Baxi Combi 80 E

[Agile]

Sorry to be lazy to look up Mi but its more sociable to ask here!

Went to one of these today after two plumbers had failed to fix it! Worked on DHW nothing on CH.

Original fault seemed to be a faulty timeswitch, that seems odd as they are well tried parts but its the third I have encountered recently! Are they a common failure point?

Plumber had changed the PCB but then reinserted the original. I found that it would not start unless the CH NTC was disconnected and reconnected.

I found that ALL four links/dip switches were OFF. Not having MI, I got it working by selecting all four to on. I was short of time as it was Sunday and have to return shortly to replace the timeswitch anyway.

What is the NORMAL setting for each DIP and what is their function?

Tony

 

[Gasman1015]

Normal position for all four is off.

Switches are for :

Pump overrun
Lpg
Anti cycle
temperature

The only reason I know that, I was talking to Baxi tech this morning about a similiar problem, whereby I had to change the pcb to correct the fault of no CH.

However, although the boiler is working, it is no longer burning correctly and I wondered about the setting on the dipswitch.

There is no mention of these dips in the MI.

 

[Agile]

Thanks, thats interesting! Now I wonder why the DIPs are not mentioned in the MI ?

In my case apparently fitting a new pcb did NOT cure the fault but moving some of the switches to ON did cause the boiler to function, probably the anticycle.

To repeat, the boiler is fine on DHW but will not start on CH unless the CH NTC is disconnected and then reconnected !

Where are all the Potty engineers today?

Tony

 

[gstens baxi]

The dip switches are not normally used for uk boilers but are required for the continent. Why are they there is for more technical people than me.

 

[Agile]

To repeat, the boiler is fine on DHW but will not start on CH unless the CH NTC is disconnected and then reconnected !

Moving one of the DIPS, probably the delay, makes it work! A new PCB apparently did not fix it!

Whats the problem?

Tony

 

[Slugbabydotcom]

It all smacks of CH NTC to me Tony
Can you swap the leads over or stick a 1.2 k ish resistor in its place?

 

[Agile]

NTC measures 10k cold which I thought was correct.

In any case it works fine after the NTC is dis and reconnected.

Also works fine if DIP SW is moved to on.

Tony

 

[Gasman1015]

Check resistance against the HW NTC or swop them.

 

[Slugbabydotcom]

NTC measures 10k cold which I thought was correct.

In any case it works fine after the NTC is dis and reconnected.

Also works fine if DIP SW is moved to on.

Tony

Yeah it should be 11k

I have two of these pcbs on the shelf and as already stated the switches are all off although one of them had a leaflet in stating to hold in the reset position for 3 secs before comissioning.
Theres nothing to lose by trying swapping the leads over

 

[Agile]

Where are all the Potty engineers?

Like a policeman, they are there when you dont want them and nowhere to be seen if you do!

Maybe they dont know the answer ???

Tony

 

[Gasman1015]

Maybe they dont know the answer ???

Tony

And you call this sociable.????