Flame failure

Pincher

Had a new central heating boiler put in, commissioned yesterday, Saturday 29th May. All seemed well at 9pm last night, when the engineer left. Programmed it to heat hot water this morning. Found the "Flame Failure" red light on. I can push the reset button, and use the BOOST button on the Programmer to start the boiler, but it stops in a few minutes and the "Flame Failure" comes on again. The "Burner On" green light doesn not seem to come on. The water does get hotter from the few minutes of boiler heating, so it does come on.

The boiler is a Potterton Promax FSB 30 HE, and is brand new.

Waiting for the engineer to return. Just wondering what I could test in the mean time.

Pincher

The plumber put some tap water down the flue to fill the condensation reservoir on bank holiday Monday, and the boiler worked. Ran it one hour a day, and it worked fine, then the Flame Failure happened again on Saturday.

It looks like the problem is to do with the condensation reservoir. It seems that the reservoir gets full, triggers the condensation pump, which empties the reservoir, and the Flame Failure happens.

We are guessing the "reservoir empty" signal is wired incorrectly to the boiler controller, so that the controller thinks it means "reservoir overflow", causing the boiler to shutdown to protect itself.

Calling Potterton to sort it out.

What a farce, the boiler is basically working fine,
but the condensation part is giving grief. I bet the condensation pump will breakdown right in the middle of winter as well. And then it will be out of stock for two weeks, because everybody else will be ordering one too.:mad:

JasX

yup, my initial thoughts were dodgy flame sensor but if your I/O is wired up incorrectly the other parts don't stand much of a chance. ie LOGIC: run pump till condensor tank hits low level.... but if the low level switch and flame sensor are wired up the wrong way round pump has no way of telling when to stop pumping and your low / low low level trip will be telling the system its flame has gone out whenever the tank empties causing the system to think it should be shutting down....

is that not the kind of thing they are supposed to pickup on and recitfy early during commissioning?

Pincher

I don't think he tested boundary conditions.

On the day of commissioning, the boiler ran for over an hour happily. But then it also ran for a week (one hour a day just to test it) after putting the tap water down the flue. The condensation reservoir and pump are integral to the floor standing boiler, hence FSB in the name. The Gas Safe engineer just had to wire the Live, Neutral, Earth and Demand lines.

Anyway, this is just the symptom, I'm sure the Potterton engineer will have some even more bizzare theory to explain it.

Theory B

A family of beettles have settled inside the boiler.
Every time the boiler fires, they think the volcano god is angry,
so they sacrifice the juiciest females on the ignition spark, which eventually causes the Flame Failure.

Pincher

It's a label!

The Baxi Potterton engineer turned up,
and found a plastic tape label on one of the high tension wires leading to the spark assembly. The label was charred around the edges. He replaced the assembly just to be sure. So far so good.

The condensing pump and pouring tap water down the flue shouldn't have made any difference, but it did!? Now we are back to soak testing. Crossing my fingers.

Pincher

Funny thing the Potterton engineers said.

"Old condensing boilers had less sensors, but now they have a test sequence that they go through, so how the LED flashes tells you what is wrong."

"OLD" condensing boilers? I only heard about them five years ago!

JasX

Pincher wrote: »

"Old condensing boilers had less sensors,

an in a fair few cases less things to go wrong as a result