worcester 28CDi diverter valve info needed

[scott2]

I have managed to narrow a fault on our 4 year old 28 cdi boiler down to the diverter valve,we have no hot water unless the central heating is engaged, the actuator rod on the end of the valve doesn't come out far enough to press the microswitch and light the boiler, can anyone tell me whether i can fix this or do i need to replace the whole thing, thanks

 

[corgiman]

it will need replacing I am afraid the diaphragm is dead so you have to replace the whole diverter valve assembly

 

[ChrisR]

Possibly just the diaphragm needs replacing, but it's a lot of work for a small thing.
Many pros would change the whole diverter valve, for fear of having to do all the work again if the DV shaft is seized (common). As diy, it wouldn't be unreasonable to try the diaphragm alone, assuming you enjoy a challenge.

 

[fitz1]

plenty of silicone grease

 

[nickso]

diaphragm can be done without removing the diverter, as chris says it could also be the diverter but id take a chance on the diaphragm on its own....will save you a lot of hassle

 

[fitz1]

theres no direct replacement for the 28 cdi. you have to get the 24 cdi and strip it dqwn to use the diaphram rubber on the old rod and spring.

 

[nickso]

theres no direct replacement for the 28 cdi. you have to get the 24 cdi and strip it dqwn to use the diaphram rubber on the old rod and spring.

thats surprising, ive never had any problem with either model with the giannoni kit i use

 

[ChrisR]

Where are you getting your bits, fitz? Email me..?

 

[fitz1]

if i remember rightly , the spring is slightly different and can cause the 28 problems.

 

[ollski]

Same valve, same part number. Standard diaphragm kit comes with all the o rings and washers you need to replace on reassembly and a 90 degree draper screwdriver will let you do it in situ in a couple of hours.

 

[scatmanjohn]

Its exactly the same part in both.

Part No: 8-716-156-746-0

Fits on 24Cdi , 28 Cdi, 26 Cdi extra , 35 Cdi 2