isar combi boiler

[arthurhill2211]

my boiler displays h3 does anyone know what this means .the boiler is an ideal isar thanx please email me answers @ [email protected]

 

[BOB D.O.L.E]

my boiler displays h3 does anyone know what this means .the boiler is an ideal isar thanx please email me answers @ [email protected]

DHW THERMISTOR ERROR)

Remove the boiler DHW thermistor from the plate
heat exchanger and disconnect thermistor wires.

Check resistance using a suitable multimeter
connected across the thermistor’s terminal pins
At 25 oC expect 9,700 - 10,300 Ohms
At 60 oC expect 2,400 - 2,600 Ohms
At 85 oC expect 1,000 - 1,100 Ohms

Are the thermistor values correct ?

if no Replace the thermistor

if yes Is there continuity between the
PCB and the thermistor ?

if yes Replace PCB
if no Check and replace wiring as necessary

 

[holyjim]

Many thenks for all sugstions. I have not replaced the PCB so it seamed unlikly to be the problem unless it was in nead of replacing and in line with all advice offered I have called in a plumber who will proberbly suck in his breath and say, @ Well I think if you flick this switch here and give alittle tap there it will all start to work nicely!' however if it gets the heating going in this cold snap it will be cheaper than replacing burst pipes when everything freazes. Again many thanks to one and all for you advice andf comments.

 

[gas4you]

Don't forget the HW thermistor is in a wet pocket