Potterton Promax HE problem keeping it running.

Hi all, sorry my first post is a plea for help but need some advise before i do anything else.
I am Gas safe registered but i concentrate on Power flushing and the odd service for my customers.

We have new neighbors as off yesterday and they came into me saying there hot water was scolding hot.
The only obvious thing was the 3port valve stuck in mid position (house has been empty for 8 months since tenants chucked out for not paying the rent) , so i presumed that was the problem.

Whole system was fitted by british gas about 5 years ago and all pumps stats and programmers have the BG logo on them.

Managed to get to her by midday today, changed said valve and rewired it wire for wire so as not to get it wrong.
I noticed that both pump valves were completely rusted and there was what looked like plasticine around the joint, moved this away and the water ****ed out.
Showed new neighbor and advised this would also need replacing, she agreed.

Took the pump and valves out (they were rusted on solid) and was shocked at what i saw, the gate valve on the outlet side of the pump was closed
Presumed the previous tenants had done this to try and stop the leak.

So off i went and got the new pump and fittings.
Again fitted this and did the wiring wire for wire.

Everything sweet, fired up the hot water only and 3 port slid across to water and boiler fired.
Ran for 20 mins or so all good.
Then turned water off and called for heating
3 port slid to ch and heated up fine...

So turned a few radiators on because previous tenants had turned them off and they heated up, albeit a bit slow.

So was packing tools away and explaining to neighbor how to adjust her room stat (in the hallway)
Noticed the boiler had not fired for the last 20 mins or so.

Being a potterton promax HE the only thing on the front cover is a reset switch.
Pressed this and nothing except a click from the boiler.
Went upstairs to the airing cupboard and noticed that "alarm" was flashing on the British gas box above the power supply.
Pressed both buttons and it disappeared, went downstairs and boiler fired up, but only for about 25 mins then stopped again.
By this time it was getting late and my neighbor had to go out.

So i have switched the boiler off at the moment until i can pinpoint whats wrong, (also noticed flame is orange so wanted it off until i can service it)

Any advise on where i should be looking?

The boiler does need a service as the flame is a noticable orange colour and you can see specs of crap on the burner.


So first thing i will do is service the boiler and check the obvious, fan, condensate etc.....flame devises etc.

Anybody have any experience of this problem on this model?
Have only ever serviced a couple of these and they went fine with no problems.

Sorry for the ramble but i'm off out in a mo and wanted to get as much info on here as possible.

Many thanks in advance.

the "alarm" is on the wireless receiver .so i would gess it is loosing its signal try new batteries

Hi, yes makes sense as i have just changed the batterys in the room stat, they are a right pain aswell, 2 cartridges slide out the bottom and then dont push back up very well.
So thats what causes the "alarm" to stay on then?

All the time the boiler wasnt firing up the room stat was showing a temp and the "call for heat "sign....i think

Is it a wireless roomstat??it sounds as if it needs re-setting with reciever.when u turn r/stat up does the green light come on the reciever?if not it needs resetting.

Yes it is a wireless stat and the power has been off twice today and the batterys have been changed.....

Stupid question now, how do you synch them?....in the dark here with no paperwork at all and only "British gas" logos splashed all over everything.....

Thanks for the help so far....

When u turn power off the bg wireless stats need recommunicating,the red light isnt low battery,it just means it needs to b put in learn mode

you have to reset correctly i think it is batteries removed power off.power on press button 1 green light should ome on boiler will operate, press 1 and 2 red light should flash, put left batt drawer in first then right drawer ,should now controll system, this was off the top of my head so i might not have sequence correct ,

Yes there are 2 buttons on the wireless receiver numbered "1 and 2"
From what i can remember it does say something about "learn mode"

I need to find the sequence lol

Thanks gordon, just to recheck

Remove batterys
Power down
power up
press button 1
press 1 and 2 and get red flashing light
put left cartridge in
put right cartridge in

Bingo..

Lets hope.....

pull down battery draws until power fades
turn off fused spur
turn power back on (red light lit)
press and hold down button 1 then button 2 (red led will flash then eventually go out)
slide battery draws back in
red led will flash for roughly 5 seconds
job done

Thanks guys if it turns out to be as simple as that i owe you guys a pint...

Many thanks...

Right hand battery drawer pushed in first.

Is there any known reason why the right side goes first?
Not knocking the advise just wondering...inquisitive mind

Cos the makers say so. Ok?!

LMAO.....ok point taken