28 cdi service kit

[huddster]

had a 28cdi with hot water not coming on, customer has to turn tap on and off a few times to get it going.

tested the micro switch all ok, so decided to take the diverter valve out and replace diaphragm with a service kit, got everything out and the diaphragm is is shot to pieces (happy days) as i was about to replace it i notice the spindle on the diaphragm was shorter than the one i took out, went back to the van and found another kit which was the same length.

got everything back together and was quite happy that i was going to turn the tap on and have lovely hot water......... but nothing!

the spindle is still not coming out far enough to make the micro switch. so after all that work ive ended up sticking a washer to the end of the spindle cap, which has solved the problem but its a bodge and probably wont last that long.

the flow rate was good the diaphragm and spring are in the right way around, so i was just wondering if anyone else has come across this or knows of anything else it might be,

also just to note the customer has always had a problem with the DHW and has had to mess about with the taps to get it to come on. she has lived at the address for 15 years

any help would be appreciated

cheers

 

[rm1]

what is the incoming cold water pressure to the boiler, did you check for any inlet filter that may be partially blocked

 

[diamondgas]

Is the Diaphragm moving the diverter enough to shut off the heating circuit?

 

[huddster]

well the flow is really good so im sure any partial blockage in a filter would give be fairly obvious but its flying out the taps,

i had the heating running opened the tap and the heating remained on but with the washer glued on the dhw comes on fine and is lovely and hot, although i did not test the flow pipe to see if it was creeping through

 

[diamondgas]

As long as it works eh *shrug*

I use to use a washer on the old 9:24's .. didn't know it worked on the CDi too 😀

May be worth seeing if the diverter's closing fully though eh? 🙂