Baxi 105e Instant - Noisy Diverter Valve Operating Head

21 Oct 2004
Reaction score
United Kingdom
Diverter valve operating head makes a vibrating noise when on CH mode. Is ok from cold, but noise appears after a few minutes of system warming up. If you press lightly on the top of the diverter head the noise quietens down. Anyone know of a cure other than replacing the operating head.
Also by restricting either the flow or returns from the boiler by closing valves slightly, stops the noise altogether.
Thanks :confused:
Sponsored Links
its not the operating head thats causing the noise, its the o-ring inside the valve. you need to get the valve changed, these can be quite tricky, and i wouldnt recomend you do it your self.

closing the valves could cause you to overheat the boiler as it restricts the flow of water through the heat exchanger.

if boiler is still in warranty phone heateam ( ) they are the service devision of potterton, if your boiler is just out of warranty, they might still take it on.

if not, heateam charge about 170 quid.......
I've heard of noises coming from these many times but never come across one. Jason has the design changed or is it just so much effort that you might as well change the whole valve, or...?

105's had a problem where the divertor valves had an o-ring in which was prone to swelling, causing a screeching sound, this can also be caused by dirt, but normaly its the o-ring.

the new divertor valves have a new type of o-ring.

it is possible to change the ring itself, but have never changed one, have always changed the valve as customers pay a set repair charge, and dont pay for parts and its cheaper from a company point of view to just replace the valve.

its one of those jobs you always cop for on a friday at 4 oclock.......... :oops:
Sponsored Links
Thanks m8, I'll get myself a spare then.
I see the non Instant is a different part no for the diverter. Does that have the same trubble?
jason do you work for baxi jf so just want to pick your brains
work for heateam, (you know, the one all you installers love)

am still quite new to this game though, but fire away with you questions.......
Well the first one's there, do the non "Instant" combis suffer with the same noises - I not the DV is a different part no. ?
yes, they have different divertor valves, the instant, is a bit more difficult to change, as you have to drain the store..

normaly its a screeching sound, but somtimes its a sort of squeek when you turn off the dhw tap.
Can some one tell me how to drain the store ? and what parts are required to sort the exact problem ? i hear that you can get an 'o' ring for it rather than renewing ?#

pictures would be helpfull ! if available


DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links