Intermittent dhw problem

[ianmcd]

You may be on to something. There are green and red. Thought they were red and green on each of the microswitches. Are you saying the Reds should be on the deverter valve and green on the dhw microswitch?
I have a house converted from two but kept two separate systems, the other is also a baxi so could check that and compare.

Green for the DHW flow switch the one at the front of the boiler and red for the system primary flow switch or hydraulic differential pressure switch to give it the correct title. the one that comes out when the pump is running

 

[Mechanic1]

To all those who helped me sort out my baxi problem I would like to thank you all. It would appear that putting the correct wires on the microswitches really makes a difference. Stripped and overhauled the diverter valve and cleaned plate heat exchanger then school boy error!!!
All appears well now......
Thanks again

 

[bazdaman]

Always nice for posters to get back to us after its fixed!

 

[Agile]

But why would anyone take wires off the switches?

Firstly there is no need to and secondly its a recipe for disaster.

 

[bazdaman]

But why would anyone take wires off the switches?

Firstly there is no need to and secondly its a recipe for disaster.

Me, you and all heating engineers know to just remove the securing screw, we are programmed to think logically(mostly), OP has probably never removed the case of a boiler before so forgive him for pulling a wire off! Not everybody can be as good as a top 100 engineer you know

 

[Mechanic1]

You are both correct. Boilers are not my thing. Stripping an engine down and rebuilding , piece of cake, at one time. Now my days spent as a Paramedic putting people back together. School boy errors are allowed as long as you can get a bit of advice from an expert. We all make mistakes, now and again, as long as you learn from them and retain the learned experience to pass on to others less fortunate or experienced as yourself.

 

[Agile]

Well I hope that you don't unnecessarily take fingers off your clients when fixing them!

 

[Mechanic1]

Only if they are abusive......

 

[Agile]

The modern way for boilers and engines is to take a photo BEFORE you take them apart.

I was caught out recently on Performa when changing the DHW switch as I could not remember where a wire went to on the selector switch.

The usual wiring diagram did not show the colours!

 

[Mechanic1]

Can I just ask a further question. Initially I had an issue with the pressure rising in the boiler. For some reason this stopped for months but since I interfered with it the rise in pressure has started again. The filler loop has been disconnected so I presume the only way to increase the pressure in a sealed system is via the dhw supply. Is this likely to be the primary heat exchanger or the dhw heat exchanger. Luckily I was sitting down when I priced one. I think it is okay when just on heating but increased after three separate showers.
Any advice would be appreciated.

 

[ollski]

Would imagine you perforated the plates in the he hx when you cleaned it. Never worth it, just replace it.