Potterton Netaheat Electronic 16/22

[seco services]

the sw live shouldn't be live will no call from heating/hw.

 

[Agile]

The fan may not be allowed to start if the connections to the APS are wrong.

Its all very well you saying the connections "are OK" but how can we know that?

Have you measured the resistance of the fan at the PCB end of the cable?

Can you test to chassis ALL the external connections to the boiler and tell us what each one shows. Then we can decide if they sound right.

Tony

 

[DP]

The APS MUST be in the released state before fan will run. Check the APS is released- a common occurance on this model.

 

[GeoffreySW]

Agile & DP - thanks for the advice on the APS connections. They were arse about face compared with the original unit. Swapped them over and tried again. This time a bit of progress - the 1 amp glass fuse on the PCB blew when I flicked the HW switch.
I checked the fan circuit resistance - it gave a reading of 49 ohms. I've checked the cables from the terminal block & board to the fan itself and they are sound. I pulled the connectors on the fan itself and switched the system back on - the fuse remained intact & I am now getting 240v to the terminal block fan connectors.
I know the fan will operate as I ran it off a separate supply when this problem first occured, but it was probably a 13 amp supply.

 

[Agile]

Have you checked to see that the connections onto the APS are correct?

Tony

I asked you to do that a week ago ! I think you replied that it was fine and I questioned that too ! We have to be persistant !

You seem to say its all powered up but dont say why the fuse blew or if the fan is running now that its got 240v

Tony

 

[picasso]

you do know that this boiler wont start without the cover on,dont you?

 

[GeoffreySW]

OK - I removed the fan this morning and had it tested by an electrical contractor I do business with - it ran for a minute then promptly spontaneously combusted - this explains the 1 amp fuse blowing. The motor must have been on its way out when I put a feed to it last week, but without the electrical knowlege to test it properly I assumed the problem lay elsewhere.

Tony - Sorry about ignoring your initial advice on the APS connections - thanks for persevering with me. Bet you hate people like me posting to this site.

Should have a replacement fan motor tomorrow - will let you know how things progress - thanks to all.

 

[GeoffreySW]

New fan motor did the trick. Finally have heat & hot water again.

Thanks to everyone who took the time to throw ideas at me - and apologies to everyone whose advice I totally ignored - got there in the end though

I have a lot of respect for this site - and although I went a long way around the houses to finally identify & fix the fault on my boiler, at least now I have a much better understanding of how it works and a better awareness of the potential dangers of this model.

Thanks again