Isar HE30 bangs when hot water is turned on

[diypj]

My boiler is 3 years old. From long time ago it developed an annoying problem that when you turn on hot water while central heating is on, you get a big bang from the boiler, you can see the pressure gauge oscillating a lot when this happens. The boiler works perfectly for 3 years now but this banging worries me a lot. It seems when diverter valve switching from CH to DHW, the pump is still working, but when it switches from DHW to CH the pump stops for little while and therefore no noise comes out. I would assume it's a pcb problem, like a software bug in the circuits where the pump is not told to stop when diverter switches. Or probably it's only a faulty diverter? But the boiler has been working for 3 years no problem but only the annoying banging.

Searched in the forum, seems some other guys got this problem as well but none of them left message what's the problem in the end. Can someone spare ideas on how to fix this? Will new PCB help? I noticed Ideal released a new version of PCB to replace the original one. Thanks in advance.

Peter

 

[gas4you]

I would go for the DV myself. These are known to be problematic on these, but come to that so are most of the parts

 

[gas_man_gaz]

is it the m30100 model? ive had loads doing it!! normally i just contact ideal to do the job as they change a few parts.. but its mainly down to the diverter. could try contacting ideal and see if they'll do it under warranty

 

[Agile]

Its quite easy to open the diverter and clean and silicone grease the moving plunger and the body.

I dont know if the pump is meant to stop on both valve transitions. It would seem logical but boiler designs are often not logical.

Tony

 

[corgiman]

could be one of those Non Honeywell Diverter valves they fitted, they can bang louder than the sh1thouse door when the plague is in town

 

[diypj]

Thanks for all your help.

The boiler is HE30. The diverter is marked as CP type. The alternative replacement is Wilo. Is Honeywell diverter compatible with Isar HE30?

 

[the.ideal.man]

i used to work as an engineer for ideal boilers, you can fit the grey honeywell diverter valve to the old cp hydroblock but you need to change the complete left hand hydroblock, we used to change loads and loads at ideal!! they were ****e. if you contact ideal they will come and do the job for you for a one of charge of 200quid. it is definately the diverter valve, the red headed ones were really poor, they went back to the original grey honeywell valves in 2007. im just glad i dont work there anymore, i moved to a proper boiler company....worcester bosch.

 

[Agile]

You have replied to a year old posting !

However you may be able to give us the benefit of your experience to answer the HE24/30 L-F intermittent fault. There is a thread on here a few days ago and another in 0rhe CC which I started.

Tony

 

[gas4you]

i moved to a proper boiler company....worcester bosch.

You reckon! I wouldn't fit a WB as long as I have a hole in my ar*e