Baxi 105e diverter valve refurb

[Lee Hough]

Hi All

I have ordered a diverter valve repair kit and will be attempting this install tomorrow. I have successfully repaired the diverter valve front diaphragm last year. The arrow on the diagram indicates the current issue, the push rod does not move up and down successfully if pushed down then the dhw works for a while and then stops 24hrs later until pushed back down. What is this part called? and i'm assuming that once i take the whole thing out, i can follow the same process for the front diaphragm repair, removing the screws to gain access to the other push rod. Does anyone have an exploded view of that section to assist me?

 

[Hot&Cold]

What is this part called? and i'm assuming that once i take the whole thing out,

The arrow is pointing to a gland nut seal,the part below is the central heating pressure diff valve-sometimes called main flow switch.

No need to take the whole thing out,most repair jobs can be done with the valve in situ. Try not to make the job hard-work . First approach is to replace the diaphragm, gland nut & grease the push rod spindle in the pressure diff valve and see how it works afterwards.When were these parts last exchanged ?.
https://www.nationalboilerparts.co....ow-switch-diaphragm-repair-kit-plate-5111141/

Other work may be required but changing the above is straight forward,the manufactures installation servicing instructions will have limited exploded views. There is usually some videos

This guy has exchanged the complete valve probably a good idea as its sludged up at 3.40 he starts taking the pressure diff diaphragm out.

Happy fiddling

 

[Lee Hough]

That's brilliant thanks for your help I must have stuck gold my first post and such a great reply

The only part I have replaced is the main diverter valve diaphragm and push rod on the front to my knowledge the rest of the diverter valve is as was so 10 years old I think

 

[ianmcd]

you have been given good advice , doesnt matter the age of the valve is not important, its just a brass casting, just service it

 

[Lee Hough]

Update post two weeks on

I followed the advice and only took the back piece off without having to remove the whole thing here are some photos of what i did hopefully to help others in the future.

1st the issue for me on the diverter valve their are two moving elements the first at the front is to understand that you have turned the tap on and a push pin moves out to trigger the micro switch this was working fine for me, the second push rod at the back moves up to i think tell the boiler it has enough pressure or its below temperature and therefore allow it to ignite the gas. For me this pin was sticking in the midway up point not going down when no demand was requesting heat and also not moving up when required. point 1 is the where the pin should move up and down.

First thing i did was to drain down the boiler over on the right hand side there is a black hose connector hook a hose up to 2 and then turn the drain stop 3 in the below photos.

Once drained remove the micro switch by removing the screw 4 in the photo below the switch will then come away as in the second photo I left mine attached until I had removed the cover as it was a bit seized but I think getting this out of the way first would make the job easier

Now remove the pipe at the rear of the diverter valve using a spanner located at point 5 below

Undo the four screws on the top of the diverter valve point 6 the valve top will then come off

watch out that everything comes with it the photo below shows what should come out the diaphragm on the right may be stuck in the housing and needs gently lifting out

The inside of the valve was dirty so i cleaned this up to remove the black from it i then did the reverse and refitted with new components that i purchased form ebay. I purchased the whole kit that includes new brass components and all the springs and everything required. But i only replaced these components and it fixed my problem i may have just been able to clean it up and re lubricate the push pin to have gotten it working. I Took my time and in total with lots of tea it was about an hour and a half to do i would imagine a professional could do this job in under 30 mins.

 

[Markm49uk]

Great post. For most thing the 105he is a simple boiler to work on - with the exception of the expansion vessel..

 

[ianmcd]

Good post for Diy, but trust me folks, if you are going to do this make sure the pcb housing is completely covered with either a poly bag or a towel, or even better both, you dont want any water getting in there , one of the worst boilers for it

 

[Peterpies]

Lee, brilliant post I’ve just followed your example and cured a problem umpteen people have commented on and none were able to provide a real answer to apart from throw more money and parts at it, which is not a fix but a mere hope and guess approach, which I find very hard to go along with. Was a little tight for room in getting the screws undone but when accomplished found that pin and diaphragm needed attention when complete put back together, hey presto all works. Thank you so much for your engineering approach really appreciated