Replacing diaphragm in diverter

[logik]

I have bought a pair of new diaphragms for my boiler. I'm hoping it will cure the problem of both CH and DHW pins being open at the same time, the CH pin seems to be "sticky" and not always notice when DHW flow is requested.

I have the two new diaphragms, is this all I need to replace? Some of the guides I have read appear to have new pins too, as long as I lubricate with silicone grease I assume I am OK to reuse what is there?

I'd also like to clean out as much of the internals as possible, but I don't think I can remove the heat exchangers without new O rings to replace the old ones with? I might just have a go at the diverter first and see if that helps!

 

[namsag]

YEP clean the 3 pins of any scale etc give them a smear of silicone grease (no need to replace them).

If you want to take out the plate heatexchanger to clean it you should be ok without the need for new seals.

 

[logik]

Excellent, thanks! Apart from the diverter, heat exchanger and CH return/cold inlet filters, is there anything else I can easily clean without completely dismantling the boiler?

The pump sometimes makes a bit of noise but I don't know how easy it is to clean, can anybody advise whether it is worth it? Essentially I am trying to squeeze a bit more life out of an old boiler to see if the annoying problems can be fixed in a day, otherwise it will be a new boiler

 

[Agile]

Evidently both of you have some special communication so that you both know exactly which boiler model you are discussing.

For the rest of us without those psysic powers it would be interesting to know if its a Baxi or a Biasi etc.

Tony

 

[logik]

My apologies, should have shared the mind-reading

It's an Alpha 240E.

 

[Agile]

Which is pretty much like the Baxi then!

In that case change the DHW flow switch gland and crean the pin well.

The small DHW switches often fail too so before assuming the DHW diaphragm has failed check that the pin is NOT coming out fully.

I have to say that I have NEVER yet found a system flow switch diaphragm to have failed on that model. There are many other causes of that pin not moving enough to operate the switch.

Tony

 

[logik]

Thanks for such a quick reply. Actually the DHW pin moves correctly and appears to initiate demand. However the CH pin does not always move in, meaning both are out at the same time. I assumed this was wrong and could be the diaphragm, hence buying the parts!

 

[namsag]

Really simple Agile click on there name and hey presto previous appliance mentioned previous comes up.
OP dirty pin will stop it returning properly

 

[logik]

Thanks for the suggestion. I'll give it all a good clean, replace the diaphragms and see if that helps.

Let's hope it's not too cold at the weekend

 

[logik]

I have to say that I have NEVER yet found a system flow switch diaphragm to have failed on that model. There are many other causes of that pin not moving enough to operate the switch.

Sorry for the late reply but thanks! You were right, the diaphragms looked almost as good as the new ones I bought

I cleaned the pins and lubricated them and both now move freely. The boiler works a charm after replacing the CH thermostat. It even switches from DHW to CH seamlessly

Just a problem with a noisy flue fan now that it stays lit for more than 10 seconds, so I'll have to find someone to come have a look.

Thanks again, excellent advice and it has saved me a lot of money.