Vaillant TurboMax 242/1 NG Combi Repair

[Davidalexjeffs]

We have a Vaillant 242/1 NG Combi boiler which has been well serviced over the many years its been in. 1992-96?

Combustion readings perfect for CO2% and ratio/ppm etc

We have a pretty decent cold mains pressure at all cold outlets, even with a few cold taps open, still a decent flow/pressure.
I didnt use the weir gauge as this wasnt an issue.
When hot tap opened at GF kitchen sink, a pretty decent flow/pressure so no issue here.
Then when we leave the hot tap on at kitchen, we have no hot water, infact no water at all, at the upstairs hot taps.

I suspect the plate heat exchanger is scaled up as never a scale inhibitor fitted.
I didnt want to change the plate heat exchanger for the customer if it doesnt improve things.

Could it be anything else?

I explained that old combis could only offer one hot outlet at once but the issue is that the hot outtlets have no water coming out at all?

If its not the plate heat exchanger, then maybe divertor valve?

 

[Riley]

Won’t get any answers on diy boiler repairs mate unless you’re gas safe. If you are send a pic of the front and back of your card to @Harvest Fields @ShaunCorbs or @Riley and get your posts over 10 and we will get you into the gas safe area