Diverter changed and no hot water a full rate

[Pooly89]

Hi Guys,

I wonder if anyone can shed some light a fault I have on an old 24 Cdi BF.

I first of all had hot water call dropping in and out and the primaries getting hot on the heating side, Changed diverter, now no hot water call drop out or primaries getting hot on heating side.

However with the boiler set on MAX hot water, boiler sense flow as above and fires up with tap on a full rate but does not get hot at all, I then restricted the flow rate at tap, then have hot water but not extremely hot as you would expect from a boiler set at MAX and also boiler cutting in and out(assuming plate heat ex. is getting to temp before water is)and obviously a noticeable drop out in temp.

Basically my initial instinct is that the plate heat ex. is to blame due to possible restriction, However although it does take a while for the return pipe to get hot in hot water demand it still does get pretty damn hot, eventually. So I guess I'm asking would flushing the heating side of circuit help or is it best to bite the bullet and change heat ex. or is it likely to a be a temp sensor/pcb issue?

Cheers

Pooly

 

[thereisawizza]

I'd pop the dhw h/ex off and have a look inside, should be easy if you changed all the seals you disturbed changing the div valve. Also might be worth a look at the pipes from the pump for muck to give you a general idea of the rest of it. You could pop the pump head off to check too.

 

[Pooly89]

I'd pop the dhw h/ex off and have a look inside, should be easy if you changed all the seals you disturbed changing the div valve. Also might be worth a look at the pipes from the pump for muck to give you a general idea of the rest of it. You could pop the pump head off to check too.

I Did have a look a bit of black on the inside of the heating connections and I ran some water through the heating side, seemed to be flowing through ok although some small particles came out the first time. central heating works a treat, gets to all the rads quite quickly. That's whats got me confused.

 

[Pooly89]

I'd pop the dhw h/ex off and have a look inside, should be easy if you changed all the seals you disturbed changing the div valve. Also might be worth a look at the pipes from the pump for muck to give you a general idea of the rest of it. You could pop the pump head off to check too.

I Did have a look a bit of black on the inside of the heating connections and I ran some water through the heating side, seemed to be flowing through ok although some small particles came out the first time. central heating works a treat, gets to all the rads quite quickly. That's whats got me confused.

 

[thereisawizza]

WORCESTER 24 CDI HEAT EXCHANGER PART NO. 87161429000 NEW WITH ALL O RINGS | eBay

Def worth a punt on this older model boiler....

 

[Pooly89]

Thing is what happens if changing heat ex. don't work?

 

[Pooly89]

Thing is what happens if changing heat ex. don't work?

Fitted new plate, still same problem only notice must be via the bypass(bypass pipe hot) the heating flow pipe gets rather hot. I have tightened the bypass screw but no such luck. Any suggestions would be a great as feel like im bangin my head against brick wall.

 

[Pooly89]

Thing is what happens if changing heat ex. don't work?

Fitted new plate, still same problem only notice must be via the bypass(bypass pipe hot) the heating flow pipe gets rather hot. I have tightened the bypass screw but no such luck. Any suggestions would be a great as feel like im bangin my head against brick wall.

 

[Aquazone]

I don't think this bypass has a spring etc, just a screw (if memory serves) so maybe just take it out and see if it needs a clean and a new seal? Other than that maybe a call to Worcester

 

[hammers4spanner]

Arnt these boilers about 20 years old?

 

[Pooly89]

Yes mate.

 

[Pooly89]

I don't think this bypass has a spring etc, just a screw (if memory serves) so maybe just take it out and see if it needs a clean and a new seal? Other than that maybe a call to Worcester

I have already called worcester, they were unfortunately only able to go along with my theory of bypass fault. They had no more suggestions. I am facing a rather high flow rate also so I may have the plate back off and fit a new flow regulator, just in case.