Worcester 28i Junior HW not hot enough

[Dylan W]

Hi
I've got an issue with my Worcester 28i Junior not heating the HW sufficiently.
At best it is warm at the taps/shower and when I take the temp of the feed out of the boiler the pipe is reading 44 to 45 deg C
The CH works fine.

I've had various heating engineers saying its the diverter valve. On this model though there isn't one.
From the schematics in the installation manual there two individual circuits that feed through the heat exchanger.

I'm guessing that when the HW is called for the gas valve fires at a 'Hi' burn and for the CH it fires at a lower burn??

There are no fault lights flashing on the boiler, just a lack of Hot water.

Any help on how the CH and HW are controlled would be appreciated.

Thanks

 

[KingDoey]

Should be a 40 degree rise off your cold main if the older style boiler with no adjustment for hot water (they are preset at 55 degrees).

Had one like this the other day turned out to be the plate to plate heat exchanger, which you will require a gas engineer to replace.

 

[king of pipes]

I agree with kingDoey 35 degree rise above the incoming cold main tempreture, partially blocked plate would cause the tempreture to drop off try slowing the flow through the boiler, any good GSI should able to improve things. Cheers kop