Ideal Isar HE30 Boiler – H3 fault

[BRUMILAD]

Ideal Isar HE30 Boiler – H3 fault
Hi Everyone
Need some Help! My boiler has started getting H3 fault code a few days ago – after resetting (turning it off) it would sort it self out, but yesterday Morning (Friday) it just did not want to know, but this morning it started working again ?????
Reading a few of the topic/post its kinda confused me? ? i don’t want to fix the boiler myself but don’t want to get ripped off so trying to workout whats up with it.

This is what Ideal say the H3 code is;
DHW Thermister fault, attempt reset. If still H3 - Engineer visit required.

I have had the PCB replaced coming up to a year ago by npower – any one got any ideas?? I would be very appreciative for any help – so i can stop pulling out the little remaining hair i have

Thanks

 

[BRUMILAD]

"Bump" to the top

 

[BRUMILAD]

The boiler gone off again....

 

[gas4you]

It may sound too obvious, but how about replacing the DHW thermister

 

[BRUMILAD]

I know !! but some of the other ideal thread (and there a lot) peeps are telling you it could be this or that. Its like it cant be the easy ans !!

But the family getting fed up will have to get someone out !

Thanks for the reply

 

[BRUMILAD]

Anyone know where i could get a DHW thermister today ? Been told have to wait till Monday. Live in Birmingham.
I know “patience” but i have none

 

[idealnumber1]

come to liverpool i'll get you one if your that impatient

 

[shambolic]

I have loads although I am just outside glasgow! H3 is defo dhw thermistor

 

[BRUMILAD]

come to liverpool i'll get you one if your that impatient

i would but its started working again

I have loads although I am just outside glasgow! H3 is defo dhw thermistor

Cheers Mate !!

 

[shambolic]

H1 flow thermistor H2 return H3 dhw H4 flue stat H5 wrong pcb tapper settings.
Just make sure there is no water dripping onto wires to stat as this could give intermittent h3 fault to

 

[Agile]

If its the DHW thermistor that measures the plate HE water inlet temperature I think that its is a special type and not like the flow and return ones.

When I was checking a while back I seem to remember it was not in stock at many HRPC branches.

Tony

 

[shambolic]

If its the DHW thermistor that measures the plate HE water inlet temperature I think that its is a special type and not like the flow and return ones.

When I was checking a while back I seem to remember it was not in stock at many HRPC branches.

Tony

Your right Tony its a longer one that goes into the plate (wet pocket) not dry like flow and return clip on ones!

 

[BRUMILAD]

Hi Evryone

Thanks for all the reply and it was the DHW thermistor got it changed working perfect now

 

[hect]

If its the DHW thermistor that measures the plate HE water inlet temperature I think that its is a special type and not like the flow and return ones.

When I was checking a while back I seem to remember it was not in stock at many HRPC branches.

Tony

It IS a wet pocket thermistor, and its on of those that resistance should be 10kohms at 25 deg....

H3 would show either open circuit or 0 resistance....

 

[markbewlay]

Sorry to bump an old thread but not sure if this question deserved a thread of its own.

I have an Ideal boiler and all seemed ok with it until recently. At the moment, central heating and hot water are coming through ok but when the boiler is not required to heat (so central heating is off and taps are off) it periodically kicks in with the H3 status. Now from reading the forum this suggests something is broken, but we have just had a service done (I am a tenant) and I brought this up with the gentleman who came around and he said that this status can occur becuase of the cold weather we are experiencing at the moment.

Just wondered if he was feeding me a line or whether he was been genuine. In fairness the problem did coincide with the cold snap we are currently experiencing but this could be a total coincidence.

Thanks

Mark