Up & Down CO/CO2 Ratio

[ISM]

Just got back from a breakdown on a Glowworm Fuelsaver MK2, fixed the fault and gave it a good service, as the customer commented it not been done for at least 5 years!! Stuck the analyser and I could not get a reading to stablelise.

I was getting readings of 0.0040, 0.0073, 0.0021, 0.0095 and CO readings generally really high, at one point it was 1982 PPM!!

Burner pressure ok, working pressue ok, burner ok, seals ok, flue ways ok. It was however, slightly windy down the passage where the flue was.

I had to leave the appliance AR and informed the customer I would pop back tomorrow, with the hope that it will be less windy to get a fairer test, but I am wanting to know if anyone has ever experienced this, because as to yet I have not. Also, would these fluctating readings point to a defective part within the appliance?

Any thoughts welcome.

 

[andyg0507]

firstly is your gas analyzer calibrated, secondly where were you taking test form using you analyzer?

 

[snowhead]

Stick your analyser in your own boiler flue before you go back tomorrow.

 

[GrahamM]

Did you strip out burner and give a good clean? Heat exchanger clean?
Remove flue inspect hatch and clean/inspect flue.
BP sitting stable?
If so would not worry about it too much. As you mentioned strong winds may be causing a bit of fluctuation on your readings.

 

[buckley plumb]

serviced one last wk and had same sinario . stripped and cleaned . burner removed and washed out and cleaned heat ex and flue.was ok 0.0020 until wind blew then went up and down like yours .put it down to the wind effecting the balanced flue.

ant

 

[jtsplumbing]

Cant see the point of putting a FGA in a boiler of this age as long as all other readings are ok and seals etc, is it now a requirment to FGA every boiler ?

 

[mountainman]

Cant see the point of putting a FGA in a boiler of this age as long as all other readings are ok and seals etc, is it now a requirment to FGA every boiler ?

I agree!!

 

[Dotty]

Cant see the point of putting a FGA in a boiler of this age as long as all other readings are ok and seals etc, is it now a requirment to FGA every boiler ?

depends on MI's i suppose.

 

[mountainman]

depends on MI's i suppose.

That boiler was from the era when MI's ran to ten pages and FGA was mainly for commercial appliances.

 

[Dotty]

That's why I don't touch domestic.... too confusing!

 

[Millsy 82]

Cant see the point of putting a FGA in a boiler of this age as long as all other readings are ok and seals etc, is it now a requirment to FGA every boiler ?

Agree only time I will put FGA in a boiler this age is to prove to the customer that the boiler is unsafe due to flame picture.

There is too much reliance on FGA now.

 

[Leo21]

As above forget fga,s on stuff this old. Flame picture, burner pressure. Job done.

 

[GrahamM]

Cant see the point of putting a FGA in a boiler of this age as long as all other readings are ok and seals etc, is it now a requirment to FGA every boiler ?

As mentioned time and time again. You have a tool at your disposal that may indicate more than you can actually see.
Sometime flame picture, BP and checking seals etc. don't tell the whole story.
It is poor practice not to take a few mins to use your FGA on every boiler that has a test point or available termination in my opinion.
I know I am using every tool at my disposal to ensure the appliance is operating safely.

 

[stevetheplumber]

cars before a certain date dont have to meet modern day standards same has to be true for older boilers which were never made to be fga ed

 

[jtsplumbing]

As mentioned time and time again. You have a tool at your disposal that may indicate more than you can actually see.
Sometime flame picture, BP and checking seals etc. don't tell the whole story.
It is poor practice not to take a few mins to use your FGA on every boiler that has a test point or available termination in my opinion.
I know I am using every tool at my disposal to ensure the appliance is operating safely.

Sorry but I think that I disagree with what you are saying about FGAing older boilers ! how do you think we managed B4 we had to have them ? We used our knowlage and experience, Yes ok for new condensing equipment , but relying on FGAs to deside weather an older style boiler is unsafe I think is wrong !! If the service & inspection is carried out as it should be then the need to condem perfectly good working boilers would stop ! and people would not be forced into buying new units that they can ill afford, uesing fear tactics to sell somthing that is not required I think is somewhat underhanded, and is used far to often by Large & small Co just to secure a sale, This reply is not ment to offend its my personal view point.

 

[mountainman]

JTS
I agree with your disagreeing.
FGA and Ambient CO are good and valid tests on an open flued or catalytic appliance, but using modern technology on RS appliances where there is no lawful requirement is IMO pointless.

 

[jtsplumbing]

JTS
I agree with your disagreeing.
FGA and Ambient CO are good and valid tests on an open flued or catalytic appliance, but using modern technology on RS appliances where there is no lawful requirement is IMO pointless.

:iagree:

 

[DirksPlumbing]

I am not wanting to moan but 2000ppm is a potentially deadly dose if taken in over a long period. Or at least can cause all sorts of unwellness including brain damage.

Not to mention the damage to the O2 sensor in your FGA on extended exposure.

 

[jtsplumbing]

Yes he was getting a high reading ! but did he let the boiler get hot ? remember the older boilers took their time to get up to temp ! readings were outside not inside, pointless to FGA these old boilers you will never get the right readings ! just use it for taking Amb CO around boiler to pick up any leakage

 

[Bernie2]

Time for Gas safe to come up with a definitive answer.

 

[DirksPlumbing]

... did he let the boiler get hot ? remember the older boilers took their time to get up to temp ! readings were outside not inside, pointless to FGA these old boilers you will never get the right readings ! just use it for taking Amb CO around boiler to pick up any leakage

I agree on the point that these are not easy this way and there is still no requirement AFAIK to FGA them. But anything above 500ppm can potentially harm people. The neighbour might be sitting in the garden next to it or the kids play around it. At least the customer should be made aware of this.
I assumed by taking various readings that the boiler must have run for a good while.
Surely cancer or brain damage does not sound like the things you want to do to your next or to yourself. Even if it is legal.

 

[DirksPlumbing]

Time for Gas safe to come up with a definitive answer.

Good point. But even then I would make the customer aware of the risks.

 

[jtsplumbing]

Good point. But even then I would make the customer aware of the risks.

Then they think you are trying to sell them a new boiler ! normal reply well its been ok for the last `X` amount of years ! as long as its working that is all they care about !! Still they could go to J Ball and his £17 a Mth boiler.

 

[DirksPlumbing]

JTS
I agree with your disagreeing.
FGA and Ambient CO are good and valid tests on an open flued or catalytic appliance, but using modern technology on RS appliances where there is no lawful requirement is IMO pointless.

Agree on that but the damage is done and the knowledge gained about a potential harm in this case. It is a bit like the lady that had phoned Transco for a smell at her meter. They came and shut everything down. The smell was soon identified as a dead rat a foot below the meter. But because of the smell the normally permissible leak rate of about 2mbar did not apply so we had to rip the whole place apart to get it legal.

 

[DirksPlumbing]

Still they could go to J Ball and his £17 a Mth boiler.

Hmm that is another thing. An ex trainee of mine had been offered fitting for them as well. I have asked him how he then wants to pay his resits of this amount of payments. I hope it is not a con for the customers but the offer was definitely a con for a GSR installer. But someone got to pay for it. If it is not J.Ball or the customer...

 

[DirksPlumbing]

But unfortunately it will hit at least some of the customers as well. There will be no time for explanations, fine tuning, service or often even correcting installation mistakes.

 

[dave1]

Just to clarify then, on an older boiler where it says nothing regarding taking a analyser reader there is no requirement to do so under cpa1?
If say for example, I service a older boiler, check the usual all looks good but then take a reading with the analyser and it's readings are sky high. What actions need to be taken AR? Or would it depend on variables such as where the flue is sited?

 

[DirksPlumbing]

Just to clarify then, on an older boiler where it says nothing regarding taking a analyser reader there is no requirement to do so under cpa1?
If say for example, I service a older boiler, check the usual all looks good but then take a reading with the analyser and it's readings are sky high. What actions need to be taken AR? Or would it depend on variables such as where the flue is sited?

Truthful spoken the answer has been given already by Bernie2.
Even though phone calls like that usually end with the adviser playing the ball back in your corner by telling you that this is at the end your decision and finally your liability. But if the customer calls on gas safe for clarification they tend to back you when it comes to CO and better being safe than sorry.

 

[neily01]

love my analyser but can be an excuse to not do a proper job. remember a l/lords sent to do behind bg who had a few weeks previously "serviced" the boiler. cant remember what boiler, did a fga of boiler had a ratio of about 0.004 producing 600ppm. finally convinced customer to let me do further checks although as the customer kept telling me bg had just serviced! fg ratio correct or not im not leaving a boiler producing 600ppm when it prob just needs a good clean out. a good clean out and a new fan seal later as old one turned out to have broken down 16ppm! there is what is legally right and common sense, lets not let the basics get forgotten

 

[Nostrum]

It's at risk if above 0.008 on a room sealed. No you don't have to do it, but it's that catch 22, if you do it you have to inform customer and recommend disconnecting. Your not in any way forcing the customer to buy a new boiler, it's their choice and if they say no you issue a warning notice and you've covered yourself from any potential come back.

There is no reason why an old boiler should produce high co? They aren't designed for efficiency so excess air isn't controlled. There's tons of free oxygen for a clean burn so CO shouldn't be an issue. If the boilers spewing out co it's because of poor combustion.

No excuse, just because FGA wasn't invented when the boiler was made doesn't mean it's safe to leave it. Would you be happy carrying your kids around in the back of an old escort with no seat belts just because back in the day they weren't fitted, so it must be safe?

Times change and bringing potentially dangerous appliances to light can only be a good thing, yes it's an expense, yes an inconvenience to turn it off but safety is more important in my eyes.

 

[Billy Bob Bob]

It's at risk if above 0.008 on a room sealed. No you don't have to do it, but it's that catch 22, if you do it you have to inform customer and recommend disconnecting. Your not in any way forcing the customer to buy a new boiler, it's their choice and if they say no you issue a warning notice and you've covered yourself from any potential come back.

There is no reason why an old boiler should produce high co? They aren't designed for efficiency so excess air isn't controlled. There's tons of free oxygen for a clean burn so CO shouldn't be an issue. If the boilers spewing out co it's because of poor combustion.

No excuse, just because FGA wasn't invented when the boiler was made doesn't mean it's safe to leave it. Would you be happy carrying your kids around in the back of an old escort with no seat belts just because back in the day they weren't fitted, so it must be safe?

Times change and bringing potentially dangerous appliances to light can only be a good thing, yes it's an expense, yes an inconvenience to turn it off but safety is more important in my eyes.

i can see your point but i also see why you should not stick a fga in a cast boiler,the shale and rough castings in the hex can give very diffrent readings due to manufactering tolerances at the time it was made no fga was needed,now go find a baxi 105 HE stick your fga in the flue,the reading will go to high co,why?because it was not designed to be fga,ed,old boilers dont need it however it does not hurt to use it,it will tell you if its over gassing but it will also give a high reading on some older boilers until we have a standard to work too just do it the way you feel is safe

 

[Doodlebug]

love my analyser but can be an excuse to not do a proper job. remember a l/lords sent to do behind bg who had a few weeks previously "serviced" the boiler. cant remember what boiler, did a fga of boiler had a ratio of about 0.004 producing 600ppm. finally convinced customer to let me do further checks although as the customer kept telling me bg had just serviced! fg ratio correct or not im not leaving a boiler producing 600ppm when it prob just needs a good clean out. a good clean out and a new fan seal later as old one turned out to have broken down 16ppm! there is what is legally right and common sense, lets not let the basics get forgotten

What boiler was this?


Sent from my iPad using Tapatalk HD

 

[neily01]

Cant remember couldnt of been classic might have been a gw. older boiler not a premix remember it was easy enough to service

 

[AmritPedersen]

i can see your point but i also see why you should not stick a fga in a cast boiler,the shale and rough castings in the hex can give very diffrent readings due to manufactering tolerances at the time it was made no fga was needed,now go find a baxi 105 HE stick your fga in the flue,the reading will go to high co,why?because it was not designed to be fga,ed,old boilers dont need it however it does not hurt to use it,it will tell you if its over gassing but it will also give a high reading on some older boilers until we have a standard to work too just do it the way you feel is safe

Hi Gas Man. Just been going crazy on a Baxi 105e with fluctuating CO/CO2 ratios. Did the usual: strip clean hex, burner & fan etc. Vertical flue just within 4 meters length. Can't see any reason for fluctuation, but it does. Feel somewhat happier to read your post.

I always use my fga; it cost enough, why not use it?

Also, I can't see all the flame picture, so may miss something. The fga will back up my visual assessment.

 

[kevin]

Had this problem the other day after fitting an expansion vessel, I had to take flue off this vokera syntesi so did a fga and the readings where through the roof so took the boiler apart cleaned reassembled same thing tested gas burner rates gas rated all fine done my head in then when I put the case back on I heard the fan dident sound just right, after a fga the readings were spot on took the case off again the reading went nuts, tested fan found it was just not getting up to speed intermittent replaced fan job done fga spot on.