Combi Boiler hot water problem

[JamesThompson]

Hello all, I have a few queries. Firstly:

I have a combi boiler, a Worcester CDi RSF. Not a condensing type. The hot water doesn't come on anymore, the boiler does not fire up. The heating I tried to see and that worked fine.

I believe the problem to be the diverter valve diaphragm. I have tested the microswitch and when pressed the boiler fires up.

My question is, I have the boiler instruction manual but it seems tricky to replace, I have to remove many parts to get to the diaphragm. Is it not the best for a DIY person to fix, and if so, am I allowed to legally do it?

Thanks for helping all

James

 

[ChrisOxford]

If the boiler doesn't even try to fire (or the DHW demand light come on)when you open a hot tap, it will almosts certainly be the flow swtich that's faulty.

If it's the model I'm thinking of, it's not hard to change, and because it's on the secondary side of the water-to-water heat exchanger, you don't have to drain the boiler, just switch off the mains water and electricity.

 

[JamesThompson]

Hi Chris

The boiler has a diverter valve and plate heat exchanger. It says in the manual to remove the filling loop assembly, plate heat exchanger to get to the diverter valve. It is a Worcester 24 CDi RSF

 

[muggles]

You can theoretically DIY it but be warned, it is a complete pain in the asre to do

 

[BlueMoonMole]

It would normally take around 45 minutes to an hour to do (for a competent engineer)

If you want to DIY it, set aside a morning.

You will need a good selection of hand tools such as screwdrivers and spanners.

You will also require a Giovanni Universal Diaphragm Kit.

And patience. Lots of patience...

Start by draining your CH circuit, turning off your cold mains and running your hot tap until it stops....

Then start from your left, and working to your right, start pulling things out



AAAAAAND all back again, in reverse order.

Don't forget to replace that pin!

 

[ChrisOxford]

Why would a failed diverter valve cause the boiler to stop responding to DHW demand?

Or am I being thick?

 

[ChrisOxford]

Just read the MIs

Or am I being thick?

I was Ignore everything I said.

 

[JamesThompson]

Will I need new o-rings and fibre washers as they seem to have these on the parts that I will be removing? If so I'd like to have them ready before I start!!