Grant 26e External oil powered no hot water ( running cold)

[Steve Mag]

Hi folks, have a grant 26e outside oil burner.
Currently the heating is ok but no hot water runs but is cold. Fires up on water, flow switch is ok, pump ok, demand light and flow light comes on as it should. just noticed If I leave it on hot water the pressure creeps up to 2.5 bar ( from 1.5 on heating) and it locks out, but it will run all day on heating. If have taken the TMV valve off and cleaned it however the hot pipe from the heat exchanger going into the TMV is cold and the heat exchanger is also cold. Given It locks out when trying to heat the water is this pointing towards a duff or blocked heat exchanger, Any help in the right direction would be very much appreciated.

Cheers

Steve

 

[oilboffin]

If the hw pressure is ok then take off the hex and clean out the heating side with a mild acidic cleaner.could be faulty pump but seems like you could do with a decent engineer.Bob ps could also be blocked non return on hw pump.

 

[Steve Mag]

Cheers Bob, i'll take it off next week and have a look as I in live up in the North Wales hills we are in for a cold weekend and Idon't want to bugger the heating side.
As we have 6 English setters we also have a portable calor water heating for dog bathing outside so we have some hot water albeit a lot of faffing about.

cheers

Steve