Seals in old boilers and POC analysis

[Joamon]

Thanks Fireman, I'm going to give him a call , and get it tested right. Given it's some 45 years old I wouldn't be surprised if the case seal was a little tired, but that seal is accessible, and so if causing a problem something could be done about it I wuld imagine. It was reference to some mysterious seal in the flue that was quoted as being the death of the thing, he mentiioned something about having to take the whole heat excahnger off the wall to gain access, but I'm not sure such a seal exists? There is a sand / cement screed making a good seal from the outside and as far as I can infer only the seals shown on my attachement. Once I have a resolution will update.

 

[Joamon]

Oh and to answer your question I have checked and definitely registered, no doubts there.

 

[FiremanT]

Oh and to answer your question I have checked and definitely registered, no doubts there.

The only combustion seals are after the cast HEX. Nothing behind, so no HEX removal required. Even if the seal between the HEX and the flue was goosed, it still would not effect the kitchen unless the case seal was damaged.

 

[gas112]

The guy is trying to rip you off or is just genuinely stupid and if the case seal is slightly worn these are available as a generic part of the shelf

 

[Joamon]

THanks Fireman and gas 112. JUst found the case seal and as you say is available , so if needed then should be okay on that front.

 

[Joamon]

I'm guessing the case pressure is negative on the 440wrs?, no fans anywhere..

 

[gas112]

yep

 

[ianmcd]

you need a more experienced engineer, I wouldnt even dream about putting a FGA anywhere near that boiler, the readings mean nothing, and no it doesnt have a fan

 

[oilhead]

Whilst a leaking flue seal may not pass leaks into the room with the case fitted, it has got to have some impact on the combustion figures as it will contaminate the air that the burner 'breathes'. If the engineer smelt fumes with the case off, then using the analyser to identify the source is a legitimate operation. I, and many others, have done similar on oil boilers when similar problems caused constant reignition.

 

[FiremanT]

Whilst a leaking flue seal may not pass leaks into the room with the case fitted, it has got to have some impact on the combustion figures as it will contaminate the air that the burner 'breathes'. If the engineer smelt fumes with the case off, then using the analyser to identify the source is a legitimate operation. I, and many others, have done similar on oil boilers when similar problems caused constant reignition.

I know zero about oil boilers - but there are 3 things I DO know about that gas boiler:
1) If ran with the case off, you will ALWAYS get fumes in the room
2) FGA is not required, and using it to test for fumes in a room with a case off is NOT an appropriate method, for gas.
3) It does not have any means of automatic reignition

The nearest to your scenario would be the burner baffling when in operation. But that was never mentioned, and is generally a physical observation. And would normally be the inner telescopic flue (I think it is on the WRS) flue not sealed or corrosion on the combustion flue. But none of these would cause fumes in the room.

 

[gas112]

Whilst a leaking flue seal may not pass leaks into the room with the case fitted, it has got to have some impact on the combustion figures as it will contaminate the air that the burner 'breathes'. If the engineer smelt fumes with the case off, then using the analyser to identify the source is a legitimate operation. I, and many others, have done similar on oil boilers when similar problems caused constant reignition.

absolute nonsense the burner is completely open so would def smell combustion with case off

 

[Razor900]

Condemned by a twelve year old that hasn't seen a proper boiler by the sounds of it.

You should make him change it. With any luck it will fall on him. Heavy old beasties...

 

[kidgreen61]

As Razor says, I'll bet it was a youngster terrified by seeing his first old school indestructible boiler.

 

[oilhead]

I know zero about oil boilers - but there are 3 things I DO know about that gas boiler:
1) If ran with the case off, you will ALWAYS get fumes in the room
2) FGA is not required, and using it to test for fumes in a room with a case off is NOT an appropriate method, for gas.
3) It does not have any means of automatic reignition

The nearest to your scenario would be the burner baffling when in operation. But that was never mentioned, and is generally a physical observation. And would normally be the inner telescopic flue (I think it is on the WRS) flue not sealed or corrosion on the combustion flue. But none of these would cause fumes in the room.

Horses for courses. As an oil burner is totally enclosed within the heat exchanger and there is no open flame, then locating any leaks of POC can be aided with an analyser. It never takes much to contaminate combustion air, and if case sealing is used to make room sealed, then re ignition occurs. If combustion air is supplied through a snorkel, then leaks will contaminate the room. Your comments about baffling are also valid in oil boiler instances.

 

[Joamon]

Thanks all , I hope the trusty beast survives this but will see. No response from the original Engineer, which is frustrating as I'm not after blood - just a logical discussion / reasoning. I have another Engineer coming over tomorrow so shall await the outcome of that.

No mention of baffling.

Right off to boil the kettle...... it's bath time!