Potterton Suprima 50 Lock Out problem

EliteHeat

All Suprimas except the 30L have a flow switch fitted. The purpose of it is to ensure that water circulation is taking place as part of its ignition interlock.

This does not mean that your pump - yes, the big red one - is working properly. If the pump is not circulating water quickly enough, then the heat from the boiler cannot be dissipated and the boiler will quickly reach temperature and shut down.

The pump must be at least somewhat working as otherwise the flow switch would not operate. Also, with no circulation the boiler would sound like it was trying to jump off the wall.

If you have an open vented system, check the header tank. If it is about a 1/3 full, put a hosepipe on a drain-off and open it. Check in the loft that the header tanks ball valve is operating. If it isn't you have a blocked cold feed and a shortage of system water is causing the problem. If it is working OK, I would be inclined to change the pump. Oh, don't try and run the boiler while doing these checks!

johnsmith0774

i think it's a sealed system that i have as i can see an expansion vessel and i only have one header tank. from talking to someone else about the problem they asked me put my hand ont the flow pipe just before the pump and see what the temperature was before the boiler stopped.

i was there with my hand on the pipe waiting and all of a sudden it got really hot (burnt my hand a little bit) and thats when the boiler stopped for 2-3 minutes. do you think this is because the pump isn't sending the hot water round quickly enough?

i'm think it has to be the pump because i've tried everything else!

EliteHeat

Yes, change the pump, assuming that your system is still reading at least 1 bar on the pressure gauge.

Wikster

Wikster wrote: »

would it be practicable for myself, as a competent individual (albeit one more used to maintaining computer equipment than central heating!) to get one of the reconditioned PCBs mentioned elsewhere?

As a follow-up, this was the route I took - a recon'd PCB via compumerv and associates on eBay. It was an absolute breeze to fit and has worked perfectly since the day I fitted it 8 months ago. Thanks, moneysavingexpertists R.

meree

i thought i had the same problem.....not until I found out I already had the new PCB.

had an engineer out and was told it was the gas valve...i said ok.

then my neighbour came in to take a look, and discovered it was due to a loose electrical connection to the gas valve!!!!

i swear I checked everything myself, even re-plug the very same connection which I did find it sitting a bit loose...

anyway, he readjusted the pins so tht the plug now sit more securely.

all back to normal.

Atari_Mark

I think I know the answer to this but, I replaced the PCB on my Potterton Suprima 50L in May 08 for the v3 PCB and it worked fine for just over a year but the boiler has now developed another problem. When the hot water and central heating are demanding heat everything works. Once the hot water has got up to temperature the boiler shows a flashing green light even though the central heating is still demanding heat. If the central heating is the only thing turned on, the boiler starts up (fan first then burner) and remains on for 5 seconds before the burner goes out and I get a flashing green light.

I have checked the thermister and it is the correct resistance. The pump must be working fine as the hot water would show the same symptoms so.... do people think it is yet another new PCB?

cheryl_1995

hi
can anyone help please

i av a suprima 30-80 boiler. when u switch heating or hot water on it tries to fire up then trips all the electrics. any advice would be much appreciated. thankyou

keystone

cheryl_1995 wrote: »

hi
can anyone help please

i av a suprima 30-80 boiler. when u switch heating or hot water on it tries to fire up then trips all the electrics. any advice would be much appreciated. thankyou

You have an electrical problem not a boiler lockout problem. You need to get someone in to look at it for you.

Cheers

mark260171

If the fan cant turn at switch on...or at any time at all it will cut everything out and give red flashy light

I just gave mine a squirt of 3in1 oil to get it going and its all running fine now

I have a service call with BG placed and they should replace the fan assy when I explain but in the short term my wife and kids are warm

simeon

Wikster wrote: »

As a follow-up, this was the route I took - a recon'd PCB via compumerv and associates on eBay. It was an absolute breeze to fit and has worked perfectly since the day I fitted it 8 months ago. Thanks, moneysavingexpertists R.

Ditto! Lovely to have a warm house and reliable hot water again, all at less than the cost of an annual boiler service. Thanks to everyone who shared their advice and experiences on this forum.