Question for Centarl Heating / Boiler Engineer

[EliTom]

Hi

Just had my 12 year old boiler service. It has not been serviced in the last few years so thought it better get done.

Anyway Corgi guy who came out first checked the gas supply - all OK

then did a quick visual inspection of the boiler - all OK

Then he did a combustion analysis using a Kane 455 combustion flue gas analyser and said the boiler was running perfectly and the flue analysis was one of the best he had seen in a long time so there was no need to do any strip or cleaning of the boiler.

So my question is from the results below, do these look good and are they too good to be true for a 12 year old boiler.

I guess my real question is has he given a good set of data so that he can just finish early on a Friday afternoon without stripping / cleaning anything, or is it possible that my 12 year old boiler is still in perfect working order???

Boiler is a Ariston EuroCombi SX20MFFICE

Fuel Nat Gas

O2% - 12. CO2% - 4.6 CO ppm - 8 Flue degC - 102.2 Inlet degC - 23.3 Nett degC - 78.7

EFF (C) - 93.3 Losses - 6.7 XAIR % - 158.0

Cheers

EliTom

CO/CO2 - 0.0001

PRS mbar - 0.60

[Andrew Gabriel]

If this is a non-condensing boiler, then it hadn't really warmed up when the test was done (I would expect something 150C-250C). If it's a condensing boiler (seems unlikely for 12 years old), then it must be set very high.

This figure is meaningless as it's not warmed up (unless it's a condesing boiler).

^^^^^^ That's the key one (CO to CO2 ratio). Anything below 0.008 is normally held to be fine. You are 80 times better than that.

I just got 0.00023 from a 17 year old Potterton Profile. I did service it last year which was first time in 7 years (which it didn't need, but I was getting concerned at not opening it up for that long).

[EliTom]

Thanks Andrew

Yes it is a non-condensing boiler.

And yes it did not have more than five minutes to warm up - the heating has not been on in months!

So is it reasonable to say that is the C)/CO2 ratio is good that teh boiler do not need opened up and cleaned?

Corgi guy said it should have another 5 years or so of life left yet. So I can delay the inevitable cost of replaceing it with a condensing boiler for a few years yet!

EliTom

[Andrew Gabriel]

Like I said, I get concerned at not opening the boiler occasionally, but that CO/CO2 ratio indicates the combustion is operating very well. It's possible he might have identified some other fault such as an early leak in the heat exchanger if he'd actually looked inside.

The CO/CO2 ratio doesn't tell you anything about how much longer the boiler might last, only if it isn't burning optimally. The things that boilers usually die of don't normally affect how well they're burning gas, until right at the last moment!

[YAPH]

Yup, that's a good figure and if it were me I wouldn't want to open up the boiler, disturbing the seals etc, if I could say from a CGA that it's burning OK. Most times one opens up a room-sealed boiler it's clean inside and nothing much to do except put it back together again.

One still needs to check that the safety controls (that ensure it doesn't let gas through with no flame) are working OK, of course.

[EliTom]

OK seems reasonable. I did actuallly replace the DHW heat exchanger at teh end of last year and also cleaned the main heat exchanger whilst the water side of the boiler was stripped down, so I know that the combustion chamber is clean.

I know he did check the gas side for leaks and also had a meter of some kind on the gas meter, I guess for the operating pressure. The boiler is the only gas appliance on the meter. He also did some timed reading of some description and has recorded the operating pressure and heat input on the inspection report.

I also did see him check all the seals on the boiler for poison gases with a sniffer.

So maybe he did have an easy job and made some quick money !!

[Terry Fields]

No! No!

You must rush out straight away and buy a complete new system for thousands of pounds in order to save the planet from global warm...er...climate ch...er....something or other.

Why, only within the last day or so we've had the Beijing Olympics ceremony and a Russo-Georgian war to offset, so get out there buying and do your bit to save the planet.

Plus, of course, all the hidden benefits of supplying an income to control people, inspection people, certificate-issuing people, certificate-inspecting people, cetificate-certifying people, regulator people and their all their health-an-safety people, human resources people, ethnic diversity monitoring people, carbon-footprint monitoring people....

Get out there buying!

[tony sayer]

How can this alter?, after all if there is sufficient air supply and exhaust then what's to go wrong with the actual gas burning??......