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By zen
Hi due to a leak in diverter valve I bought a diverter valve kit and changed all the components after cleaning out the bloc. I also took off the heat exchanger whilst i was inside the boiler and gave it a complete descale.
when i reassembled everything i seemed to no longer have HOT water in the taps just LUKE warm
if i have heating on first the DHW does start off much hotter then becomes much cooler over time finishing as just luke warm

can't understand how replacing for new the diverter valve components would lose the Hot water where it was previously working fine

ANY HELP GRATEFULLY RECEIVED PLEASE (specific to this boiler would be ideal, or to any combi boiler also very useful)

many thanks for any help you can offer :)
sounds like your descale might have had a reverse effect it may now be blocked!

what boiler and how and what did you descale the p-hex with?
Hi it is a Heatline C28
It was not obviously clogged up (as I have seen in others)
just thought a good clean would keep it going for a few more years - I used a descaler called spirits of salts
looked spotless when finished and all the chambers had been fully rinsed out with water

could it be the TEMPERATURE SENSOR NTC THERMISTER do you think?
its got to be either-
blocked plate heat exchanger
failed dhw temp sensor
by-passing diverter valve
check ntc's with ohm reader, flow switches and connections
you need to test the flow ports in the right holes with p-hex really to proove its good and no scale has shifted to block it.
next, you will be taking diverter apart and re checking assembly is right.

is there heat in the primary flow pipe when hot water is run?
zen wrote:
December 14th, 2019, 10:41 am
Hi Red thanks for your continued assistance
I am waiting for a new temp sensor in todays post

yes there is heat in primary flow pipe

if the temp sensor doesn't sort out the problem I'll work my way through the other tests

thanks again:)
if there is heat on your primary when hot is run, then your diverters collapsed (or not fitted properly)
cant remember it this boiler has a motorised valve, that needs checking for operation, then push pin on dv for flow divergence.

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