Ideal Isar HE30 Leaking, Diverter Valve Not Closing

[Strike Team]

My Ideal Isar HE30 leaks at the point where the diverter valve connects to the plate heat exchanger. It gives an intermittent intermittent H3 (domestic hot water thermistor fault) error code. The diverter valve is not always operating properly - the radiators start to warm up when the boiler pre-heats the plate heat exchanger. I've removed the diverter valve and plate heat exchanger and washed quide a bit of dirt out of the closed-loop side of the heat exchanger. Testing the DHW thermistor with a multimeter gives a sensible reading, suggesting the thermistor problems were due to water dripping onto the wiring.

Is the dirt in the system the cause of the problems? Is there a better way to clean out the heat exchanger than rinsing water through it? Am I best to attempt to grease the valve, or is replacement best? Is flushing out the radiator system a good idea?

All help appreciated.

 

[onlyfitidealboilers]

did you not replace the plate seals when you removed it? if not, they are going to leak arnt they

 

[Strike Team]

That's a good idea. I haven't refitted the heat exchanger yet, I want to get it thoroughly cleaned out and understand exactly what went wrong before reassembly.

 

[onlyfitidealboilers]

did you turn the boiler off or have you been away??

 

[Strike Team]

Yes, I turned off the boiler, water and gas when the problem started. I had to remove and clean out the water isolating valve first as it was jammed with dirt.

 

[entreri911]

probably be easier just buying a new divertor catridge than trying to clean up the old one, not to expensive either