Ravenheat csi 85 combi dhw

[mazperks]

Hi,
parents rang me saying they have hot heating but only warm water when tap opened.
I thought its probably dirty hex and went round, but found dhw will only fire up if heating is running. Also nothing if selector knob is on dhw only.
Is this more likely to be a diverter problem?
Thanks for any input Ian.

 

[Agile]

Most likely to be a DHW flow sensor problem!

Probably a holed diaphragm.

Tony

 

[mazperks]

Thanks for that Tony, I'll dig out the manual and find it.
Is it easily spotted.

 

[mazperks]

I've located the Low water pressure sw, ( large black gizmo with 3 terminals ) is this the one you referred to,
or were you talking about within the diverter?

 

[Agile]

No.

The flow is sensed by a hydraulic diaphragm unit fitted at one end of the diverter valve. It operates a switch on one side and retracts a pin on the other which enables the diverter valve inside to move to follow it.

Tony

 

[mazperks]

Thanks again Tony,
I found a diagram of diverter flow, see exactly what you mean.
Ian.