[tedkidd]

If the HO stands around and watches. I put them to work! "Hand me that, hold the flashlight"!!!!I love it!!!!:grin2:

+2

 

[hotandcoldair]

New guy at my last job: pulls out the furnace high limit switch because the unit kept shutting off while he was trying to measure the delta T. Homeowner comes in and starts to talk and new guy forgets. Next thing you know the evap coil is on fire (from all the crap built up, also the cause of the short cycling) smoke is pouring out and the kid is paralyzed with fear. Fortunately there was another tech there installing a water heater (he had just quit our company - great) and he shut off the gas and broke out a fire extinguisher. The house was way high dollar and we had to put up the homeowner and his family in a ritzy hotel for one week while they cleaned the smoke damage. Two weeks later the kid totalled a truck and they fired him. Homeowner got to keep his job...

 

[tedkidd]

Intense story!

pulls out the furnace high limit switch because the unit kept shutting off while he was trying to measure the delta T.

Uh, im not following. Why would you want delta t on a short cycling unit?

Where would one find pulling high limit recommended? Or was this an example of obsessing without thinking big picture.

 

[mason]

Intense story!



Uh, im not following. Why would you want delta t on a short cycling unit?

Where would one find pulling high limit recommended? Or was this an example of obsessing without thinking big picture.

I think he's talking about temp rise. Measuring the return and supply to see of it meets temp rise on the unit label. If you literally pull the limit out it would allow you to insert your static probe after the blower and before the coil to check for a pressure drop across the evap coil causing the heat exchanger to overheat from not moving enough air across it. This applies to a split system gas furnace but would not be used on many packaged units.

 

[J-thetechwizard]

I didn't realize the air coming off a standard furnace (without the high temp limit shutoff) could actually start evap crap on fire!!
I was assuming the air was not thathot for this exact reason.

Does anybody have the average temp. of said heat exchanger situation???

 

[hotandcoldair]

I can't say for sure on this furnace but I have seen 170F plus at the plenum. Not sure why this one ignited - cat hair? Belly button lint?

 

[zw17]

When I have a service tech, plumber, electrician etc. at my house or at work, I'll ask for an update and see how things are going, make sure the little details look OK, then I leave them alone. He** if nothing else, it's usually a T&M job so they are on my clock and me standing there sure isn't making it get done faster.

I find it hard to look over my own shoulder and get any amount of work done.

I also find my service tech, plumber, electrician is always drinking on the job while working around the house.

 

[tedkidd]

If you literally pull the limit out it would allow you to insert your static probe after the blower and before the coil to check for a pressure drop across the evap coil causing the heat exchanger to overheat from not moving enough air across it. This applies to a split system gas furnace but would not be used on many packaged units.

Ah! Thanks.

So it's common practice to pull the limit to use the hole because there is no other access before the coil.

I thought he actually pulled it to avoid it's tripping. That seemed scary/funny on the level of the live swap gas valve story.

 

[hotandcoldair]

No - he pulled it to keep the unit from tripping. This was the NEW guy (not a new hire a trainee). We didn't get the chance to talk about static pressure...he was still working out static cling.

 

[Snapperhead]

I had a homeowner show up with his own tools once...I stood over his shoulder and made him work....lol

Actually I did that once as well ... handed the guy my coil cleaner and asked him spray this coil down while I go get something.

Come back to find him coughing away . He walked off still coughing and I never saw him again lol

 

[mason]

Ah! Thanks.

So it's common practice to pull the limit to use the hole because there is no other access before the coil.

I thought he actually pulled it to avoid it's tripping. That seemed scary/funny on the level of the live swap gas valve story.

It appears he 'pulled' it to prevent it from tripping but yes many techs will pull out the limit for static probe insertion or to snake their camera to view the underside of the coil.

 

[akelesis]

when a customer is watching me i always ask if i can have a cold glass of water or just walk back into my truck for 2 mins and go back and see if he is still there. usually they are not. but sometimes they are. ya like the other guy said i take longer and bill for that time.

Dont you enjoy the times where the customer is looking over ur shoulder and you discover a crack. you need a new furnace Sir. that gets him steamed for at least a half an hour. laf.

 

[Snapperhead]

Dont you enjoy the times where the customer is looking over ur shoulder and you discover a crack. you need a new furnace Sir. that gets him steamed for at least a half an hour.

Yep , seen that movie as well .... the lady was like WHAT ! ? I dont have any money for a furnace , let me see that crack , where did you see it , let me see it , i wanna see it , how can that be cracked , how big could it be , thats not That big

Sorry lady , there are 3 cracks , 2 inches long, and its blowing the flames out the front trippin the sensor , im shutting it off.

 

[Pete954]

I just tell them if they are gonna watch they need to stand back and not approach the unit the power is on and has moving parts. Can never be to safe.

That and I had homeowner walk up while I was bent down and stick his hand right on the contactor in a rheem unit. He got back inside pretty fast.

I had to smack a lady's hand away from an open breaker panel once. Pointed to it with my sharpie and she went to touch it with her bare hand!!!! I can picture the call, "umm hey small problem here, I killed the customer"

The only thing worse than the customer over your shoulder is the boss over your shoulder. Although I once handed him tools and told him to show me how "easy" it was. Half an hour later he handed 'em back saying "you git this right?". Which i did. :grin2: