yep that should do it
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now I’m confused there are two PRV. One ch and one dhw. Which one do I need based on fact it overflowing and there’s no ch demand switched on?!
assume dhw is blue cap, ch grey cap
Grey cap
So the blue dhw wouldn’t be passing also? I’ll order and replace the grey
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the blue one would have no affect on your boilers primary pressure in any way
think I have the PRV today? Should I drain like you showed me other night?
also my boiler has a small 1litre expansion vessel underneath the main one - does this need pressurising as well?
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If you are changing the PRV you can just use the existing one to drain the boiler or use the drain point doesnt matter as long as whatever you use is left open as you pressurise the EV, the small ev will be for the cold water inlet you shoudnt need to touch it
Thanks @ianmcd
with the pressure rising overnight after charging the EV, is that down to the PRV again or is there something else I need to be considering? Cold water pressure here is quite high so maybe I need to down mains pressure down?
if the pressure rises with the silver hose disconnected it will be your plate heat exchanger
Hi @ianmcd
PRV arrived today and just fitted it. The vent pipe outside is still dribbling water when I’ve set everything.
steps I followed : released system pressure, replaced PRV, leaving drain valve open repressurised the EV to 0.9bar. Closed drain valve.
opened cold inlet main feed. Opened filling loop inlet, then opened return valve to bring system pressure to 1.2bar. Closed return filling loop valve then inlet filling valve.
boiler on, hot water demand. Did get a fan error - is that cause the pipe work is empty for example? Any ideas do I need a procedure to get system going again?
think I didn’t set it all right after drain, got a fault code “too much air in system” - ?!
either way, still getting that venting dribble, take it only option is the heatx now?
PRV arrived today and just fitted it. The vent pipe outside is still dribbling water when I’ve set everything.
steps I followed : released system pressure, replaced PRV, leaving drain valve open repressurised the EV to 0.9bar. Closed drain valve.
opened cold inlet main feed. Opened filling loop inlet, then opened return valve to bring system pressure to 1.2bar. Closed return filling loop valve then inlet filling valve.
boiler on, hot water demand. Did get a fan error - is that cause the pipe work is empty for example? Any ideas do I need a procedure to get system going again?
think I didn’t set it all right after drain, got a fault code “too much air in system” - ?!
either way, still getting that venting dribble, take it only option is the heatx now?
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Sorry for all the questions at once!
strangely with the boiler off and the cold mains valve shut I still get some water coming when hot tap is on, but I can only assume that’s due to mixer taps, rather than something passing...
appreciate all your help @ianmcd, hopefully I’m almost there to fixing it!
yes can only be the Plate Heat exchanger now
Thanks @ianmcd - would that be causing the dribble? So definitely no more valves or anything like the 10bar dhw valve?
the PRV was pretty cruded up so glad I replaced.
will get the heatx off and see if it can be cleaned or flushed if not will go new.
the airlock - how should I clear that? Obviously I gotta drain again for the heatx but when I put it all back on wanna make sure it’s all done right
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you will have to replace the Plate hex, it is pinholed and mains water is passing into the system water
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