a couple of others get
lukewarm and most upstairs do not get any heat at all.

The hot water is running completely ok, so am a bit stumped. Don't say CH flow switch as I have shorted (for diagnostic purposes only!!!) and this makes no difference.

Any help much appreciated.


Cheers


Andy Burke
Middlesbrough UK

 

[weargas]

sounds like a diverter valve problem. Have a look at the little white indicator on the right hand side of the diverter valve. It moves back or forwards depending on what mode the boiler is in. i can't remember which way is which mode but you should see a change when you turn on?off a hot tap. replacement is a POP, push the little alloy button, twist anti 1/8th and pull forwards. (unclip electrics as well)

 

[meldrew's_mate]

At risk of stating the bleeding obvious have you checked the system pressure is above half a bar, and usually 1 bar?

Topping up will then restore operation (after bleeding upstairs rads top-up again) but you must then complete the job by finding and curing the loss of fluid (leak or discharge of water) which caused the pressure to drop.

Once that's done add corrosion inhibitor for long term protection.

 

[ekkypoo]

Cheers for the replies. System pressure is ok, all radiators are bled. I am running some sentinal sludge remover at present and will drain/refill the system at the weekend and check the diverter valve. (something I half suspected but will now go down this route first). Is it worth removing the pump and valve and manually cleaning or is it a case of once they're gone they're gone?

Andy

 

[gazthepottertonengineer]

i hate to say it but it could be that pump has got muck in it and its not circulating the heating fast enough

 

[ekkypoo]

Right, another job for the weekend. Strip down the pump!

 

[Mikeyboy]

Two things possibly the problem.There should be a steel mesh filter installed above boiler isolating valves.Can:t remember if flow or return,check manual.This must be clear.Also the three port valve is fitted with an internal honeywell plastic cartridge.These are well known to become jammed or broken, even though the valve motor is operational.Easy job to replace cartridge,just be sure you do not leave broken pieces within recess.Just remembered,one more thing, ensure auto air valve at top of boiler is operational when re-pressurising boiler.Good luck.

 

[ekkypoo]

Diverter valve electronics box working ok. The lever on the side is normally toward the front of the boiler. When you switch on DHW the lever moves away from you. How stiff should the valve be. When I move it back and forth manually it seems very stiff.

Pump may need a clean but are there any more suggestions before I drain the system to clean pump and CH flow filter.

One more thing, does anyone know where to get a new copy of the installation and maintenance guides and the user guides. I have put them somewhere and now cannot find them. I think they may have gone out with the recycling(probably where this boiler belongs!!!!)

Cheers

Andy

 

[ekkypoo]

Just been on Baxi website, all manuals, data sheets, installation instructions now on there. They've done something right........

 

[ABYS369]

I think your problem may be the metal filter in the C/H return pipe is blocked, if you close all the valves on the boiler and remove the C/H return pipe the filter is situated in the pipe, it's prudent to replace the fiber washer.
AB.

 

[ekkypoo]

Thanks for that, I am draining the system this weekend and thouroughly cleaning the lot. Cheers for all of your replies

 

[ekkypoo]

Memories of summers past, that warm glow with a first kiss...... Hang on the reason I feel so toasty is that I fixed my boiler, positively tropical in the whole house now. Even the bathroom radiator which has never worked in the four years we have been in the house is, well, radiant!!! Drained the system and cleaned the CH filter and pump which were both absolutely chock full if rubbish.

Thanks for all the replies.

Cheers

Andy