Service of the 90% efficient gas furnace part 1

This one is the beginning of a series on servicing the high efficiency gas furnace that ranges from 92 to 97% efficiency. This video is part of the heating and cooling series of training videos made to accompany my websites: www.graycoolingman.com and www.grayfurnaceman.com to pass on what I have learned in many years of service and repair. If you have suggestions or comments they are welcome.
If you are a homeowner looking to repair your own appliance, understand that the voltages can be lethal, the fuels are highly flammable and high pressures are used. Know your limits.

[@Talentman18]

Thank you Gary been watching your videos since 2014 now I’m killing it in service.

[@jevinbrown7402]

Former Army veteran transitioning into HVAC. I'll be graduating from tech school this fall. Your videos help me understand theory and functions more than the classroom. Thanks!

[@grayfurnaceman]

Thanks for the service, GI. And welcome for the videos. GFM

[@stevencantrell2008]

Great video and helpful comments. I'm hoping this gets rid of my elusive 42 error I've been chasing for four years. I've already replaced everything else including the orig. inducer motor with a lightly used original model (now making noise). Fingers crossed this one spins up faster/better to make things happy.

[@TheBoxFort759]

Great video

[@ozzstars_cars]

looking forward to this series of vids

[@JSLEnterprises]

Im just happy its a Trane, so I know exactly what to look for.

[@melvin292]

Great video. Thank you

[@trodriguez362]

thanks for the information also very good video

[@grayfurnaceman]

Welcome. More coming. GFM

[@prestemon]

Your vids are great!

[@grayfurnaceman]

Thanks for the support. GFM

[@richardhaneberg6278]

I love your videos. I can't find part two of this video.

[@hvacrjunky6119]

Great Video!👍😎

[@chopsticks4beginners]

Again, Great Videos...quick question though...I have a 15 yr old Bryant 90plus Gas Furnace (has a recall I just learned from your videos) and it turns off after about 3 hours and wont turn back on (I'm assuming as a result of the flame blow out switch on the combustion chamber cover..It gets reeeaaaally hot to the touch). After it clicks off the blower motor stays on to cool the unit until I turn the breaker off. Does the combustion chamber cover normally get that hot?

[@grayfurnaceman]

No. It is probably rolling out from the blocked heat exchanger. GFM

[@papoloco34]

good video gfm!!!

[@grayfurnaceman]

Thanks. More coming. GFM

[@papoloco34]

waiting for It..👍👍👍

[@mikumiku925]

Love it!!!! 😍😍😍

[@mackseward]

Gary, do you have any videos on oil furnace blowing lukewarm air?

[@grayfurnaceman]

No. I would look for a short cycling issue. Does the burner cycle on and off every few minutes? GFM

[@jevinbrown7402]

With the heating season upon us can you give advice on proper CO testing with a detector? safe ppm and unsafe ppm.

[@grayfurnaceman]

Will be doing some on this issue soon. GFM

[@tat255987]

I have a Ruud 90 plus achiever with a fault code one. Was told the furnace needs to be replaced but Im not biting. Cant the heat exchanger just be cleaned?? Help!!

[@grayfurnaceman]

I believe fault code 1 is ignition failure. That would not normally be a heat exchanger failure. It could be a number of failures. The only failure that would indicate replacement would be if the unit has a mercury actuated control system. Do you have any details on the diagnosis? GFM

[@tat255987]

@@grayfurnaceman I do, tech says " Furnace heat exchanger is plugging up bad, this is causing furnace to go out on pressure switch error and causing high carbon monoxide in the flu furnace needs to be replaced ASAP it will run but only with top door off furnace."

[@grayfurnaceman]

@@tat255987 That could happen. However, the diagnosis does not sound right. There is a little too much sales there. I would get a second opinion. GFM

[@kylefaubert7768]

are you interested in making a video on commercial refrigeration? I'd like to learn about the controls such as prv, head pressure controls and such

[@Nick1814]

What do you do if there is rollout? Replace the heat exchanger?

[@grayfurnaceman]

Rollout can be caused by several problems. One, of course, is a heat exchanger problem, The heat exchanger could have a crack or a blockage. Burner alignment or dirty burners could also cause this. Gas pressure could also be the problem. Incorrect orifices could cause this. GFM

[@trodriguez362]

what would cause the flames to kick back or roll out dlightly when the burners come on before the fan comes on . What can cause that and how can it be corrected

[@grayfurnaceman]

Depends on how much they rollout and when. If the rollout is about 1/2 second when the burner first comes on it is normal. If it rolls out and rises up the front of the furnace, the heat exchanger is probably plugged. If it rolls out when the fan comes on the heat exchanger is probably cracked. Hope this helps. GFM

[@av_rob79]

Hey I have this furnace (or one very similar) and the cover was off. I'm attempting to put the cover back on but not entirely sure if I did it right. There is about a 6 inch gap above the cover where the duct is and maybe a 4 inch gap at the bottom. I'm not sure if there should even be a gap at the bottom or if it should be flush.

[@grayfurnaceman]

Some furnaces have a top cover that does not cover the entire front so it may be normal. GFM

[@randydolin5883]

clean the drain

[@TheBoxFort759]

Great video