Potterton NeatHeat 16/22 Ignition problem

[adrian2007]

Hello All

I've read the archives, and can see some problems with ignition on the 16/22, but not my specific one.

I'm getting the pilot lit, but no main ignition.

Gas is good, flu is good, voltage right. Have changed the PCB but same.

What detects the pilot ignition? is there a wire that goes to ground or +5v on this event that I can check for to narrow down the problem?

thanks in advance for any help / pointers!

Adrian

 

[GasAid]

It depends if you have a 16/22 Mk1 or not...

The Mk1 has a mercury vapour phial which when heated expands and allows full gas to the burner.

The later models use rectification; ensure the spark electrode is sitting in the flame and that it's surface is clean of corrosion along with the pilot deflector.

 

[kevplumb]

change the ignition electrode

AND CHECK THE CASE SEALS

 

[adrian2007]

Hi

thanks for the tips.

not a mk1, as there is no phial, just a y piece (pilot deflector I pressume) to carry the flame from the pilot to the main burner rack.

The ignition electrode is clean and I don't have a spare here
the case seals are good (as far as visible...)

Will change the ignition electrode tomorrow I guess unless any other ideas?

thanks very the responses!

adrian

 

[pannierstan]

There is actually 3 versions of this old battle axe.

The MK1 has a seperate gas valve and Mercury vapour switch

The MK2 has a white rodgers gas valve which still has a mercury vapour switch but the mercury switch is interchangable and plugs into the end of the gas valve.

Then there is the netaheat electronic version.

Be careful! If you get a spark and the pilot lights BUT you can still see or hear the spark then yes replace the spark lead.
It depends if that does not happen then it might be the mercury vapour switch.

Stan

 

[adrian2007]

I pressume it's the third type that has the PCB, and the other two don't?

do you need to remove the burner rack to change the electrode?

thanks all!

 

[pannierstan]

If you have a PCB then yes its the electronic.

Have you checked my question and the other thing is make sure the polarity is correct.

Sounds crazy but I have had Pott Profiles work for years on reverse polarity then decide they wont

Course it might be the pcb. Check the ign lead with a meter on resistance. Anything less than continuity is curtains

 

[adrian2007]

Hi all
recap, Potterton Netaheat 16/22 Mk3 (PCB)

thanks for your help. The main solenoid in the gas valve had failed... so had the gas valve changed.

However.. after working for a couple of hours it stopped again.

There is power going to the room thermostat and back to the boiler, power goes into the boiler thermostat but doesn't appear to come out again.

Does anyone have a wiring diagram? What are S1 and S2 going into the PCB? What are the leads coming out of the boiler temperature control (twisty knob on the left)? Think they are orange and the S1 and S2 feeds.

many thanks

Adrian

 

[ChrisR]

all at http://www.partsarena.co.uk/baxi/