Ravenheat csi85 combi DHW problem

[ambi]

Hi all,
Dads heating system playing up,would appreciate any pointers/help.
D/H/W does not heat or boiler fire at all when called for alone. But if Hall/wall thermostat calls for C/H it can give hot water, but only when heating in operation ( even on a hot summers day he has just told me). Ravenheat combi Csi85 model.

 

[clf-gas]

Will be the diaphragm within the threeway valve.
Quite easy to repair DIY.

 

[ambi]

cheers clf-gas,
That was a quick confident reply........Just split apart then and put new diaphram in?

 

[clf-gas]

No, you need to isolate the water first

Im sure its detailed in here, though I aint read it.

Full instructions http://www.ravenheat.co.uk/pdf/manuals/CSI85A(T).pdf

 

[ambi]

Sure, appreciate that.......close flow and return to boiler, open hot water tap to drain down boiler and release pressure, then split D/V....Is it just a straight in with new one., and refill /pressurise........What I meant was you seemed pretty confident that would be the fault?
Regards

 

[clf-gas]

Yes, but turn of cold water supply to boiler as you are working on this side of DV.

Yes I am confident, Its what I do for a living , and a good one at that

 

[ambi]

Copy that!
That`s what I like.........................cool man!! This is also in Lancs...Maybe I should check also that the pin is not making the switch first ...What do you think? Local suppliers will have diaphram?

 

[clf-gas]

Definately the diaphragm then.

To prove turn on a hot tap and manually activate the pin, hey presto, hot water'

Yes, local parts suplier will have one in

Where in our butiful county are you

 

[ambi]

Definately the diaphragm then.

To prove turn on a hot tap and manually activate the pin, hey presto, hot water'

Yes, local parts suplier will have one in

Where in our butiful county are you

I thought maybe it would be agood idea to check if pin is moving/making on d/v first.What you think?
Manually activate .you mean pull it out towards switch? or overide?

H/Bank.........Near Preston
Cheers for input

 

[ambi]

clf-gas,
Many thanks for your info........I think you are going to be spot on with your diagnosis. I have checked supplier for stockage of diaphram. Excuse my going over again, but prior to purchasing said part. If you went to this problem, what would be the checks/tests you would look at or do prior to concluding the diaphram as the culprit.
What usually is the problem with the diaphram?. Can it be removed and cleaned of scale etc and put back?
Regards

 

[ambi]

Thought it would be nice to report back..............
Unable to test diaphram by activating pin as boiler will fire but the primary circuit to heat dhw does not circulate......Decided it was a good odds bet though and went for diaphram change...........Upon removal old one was torn and perished and new one fitted........Now all tickety boo and A1.....Like a new one and hot across all fronts when called for. Dad can get a nice bath now....
Thanks for your input and advice...........nice one