Glow Worm Ultracom Boiler Hot water Problem

[9brackendene]

Hi,

I have a glowworm 38 cxi boiler.
when I use the bath tap, the hot water (Draw 12 Litres/Min) goes cold after a minute or so.
This i have been told is because the temp difference between the exchanger input and output exceeds 30 deg C.
My question is once the temp Difference has reduced below 30 Deg C, should the Boiler ramp back up or does it stay off until the tap is turned off and then on again.

Thanks for your help.

Barry

 

[stef99]

Usually it will shut down the whole system.

The reason for the temp difference is usually dirt in the exchanger.

however, I would usually expect the boiler to be over worked.
have you tried running the tap at half open?

if thats the case then turn the hot water outlet down half way.

You will lose half the flow rate, but that is actually quite common.

(or adjust it untill you get full heat)

if this has happened just now and it's been fine for years, I would suggest there's dirt in the heat exchanger.