Flashing light on Potterton

[Lorna]

The Pump Fault/Low Pressure light on my Potterton Performa System HE has been flashing intermittently for nearly 2 months now. I have so far taken 5 days of my annual holiday entitlement waiting for plumbers to fix it - First 2 didn't turn up, 3rd admitted he didn't know what was wrong, 4th replaced a perished diaphragm and 5th said there was a lot of air in the system, hence lots of churning noise when it does come on and that I would just have to keep bleeding radiators and re-pressurising system until all the air was cleared. That was a week ago. System works ok if I have used immersion to heat water first, so I had to wait until hot water gone. Switched on CH tonight and sure enough boiler not working and light flashing - but the rads don't seem to have any air in them. I don't know what to do next. If it is an airlock how do I get rid of it? Boiler is just over 2 years old and is in the attic.

 

[jpm]

Could be the primary flow valve rod is jammed/blocked or stuck or a damaged pcb sorry can't be more specific I havn't a manual for it.

 

[Bob Croft]

Lorna, I had a look at the manual for your boiler on a DVD I have. In the first instance you need to make sure the system pressure is OK and that the automatic air vent cap (usually a small black cap like a car tyre valve cap) is opened slightly.
If you top up the system pressure and then the pressure is lost in a few days you need to find out where the water has gone.
I could list things to check but really you need a heating engineer who is familiar with this type of system. The manual has a flow chart of items to check and is a useful guide to an experienced engineer. You need to find an engineer who can fault find and diagnose the problems with your boiler.
Bob

 

[newbie1]

hi lorna
when boiler was fitted was the system powerflushed and when you bleed the rads what colour is the water
when system is running does the pump make any noise other than a low hum as it pumps the water
can you describe the exact set up on your syst and is the pressure gauge on the right hand side staying at same pressure or are you loosing water it will rise when the boiler is working but if left overnight is it dropping
its possible the syst is sludged up and so the pump cant pump the water freely round the syst also if loosing water check the pressure release valve that runs outside to see if it has been loosing water here
the auto air vent if working correctly shld take care of air in the syst
what part of country are you

 

[Lorna]

Bob – Thanks -the system pressure is holding up ok. It dropped after I bled loads of air out of rad about 6 weeks ago, but after topping up it has stayed fine. I’m pretty sure engineer no 4 checked the air vent cap. I thought by paying £299 to get Potterton’s engineer to come out I would find an engineer who could diagnose the problem, but neither of their engineers have resolved it. Is there any possibility that last one was right and it is an airlock that I could get rid of if I knew what to do?
Newbie – The system wasn’t powerflushed, but the water runs clear. One engineer thought the pump was making struggling noises. The pressure gauge is on the right, and isn’t dropping below about 1.5. Last engineer said system would take care of small amount of air, but that loud water churning noise when first switched on suggests masses of air. Last night rads finally warmed up after 3 hours although light was still flashing. Would just leaving it on all day help? I live in Berkshire – the limescale capital of the world!

 

[newbie1]

hi lorna

firstly as it wasnt powerflushed then the warranty from potterton would be void as all manufacturers state that to commission the boiler system has to be flushed to avoid the gunk from previous system from getting fed into their nice new boiler and most importantly the pump
my guess would be the system is possible sludged and that some of that has got into the boiler pump and slowing the flow causing the pump to struggle and make the electronics think the pump is faulty as there is prob a flow switch somewhere thats getting confused
air will eventually work its way out the auto air vent and the bleeding of rads from highest point as air rises will help but remember to top up the system each time
where in berks are you my son is a gas safe engineer based near heathrow if you get frustrated and he also has a kamco flusher for cleaning out heating systems|(see kamco website for details of benefits)
rgds paul

 

[Bernie2]

Hmm!

I assume, that the pump and auto air vent are working?

It sounds like air, but then so do many other things. The problem could be, that because the boiler is in the attic the water main pressure isn't quite strong enough to drive it out.

My thinking is, that if the mains water pressure where stronger the more obvious boiler to install may have been a combi.

But if there is low pressure then the next best to a combi or unvented cylinder is probably a system boiler and cylinder.

Although it may have been a case of adequate mains pressure but not enough flow from a combi.

The problem seems to lie in the usual place i.e. DHW cylinder coils.

So if its air trapped in there, it may be a bit hard to shift. The problem is the air may be compressed enough to stop the circulation but also show on the boiler pressure gauge that the system was fully pressurised.

The first thing of course would be to feel for a flow through the cylinder by holding the bottom Primary pipe and the top.
But even this can show up as being alright, as sometimes heat is conducted through the copper pipe rather than the water and can feel a bit like a temperature difference which you get with circulation.

Its also possible I suppose that when the immersion heater heats the water it expands the air and releases it a bit at a time, but not enough to get ir all out.

Anyway unless you can check for air in the coil easily, it may require a Plumber.

 

[bobpape]

My Potterton Performa 28 has just developed a similar problem,
Red light flashing on the 50 mark,
Wont fire up
No spark
Fan makes an attempt to turn but stops immediately,
I provided fan with a temporary 240vac supply and it ran at high speed so fan is probably ok,
Questions are
Is fan speed modulated or simply two or three speed and how is the speed
controled
Assuming something on the PCB does it, anyone any idea which item it is.

Incidentally I am not Gas Registered anymore but the boiler is my own
property so I dont need to be registered to maintain it.

The boiler is 6 years old

Thanks in anticipation,

 

[Lorna]

This morning, with pump failure light still flashing, I ran the taps until no hot water left then switched both CH and HW on with thermostat set high and left them all day. Got back to (very) warm house and hot water and no air in rads. I'm just left wondering how long I should leave it on if this approach has helped shift the air?

 

[bobpape]

By the way I ended up replacing the PCB on the Performa 28,
much to my annoyance because it was fairly obvious that either a relay
or the accompanying resistor had failed,

I identified the problem as the fan attempting to start and cutting out
immediately and traced it back to one of two similar specification relays
on the board,

When I phoned the technical department and asked them where the fan
relay got its instructions to start from, was it a pressure switch, was it a
flow switch, where was it located, the guy could not tell me,

I also asked why they dont use plug in relays as they do in cars.
Actually I was not expecting an answer and I was right, I did not get one.

By the way I am not a RGI.

 

[Puddle]

Its would probably not have been the relay on the board,it would have been the flame detection system faulty,common fault on this boiler,the fan starts but when it activates the air presure switch and does sequance check, it thinks burner is already on due to faulty readings through pcb, so closes down but as you say the fault is a few pence resistors but new board required but thats the frow away world we live in,only trouble is the things we are now throwing away can be quite expensive ,but very profitable for manufactorers

 

[Bernie2]

Must admit been looking into boiler pcbs and think that most of them seem to be made cheap in the Far East. But the prices over here are ridiculous. Potterton nearly got done by the Trades descriptions people for the poor quality of their boards.

As this recession bites even more, I suppose all we will get is poor quality stuff at high prices. The government should do something to safeguard the people its no use letting market forces do it, all that seems to do is make companies more money. But then Adam Smith the inventor of market forces theory did say there would be winners and looser's. And I think plenty of people know who the loosers are likely to be.