Quickly Testing Gas Furnace Safety/Limit Switches!

In this HVAC Training Video, I show how to Quickly Test Gas Furnace Limit and Safety Switches such as The Flame Rollout Switch, Thermal Limit, Pressure Switch, and Flame Sensor. Safety Limit Switches can be Tested using a Multimeter and Measuring Electrical Resistance or Voltage! Supervision is needed by a licensed HVACR Tech while performing tasks as Experience and Apprenticeship garners Wisdom and Safety.

Tools Used In The Video

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our Related Videos/Articles

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our HVACR Educational Books, E-Books, Workbooks, Cards, Posters, and PowerPoints:

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our HVACR Online Resources!

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Tools Used in Our Videos!

Support the Channel by purchasing tools through TruTech Tools!
Save 8% at checkout using code "acservicetech"
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Follow Us On Our Social Media & Podcasting Channels!

▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
⚠️ Disclaimer:
Information in this video is intended for educational purposes only. Any work related to the topics in this video should be performed by licensed technicians or by apprentices under the supervision of licensed technicians. AC Service Tech LLC is not responsible for any possible damages or injuries caused by the use or misuse of any information provided. ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
#hvacr #hvacr #hvactrainingvideos #hvactraining #hvactraining101 #acservice #acservicetech #limitswitch #switch #furnace #gasfurnace #rolloutswitch #pressureswitch #flame #rollout
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Shop through Amazon! Your Purchases through Amazon provide a means for channels such as mine to earn advertising fees from all purchases after clicking through. Prices are the same as normal.

[johncarcamo]

Seriously you did better than my gas furnace teacher.

[TrollinTheInterwebs]

I like watching your videos, keeps me from getting rusty.

[aaronr]

I wish there was someone like you to explain commercial boilers

[vetdadcubby]

Simple, effective and professional!! Great job sir!

[ShelterG]

I would like to add on more method. Measure voltage between limit connectors. If O volt means no voltage drop and limit is good. If 28 volt means open circuit - bad limit.

[tytig]

I freaking love your videos, they make my life easier. Thanks!

[izzymoney]

I like to say Thanks for a very well done video this is something the new guy can benefit from bye learning a simple way of doing things keep up the good work 😎

[RayRay-nbtn]

Great video on gas furnace safety switches. Haven't been commenting lately. Been busy with friends Sprint car racing. Season ended so back to the grind again. Thank you for the videos. Be safe.

[jimmysegovia]

thank craig for sharing! all your lessons are really awesome! i have been watching and learning from the start with your videos thank you so much for sharing.

[mikimiki]

Great video
Sonic you reading voltage on switches. That means switches are good

[luiselizalde]

As always excellent explanation., Thanks.

[johnnynguyen]

Is it on specific furnace that you have power across these safeties while the furnace is idled? (Power is ON but no call for Heat)

[Sportsbook-Robbery]

I have a Luxaire older model - I have decent knolwedge from troubleshooting this furnace over the years . I was having trouble remembering what i did a few years ago to get it running correctly. I had to change and fix a few different sensors, limit switch & a Capacitor for the blower motor. basically all the stuff you just went over.. I came across your video.. quick easy and right to the point. quick refresher coarse . I got a limit switch issue I think ( 4 Blinks on my modle) Ill go test them now.. thank you.... Quick question if you see this "OL" that means its bad the ones with the button in the middle/ they should read 0.00 right ? ohms

[robertcherry]

What is the best way to test a high limit switch while in furnace, to prove what temps it is opening and closing at?

[bauhnguefyische]

Always a simple explanation here on how ‘hopscotch’ works with a electric meter.

[T-Bone-]

I've been trying to understand which switchis my Limit Switch, so many videos showing the Rollout Switch as the limit switch! Finally, someone who clarifies what is what. The Limit switch I have is on the back wall, any time I put my thermostat to Auto, it will not turn back on after it turns off to regulate temp. If I keep it set to ON it seems to be fine (all winter).. Any suggestions?

[Millennmify]

Showed me how to test the switches. Found that the thermal limit switch was open showing no ohms. Replaced switch and Goodman furnace works again.

[wxfield]

Why are you using the red lead for your ground?

[RC-udhh]

Wow you blew through that lesson! Just throw this novice right into the furnace fire and repeat. 😆

[Karnol]

Are all gas/ propane low voltage systems common connected to the ground?