baxi 105e no hot water

[guest01]

can anyone help last night my hot water was working fine but today no such joy . theres no fault lights coming on the boiler and the central heating works fine just no hot water.

anyone got any ideas ?

 

[namsag]

diaphragm in the change over valve has gone. Bottom left handside of boiler,Housing is brass with a microswitch attached and apprx 3 inches round and faces out ,part costs approx £10 and should not take fitter more than half hour to change.

 

[the trician]

Hi,
I have a similar fault. LED marked 60' flashes when I run the H/W tap and there's no H/W. Book suggests a low pressure or pump fault.

Tried C/H from programmer and C/H fires up no probs.
Call for H/W when C/H is running and burner shuts down. LED 60' begins to flash again. Turned H/W off and burner fires up again. Guage pressure shows around 1-1.5 bar.

Any suggestions?

TT

 

[the trician]

Things have developed! Removed C/W inlet valve and cleaned filter but still no joy.
Checked C/H and DHW microswitches with multimeter - both ok.
Checked for movement of actuating rods (driven by the diaphram) for C/H and DHW, both move full-stroke and are not seized. C/H pump working ok.
Am assuming that if rods are moving, then diaphram is not faulty.

Come on guys - there must be some plumber out there who works on BAXI stuff every day - gizz a hint.....

Pleeezzzze!
TT

TT

 

[duvet77]

Hi guys

I seem to have the same problem as described by the original poster. Running the hot water taps won't fire up the boiler. There's no fault lights and the hot water light doesn't light up. Central heating is working as normal.
It was all working fine 2 days ago, then it just stopped working.

I've already replaced a sensor to solve the a previous problem of intermittent hot water.

Do people agree with the diagnosis by namsag?
I assume it isn't a job for a DIYer? Does anyone know how much it might cost for a repair. I'm going to get a quote but obviously I'd like to be armed with a bit of info.

Thanks

 

[gas_man_gaz]

like namsag said chances are it'll be ya diaphragm thats gone and yes its a easy job for even a diy'er to do

 

[duvet77]

what are the legalities of replacing bits in boilers?
i don't want to do anything naughty or dangerous!

 

[superdupergasman]

not when you are not disturbing any gas components or disrupting anything to do with the combustion.

Changing the DHW diaphram is a nice easy one to do for a starter.

 

[gas_man_gaz]

the part ya need to replace isn't a gas carrying component, ya wnt need to break any case seals and ya wont affect combustion so i wouldn't worry

 

[duvet77]

Right, I've found the following 2 diaphragms on a spare parts site; is it the first one i need?

BAXI DIAPHRAGM (SMALL) COMBI 80E 105E 248065
3 WAY VALVE COMBI 24, 24HE, 30HE, 80E, 105E, 105HE PERFORMA 28, 30HE

BAXI DIAPHRAGM (BIG) COMBI 80E 105E 248066
FOR PRESSURE DIFFERENTIAL VALV COMBI 24, 24HE, 30HE, 80E, 105E, 105HE PERFORMA 28, 30HE

How easy is this job really? will i need to drain the system?

Thanks for your help.

 

[kitch0978]

its the big one for HW......

isolate cold water inlet feed underneath and rear of boiler...open a hot water tap......remove micro switch on front of housing (1 screw).......remove small front pipe going into top of housing( you should get some water flowing through open hot tap at this point but nit much.....undo and remove the 6 ( i think its 6) screws on front of housing...some water will come out of the housing so make sure pcb is protected and u got something underneath boiler too.......ther is a spring behind housing so be carefull....remove old diaphragm and replace in reverse order.........DIY er...20 mins tops......

 

[duvet77]

thanks kitch.
appreciate the help.
that can be my job for this weekend.

 

[bellairaphon]

shouldnt take ya 2 days mate.. stevie wonder could do it quicker

 

[duvet77]

shouldnt take ya 2 days mate.. stevie wonder could do it quicker

lol... I wasn't thinking it would take me two days! just that it's not the sort of thing I can be bothered to do when I get in from work.

 

[TheBoilerMan]

as the diaphragm has cold water pressure on one side and system pressure on the other, can i suggest also isolating the flow and return at the boiler and drain the boiler only. could save a small but wet flood!!