ok so i do commercial hvac and well inspecting commercial equipment is fairly easy...dont do alot of resi work but the old furnaces was a visual inspection of the heat exchanger...how do you check the new heat exchangers when you cant even see in the new ones...no one can give me a clear this is how you tell if their cracked....so how are you guys doing it?
inspecting new furnaces
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Doesn't tell you if its cracked or not. Since the inside of the heat exchanger is at a negative pressure.
as beenthere said,there are alot of different inspection cameras to choose from,pull the blower for a visual of outside of heat exchanger, and a combustion analysis of the flue gas also....these are methods i use along with observing flame after blower comes on,.....there are other methods also,but these are the ones that i use the most it seems like.
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How often do you use the combustion analysis gear?
If I am to do an official inspection of the h.e., I would at least pull the blower and/or open the evaporator coil. Since I have a sea snake, and an impact drill, I will pull out the burner assembly as well. The s.s. is an investment, but it's worthwhile.
I you want to keep it simple, you can pull out the limit switch and use the sea snake there, and take a peak through the burner ports, but I wouldn't declare that as an official inspection of the he.
If I am to do an official inspection of the h.e., I would at least pull the blower and/or open the evaporator coil. Since I have a sea snake, and an impact drill, I will pull out the burner assembly as well. The s.s. is an investment, but it's worthwhile.
I you want to keep it simple, you can pull out the limit switch and use the sea snake there, and take a peak through the burner ports, but I wouldn't declare that as an official inspection of the he.
again i am asking about new furnaces...where the heat exchanger is not at all visable...inaccessible to put a smoke bomb...without taking the whole thing appart what are you looking for in the results of the co test if it were cracked?
Watch for the CO to go down(sometimes it will go up)when the blower comes on. Also watch for the O2 to go up when the blower comes on.
These are indications of a crack or hole. But not a 100% there is one.
,there are certain parameters that the co level must fall under....
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My supply house has a kit which they want to get rid of. They offered me a good price, but at this time I can't pull the trigger. None of the outfits I used to work at ever used them or hadone for that matter. I certainly wasn't ready to shell out my money. However, now it's Flash time. Do you think they are a "must have" tool?. I primarily work on nat gas and electric equipment.
Absolutely TRUE. CO burns blue. You cannot tell if you have CO by looking at the color of the flame.
Dr. Thomas Greiner, Iowa University, would display lots of photos during his CO seminars. Some with monoport burners with yellow flames, less than 10 PPM. Some linear burners with doctored orifices and only one unaltered one. The burners were numbered and he would ask people to raise there hand for the burner that was burning the least amount of CO. He said the results would run less than 10 percent of the attendees would guess the correct burner. And that is why you need testing equipment. Period
primarys you basically have to look at,cut hole in plenum and inspect.or if rollout switch tripped its a good indication of trouble..now secondary x changers can pretty accurately be diagnosed by inserting co probe in exhaust vent outside,anything over 100 ppm i'd be pulling vestibule plate off for a closer inspection ..
LCD is too small:whistling
The display does leave a bit to be desired. But, its large enough to see a crack.
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