The attic is well-ventilated but probably could be improved. Both gable vents are on the rear side of the house…no cross-draft
Ventilation air never planned on a furnace in that space.
1 Like
There is the problem with dust and the open flames in the attic. Any movement around the furnace with the cover off can send dust into the flames and you get very yellow or orange flames. Have to wait a while for the flame colors to stabilize, but even then it is difficult to get all blue flames completely without even a speck of yellow or orange.
3 Likes
Thanks Yu. I am always on the lookout for indicators of poor combustion. Many of our furnaces in my area are in attics and I see what you described. Looks like we can cross that off the list in this case.
1 Like
It’s the angle of the dangle giving a false image 
2 Likes
good info for him.
1 Like
It appears air quality in attic is not good. Yield on caution, note detectors and your exposure to recommend further testing to possibly issues with furnace ventilation.
1 Like
Here are my thoughts - Natural gas is odorless and tasteless, the gas company actually adds a harmless substance called mercaptan which gives the gas it’s rotten egg smell to help in detecting leaks. The gas company could be cutting corners or the mercaptan concentrations could, due to travel distance, be so low as to go unnoticed.
There have been several recent gas explosions that have leveled structures and taken lives because of gas leaks that were not detected due to this problem.
As natural gas continuously leaks into your home or attic, it can affect your sense of smell and displace oxygen, causing breathing difficulties, headaches, and nausea. If the leak is in the attic, it may only effect you when in the attic and not be entering the house.
I would definitely call this out as a SAFETY issue and have the gas company revisit and retest especially in the attic area where you detected the issue.
2 Likes
As a general comment, it sounds like you already did this, but for less experienced HIs reading this thread, I recommend reporting what happened to the client. It will probably be a lengthy essay, describing what happened and your concerns. Particularly, since you re-experienced symptoms on your revisit. You may not be very susceptible, but a member of your client’s family might be more sensitive to whatever, if anything, might be there.
If someone says that you may be unduly raising alarm, I agree that there is a risk of that, but if you had smelled a fleeting whiff of sewer gas where you shouldn’t, wouldn’t you mention that in your report? Sometimes, things like this require investigation by an environmental hygienist.
4 Likes
I don’t believe anyone has suggested this: First Call The Natural Gas Utility Company Now!
This is Why!
You are getting a Very High Explosive Gas Reading in the Attic but No Smell/Odor… Natural Gas (as well as Propane) is usually Completely Odorless up till the time the Utility Company adds “Mercaptan” which they do to alert you that you have a gas leak. It very well could be Natural Gas leaking from a Supply pipeline from a well. Before The Mercaptan is added. Not the Residential Service line.
Natural Gas is lighter than air and that may be why you are only getting the reading in the attic But No Odor. And Why You in the Attic was the only one feeling symptoms. (next time let the agent be the Canary)
My Niece and her family lived in the same neighborhood that killed a family in Firestone Colorado because of this exact scenario. They had no warning as there was no Odor… Colorado Announces $18.25 Million Fine For 2017’s Deadly Firestone Explosion | Colorado Public Radio.
4 Likes
The OP said “The gas company paid a visit but said there was no gas detected (so they say).”
1 Like
OK, here is the final update: The water heater 3 inch flue did not go entirely all the way to the roof as expected. The 3 inch flue extended 18 inches into a 5 inch 2nd combustible barrier flue which was extended all the way to the sheathing. The roof penetration had a 3 inch flue with a proper cap. This flue extended about a 12 inches into the attic inside the 5 inch flue. The problem here is that there was a missing 5 foot section of the 3 inch flue. Since the exhaust looses bouncy in the 5 inch flue the CO dropped down into the attic floor. When I inspected the furnace I was on my ladder at the level of the layer of CO in the attic…This is how I got sick. When I tested the attic for CO later in the day at the day of the inspection the CO had already exhausted with the open attic hatch. The gas detector is still a mystery. The flue was properly replaced yesterday. All good, thank you for all your help! Much appreciated!
7 Likes
Good news and good job!
4 Likes
Wow, good find Bill, especially for your clients. I think it’s fair to say you’re going to be the topic of many of their future discussions, especially when family & freinds are looking to purchase a new home.
4 Likes
What a wonderful job you performed for your clients!
2 Likes
As JJ pointed out, your Klein ET-120 is a combustible gas detector- and not a combustion gas detector. Just a wild card thought: your meter may have been picking up some traces of methane (or other gas) that may be latent in and off-gassed by Chinese dtywall. You noted that the home was built in 2008, which is about the tail end of the Chinese drywall fiasco.
1 Like