Things used to be so easy when working in this business back in the day. When carrying tools for some old timers, I remember some replacing an air filter and kicking the furnace while saying"Yup, still here!" Maintenance these days, for great reason, has taken a more efficient operation mentality, mainly because energy prices have started to affect our wallets. These days, 68% steady state efficiency oil boilers and gas furnaces with high carbon monoxide readings mean something. But, does it necessarily mean we must replace the furnace, boiler, hot water heater, etc.?
I heard a situation a couple weeks ago where a representative of a local gas company, whether or not he was a subcontractor I cannot be sure, completed some maintenance on a gas boiler that he ended up shutting down due to a high CO reading. Most building analysts know that 26-100 ppm CO (in the flue, at steady state) means repair is necessary (see Combustion Safety Test Procedure, BPI.org), and to call a heating professional. So why did this tech shut down and tag this boiler for replacement? Was it actually a sales tactic?
High Carbon monoxide readings tend to point to what I like to call "unbalanced combustion". You see, it could be due to lack of combustion air, too much gas, or too much excess air (not my blog, please keep clicking!). No matter how you slice it, the combustion process is out of balance. I have seen high CO readings for draft inducers failing, secondary heat exchanger condensate drains clogging, improper manifold gas pressure, incorrectly adjusted draft dampers, you get the idea! None of these reasons mean the equipment has to be replaced, but the recommendation could be made.
The boiler I started talking about earlier had a manifold gas pressure twice the recommended value. There was too much combustion air due to a lack of understanding and/or measurement. Since he took the readings, I doubt it was the latter. Looking at the flame on a 90%+ AFUE appliance will never be a justified reason to crank up the manifold gas pressure. If you cannot measure with a combustion analyzer, or even a manometer, at least clock the gas meter before you start creating high CO2 and CO outputs. You are the professional and the homeowner is paying you for the expertise. Please, don't recommend replacing a boiler your company may have installed just a a couple years ago!
http://excessair.blogspot.com/2013/01/high-co-reading-now-what.html...

Views: 1182

Comment

You need to be a member of Home Energy Pros to add comments!

Join Home Energy Pros

Comment by tedkidd on January 10, 2013 at 9:26am

I can't answer how much of red tag was a sales tactic, but search CO poisoning on google news, or create a news alert and you'll see news reports of deaths and people hospitalized daily.   

Any device disconnected from the flue is dangerous.  That means any natural draft appliance, because they are all disconnected from the chimney they supposedly vent through.  

Here's a great blog by David Richardson on the subject: http://bit.ly/davidrDrafthoods 

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Home Energy Magazine posted a discussion

Let's Talk Gender

It’s no secret that home performance is a male-dominated industry. Attend any industry conference…See More
2 hours ago
Mark Rogers added a discussion to the group Energy Auditing Equipment for Sale, Trade or to Purchase
Thumbnail

Retrotec Blower Door Kit $1800

Retrotec Blower Door Kit complete with:DM2 Mark II digital manometer & automated fan…See More
3 hours ago
Maria Lacey replied to Jamie Kaye's discussion Flickering LED lights
"I think the tendency is to look at lamps (light bulbs) as though they're the same if they all…"
3 hours ago
tedkidd commented on Scott Mellberg's blog post Lessons from Energy Efficiency Advisors: Getting Homeowners Onboard with Home Performance
"Absolutely agree Ben, "How much do I use, how much do others use, and what is my reasonable…"
4 hours ago
Profile IconTauran Ivall, Alex Burnham and Annika Brink joined Home Energy Pros
5 hours ago
David Eakin replied to Jamie Kaye's discussion Flickering LED lights
"I also thought that, but I tried to put a CFL in the A-19 outside fixture at my…"
5 hours ago
Ben Jacobs commented on Scott Mellberg's blog post Lessons from Energy Efficiency Advisors: Getting Homeowners Onboard with Home Performance
" I believe a major problem of government, of energy utilities, and home energy efficiency…"
6 hours ago
Jill Lindman posted an event

EEBA Houses That Work Education & Training at Johnson County Administration Building

August 22, 2014 from 8:30am to 4:30pm
About the SessionsIntro to Houses That Work: In this session participants learn how the many…See More
6 hours ago
Glen Gallo replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Title 24 requires whole house fans in zones 8-14 in the prescriptive path only. With many…"
8 hours ago
Jenn Saunders replied to Jenn Saunders's discussion iEnergyApp: Quickly generate professional reports for homeowners and get more contracts!
"Hey Tom, You are most welcome.  iEnergyApp is not free, but it is reasonable and pays for…"
8 hours ago
Jenn Saunders posted a photo

Automatically Generate Clean Simple Reports for Homeowners

Stop spending hours cropping and resizing images, formatting and reformatting a Word document to…
8 hours ago
Eric Sperline added a discussion to the group Energy Auditing Equipment for Sale, Trade or to Purchase
Thumbnail

Beware ebay seller "supermomofps"

I bought a blower door system on Ebay from "supermomofps"  The item was never sent and…See More
8 hours ago

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service