Ideal isar HE30 sounds like a motor bike and gauge bounces.

[massgsm]

Ideal isar HE30 sounds like a motor bike and the pressure gauge bounces, on demand for domestic hot water (d) and on domestic hot water preheat (t), this is an intermittent problem.

BG have replaced the orange PCB module (twice), condensate trap, DHW heat-exchange, diverter valve cartridge and diverter motor head (red). CH is working without problem and the CH pipe does not get hot on demand for DHW. BG's chief engineer for our area is now baffled and is thinking about bringing ideal out.

The Isar is 6 years old, in a hard water area, and to be fair its performed well until now but BG are now baffled. Any ideas guys?

 

[dancinplumba]

wondering whats your cold mains pressure pls ???

 

[massgsm]

Pressure is excellent and flow is about 10/12 litres per minute.
Forgot to say that the hot water takes a long time to become hot, almost like the pre-heat is not working.

 

[e/bourneplumber]

how about the gas valve not opening / sticking occasionally. not enough heat input to heat the hw water but ch heats up eventually ie it takes longer than it should. i get that noise sometimes on remehas when purging through the gas

 

[Anton]

If it's doing this on pre-heat AND when hot water is drawn, then it's more likely to be related to a circulation problem within the boiler primary circuit. It could be a loose pump impellor or a blockage within the boiler. Have their engineers used a device called a 'LIMPET' on the pump? It is a collar that fits on the pump supply cable and plugs in to their laptop. It measures the pump speed in RPMs. The higher the pump speed the more chance the pump impellor is loose or there is a blockage.

 

[Ricco]

Ideal had problems with noise with the red diverter and so went back to using honeywell type. Sound like this is the problem your having.

 

[massgsm]

Thanks Ricco, you are spot on, there is a known problem with the CP diverter assembly on the isar HE. Changing the whole assembly for the latest Honeywell diverter assembly did the trick.:winkiss: