Alpha CB28 - DHW DIVERTER

[HuDSoN1]

Hi

I hope some one can help.
The diaphragm needed changing on our boiler, so ordered a new one as all was good.

However when we opened up the diverter we found that the shaft in the diverter had snapped on the c-clip.

Could someone be so kind as to provide a part number for this shaft.
I have also marked it in the attached image just to make thing clear.

diverter shaft

• HuDSoN1
• 3 Jan 2009
• 1

 

[Agile]

I doubt that its available as an individual part.

Commercially, on this model most engineers prefer to replace the whole valve as otherwise we would get called back when another part of it has failed and be expected to fix it free!

You might find someone with a removed valve who would post just that part to you!

Tony

 

[HuDSoN1]

thanks for the rapid response.
makes sense, maybe we will go down the new diverter route, just seems like a waste of parts to me but I guess we could keep them as our own spares.

does anyone have one of these that they have salvaged?

 

[mickyg]

I would contact Alpha, it may be available as part of a service kit. Paul Barker might know if he's about.

 

[Paul Barker]

Doesn't make any sense to me. The pushrod wouldn't snap. But it is in two parts.... I don't have any Alpha parts hanging around they all had to go back and even then they sent me a hefty bill for spoilage.

99 times out of a hundred you only need a flowswitch 9 times out of 10 you only need a diaphragm. 1 time in a hundred the water section is problematic.

Relative to other diaphragm diverter valves this is a very reliable one. The flow switch is carp.

 

[HuDSoN1]

Doesn't make any sense to me. The pushrod wouldn't snap. But it is in two parts.... I don't have any Alpha parts hanging around they all had to go back and even then they sent me a hefty bill for spoilage.

99 times out of a hundred you only need a flowswitch 9 times out of 10 you only need a diaphragm. 1 time in a hundred the water section is problematic.

Relative to other diaphragm diverter valves this is a very reliable one. The flow switch is carp.

yep thats the push rod and yes its in 2 parts.
1 part is held within the diaphram and the other is in the diverter.
its this diverter part that has snapped.
about a 1/4 of the way along it had a notched section that i think is for a c-clip (did not find this, prob washed away). as the notched bit is very thin, this was where it snapped.

its not looking good for a replacement then.

thanks everyone for your quick advise. i need it in this weather

 

[Agile]

This notched section is not the groove which operates the microswitch by any chance?

It seems to me that you would be better off replacing the whole valve just as I would!

Tony

 

[HuDSoN1]

This notched section is not the groove which operates the microswitch by any chance?

It seems to me that you would be better off replacing the whole valve just as I would!

Tony

no its the join between the 2 rods that operates the microswitch.

 

[Agile]

Can you accurately measure the length of the rod and the distance to the clip grooves?

Its just possible that its the same as the standard Gianonni shaft. A long shot perhaps but I have an old one I could send you.

You have to understand that we dont have time to fiddle about with the innards. If we did then we would have to charge for our time and the cost is better spent on a new valve so that we can walk away knowing it will give no problems for at least five years ( well four years on an Alpha then! )

Same valve as a Ravenheat Little Star I think.

Tony

 

[HuDSoN1]

Can you accurately measure the length of the rod and the distance to the clip grooves?

Its just possible that its the same as the standard Gianonni shaft. A long shot perhaps but I have an old one I could send you.

You have to understand that we dont have time to fiddle about with the innards. If we did then we would have to charge for our time and the cost is better spent on a new valve so that we can walk away knowing it will give no problems for at least five years ( well four years on an Alpha then! )

Same valve as a Ravenheat Little Star I think.

Tony

Hi Tony

Thanks for the offer.
I have been looking in to this and I think you are right about the little star DHW diverter being a Gianonni and thus the same as what is in the alpha.

I could not get back with the push rod details stright away as I needed to pull it out of the boiler again, however I do have it now.

The push rod is 68mm in total lengh.
It is tapered at one end (for the microswitch).
the notch for the c-clip is 18mm in from the tapered end.

Does this match up with the spare you have?

 

[Agile]

The Little Star does not use the standard Gianonni diverter it uses the "special" one like the Alpha.

It was worth the try but the standard gianonni is apx 60 mm long with two grooves each apx 24 mm from each end.

So unfortunately its not the same.

I suspect that you are going to have to get a complete valve just as I would always use. Can you imagine how I would explain to a customer that I had just snapped her shaft?

Tony

 

[HuDSoN1]

thanks for checking for me.
a new one it is then. at least i wont have to clean up the old one