Hello all,
Taking the courses.
I’m inspecting a high efficiency natural gas furnace for the HVAC inspection assignment. There isn’t a shut off switch at or near the furnace. None at all. The furnace isn’t even labeled at the breaker panel. I wanted to take the doors off to complete the inspection and follow procedures as Jim does in the instructional video. Should I sight no shut off near furnace in the report, wasn’t able to take the doors off to check start up? Even if there is a door shut off switch on this model, how would i go about doing a start up test?
Hoping for some guidance here.
Thank you,
Mark
Is the panel within sight of furnace? That would count as the service disconnect. In Oregon it’s super-common to have a panel and furnace in a garage so no cutoff switch.
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Yes the panel is in sight, but unfortunately they did not label the furnace at the breaker panel.
Usually the door cutoff switch is in sight when you open or remove the door. Sometimes it’s hidden in one of the fastener holes. Best bet is get the model # and most likely you will able to find the owner\service manual online which should indicate where the door switch is.
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Thanks Thomas.
If this model does have a door switch, when I want to perform a start up test with doors off could I use this switch instead of a shut off switch (there isn’t one), as well the furnace is not labeled at the breaker panel.
Yes, if you can locate the switch. The furnace will not activate if the switch is not pushed in or pressed. You simply press the switch and the system should turn on. You might need a screwdriver or something to press the switch depending on location, and you will have to keep it pressed during your time inspecting it.
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This is good to know, as i don’t want to try and follow wires into the unmarked breaker box and accidently trip the wrong breaker.
Thanks again
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You are bordering on exceeding the SOP.
Does the Internachi Education Course instruct you to perform this test in that manner, or at all?
Are you performing a diagnostic test, or operating the unit only with normal controls?
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What is a start-up test?
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Not speaking for him, but wouldn’t “starting” or activating a furnace to see if the heating elements turns on and the blower kick on be considered as such?
Is their a different term that should be used?
I always operated the HVAC from the thermostat and it either operated as intended or it didn’t and that is what my report stated…if it was old rusty and nasty my report recommended service and evaluation from a qualified HVAC tech…
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Me neither… but I suspect it is when the furnace is “started up” while watching the Burner Chamber to observe the flame reaction.
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My thinking too, but as Jim stated, it either works at the thermostat, or it doesn’t! 
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Thus my query above.
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I have no problem with those who know what to look for, such as a flame reaction. But when you ask about the panel door safety switch or other means to control power to the unit such as following wires into an unmarked breaker box, I want to know what he considers a start-up to be and how he would evaluate it.
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Maybe he will reply to you and and satisfy your inquiry…maybe he won’t. 
What Thomas and Jeffrey said - fan - cylinder click- burn chamber. this as shown in the Video- Inspecting a heating system with Jim. Does the video exceed the SOP? I did not hear in the video that it was exceeding the SOP. He also takes a picture of the data plate inside the furnace which he says is good to do in case a new unit is put in down the road and there’s a problem with it he has proof that he inspected another one. I would sooner just check it with the thermostat and not do this if it is exceeding the SOP.
Hi Brian I replied below - thanks for taking the time in helping me with my queries.
The service switch or kill switch is separate from the blower door safety switch. If there is an electric panel in sight with the furnace’s breaker then you are good. In your case, the breaker is not labelled so report that as a deficiency.
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Thanks Lon,
Am I exceeding the SOP if I’m taking off the cover plate and checking the operations - fan - cylinder click - gas ignite - burn chamber etc…