Top 4 Reasons Why a Gas Furnace Short Cycles! HVACR Service Call Troubleshooting Tips!
Vložit
- čas přidán 26. 07. 2024
- In this HVAC Training Video, I discuss 4 Main Reasons Why a Gas Furnace Short Cycles and Won't Stay Lit. There are many problems that can cause a Short Cycle. During a No Heat Service Call, keep in mind what could be affecting the component that is Tripping. Supervision is needed by a licensed HVACR Tech while performing tasks as Experience and Apprenticeship garners Wisdom and Safety.
Tools Used In The Video
UEI DL479 Multimeter With Temp Sensor amzn.to/2jtsUbJ
Magnet Jumpers- amzn.to/2PyKPQZ
Alligator Jumpers- amzn.to/2PxqJXn
UEI Digital Dual Manometer - amzn.to/2CWC6BD
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our Related Videos/Articles
• Furnace Flame Sensor T...
• Gas Furnace Flame Rod ...
• Gas Furnace Spark Igni...
• Gas Furnace Spark Igni...
• Troubleshooting the Fu...
• Thermostat Wiring to a...
• Heat Pump Thermostat W...
• Thermostat Wiring Diag...
• Gas Furnace Heat Excha...
• Gas Furnace Troublesho...
• TOP 10 Reasons Why the...
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our HVACR Educational Books, E-Books, Workbooks, Cards, Posters, and PowerPoints:
All Our Educational Products on Our Site: www.acservicetech.com/store
All Our Educational Products on Amazon: amzn.to/48pDd82
Mini Split Book and E-Book on Our Site- www.acservicetech.com/mini-sp...
Mini Split Paperback on Amazon- amzn.to/3ytHJSs
Mini Split Paperback on TruTech Tools- www.trutechtools.com/BooksGui...
Refrigerant Charging Book and E-Book: www.acservicetech.com/ac-book
Refrigerant Charging Paperback on Amazon: amzn.to/46xTeHf
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Our HVACR Online Resources!
Our HVAC Calculators: www.acservicetech.com/hvac-ca...
Our Newest Articles: www.acservicetech.com/articles
Try our HVAC/R Quizzes! www.acservicetech.com/quizzes
Our Other Resources: www.acservicetech.com/resources
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Tools Used in Our Videos!
Tool Links on Our Site: www.acservicetech.com/tools
Our Tool List on Amazon: www.amazon.com/shop/acservice...
Support the Channel by purchasing tools through TruTech Tools!
Use this link www.trutechtools.com/?aff=8
Save 8% at checkout using code "acservicetech"
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
Follow Us On Our Social Media & Podcasting Channels!
Patreon: / acservicetech
Facebook: / acservicetech
Instagram: / acservicetech
X: / acservicetech
LinkedIn: / ac-service-tech-llc
Tiktok: / acservicetech
Spotify: open.spotify.com/show/74KXLz5...
Apple Podcasts: podcasts.apple.com/us/podcast...
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
⚠️ 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 #oil #gasfurnace #shortcycle #furnace #hvaccompany
▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬
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.
The E-Book and Paperback at our Website: www.acservicetech.com/the-book
The Paperback at Amazon: www.amazon.com/shop/acservicetech
Support the Channel- www.patreon.com/acservicetech
Tool List- www.amazon.com/shop/acservicetech
For those that are looking for the tools used in the videos: (Linked Below)
Related Videos:
Thermal Limit Troubleshooting- czcams.com/video/NHoFL8z5zGE/video.html
Top 10 Pressure Switch Problems- czcams.com/video/bY6QcnlbutIP/video.htmlressure
Switch Troubleshooting- czcams.com/video/v9QWIr9TIVUC/video.htmlleaning the Condensate Tubing- czcams.com/video/guf3TESb3V0/video.html
Pressure Switch testing and Replacement- czcams.com/video/6P6r6POGHDcH/video.htmlow
The Pressure Switch Works- czcams.com/video/9DAEZvkyO9A/video.html
Why The Pressure Switch Wont Work While the Condensate Drain is Clogged- czcams.com/video/XKAyznghlroU/video.htmlsing
The SDMN6 to Test Pressure Switches- czcams.com/video/mKtGL8NJ58Q/video.html
ECM Blower Motor Testing: Make Your Own ECM Tester- czcams.com/video/lKsIgjEJDII/video.html
X-13 ECM Blower Motor Testing- czcams.com/video/SamEuSzvYbEE/video.htmlCM
Variable Speed Blower Testing- czcams.com/video/locNv9WsanA/video.html
10 reasons Why The Blower Motor Won't Turn On- czcams.com/video/T5j4Q8Zp_qk/video.html
4 Reasons Why the Blower Motor Won't Shut Off- czcams.com/video/wX3hCqwUjkEW/video.htmlhat
Type Of Blower Motor Do I Have- czcams.com/video/EHwTZFvv-2Q/video.html
240 volt PSC Blower Motor Fan Speeds-czcams.com/video/5GITgsRmSZ4/video.html
How to Tell the Difference Between Blower Fan Motors- czcams.com/video/EHwTZFvv-2Q/video.html
Gas Valve Troubleshooting- czcams.com/video/euUrufn6AsIC/video.htmlombination
Gas Valve, How it Works- czcams.com/video/7m5ZDvOoVwU/video.html
Smart Valve Troubleshooting- czcams.com/video/qjrrXmLlLRc/video.html
750mv Thermopile and 750mv Gas Valve- czcams.com/video/riaN_j5tmX4/video.html
Furnace Flame Sensor and Rectification Troubleshooting- czcams.com/video/LtfghUYfl-4H/video.htmlow
Flame Rectification Works- czcams.com/video/kfQ2ivr4gSw/video.html
Single Rod Spark Ignition and Flame Rectification- czcams.com/video/GNYdOIvWyyk/video.html
Two Rod Spark Ignition and Flame Rectification- czcams.com/video/dUFcVJXJ8Vg/video.html
Troubleshooting the Furnace Control Board- czcams.com/video/phsUYxo75jU/video.html
Thermostat Wiring to a Furnace and AC Unit- czcams.com/video/GoThAlOvSts/video.html
Heat Pump Thermostat Wiring Explained- czcams.com/video/tf2OxCDwlFY/video.html
Thermostat Wiring Diagrams- czcams.com/video/h24-n9kyw0w/video.html
Clogged 90% Furnace Heat Exchanger- czcams.com/video/sNlWZEzSfrA/video.html
Why the Furnace Sequence of Operation is Important- czcams.com/video/uKsRpYmwlnM/video.html
Electrical Diagnosis Tools:
UEI DL389 Multimeter amzn.to/2xAdaJf
UEI DL479 Multimeter with temp sensor amzn.to/2jtsUbJ
Magnet Jumpers- amzn.to/2PyKPQZ
Alligator Jumpers- amzn.to/2PxqJXn
Irwin Wire Stripper/Cutter/Crimper amzn.to/2dGTj2V
Water Column Manometers
FieldpieceSDMN6 Dual Manometer Pump - amzn.to/2jyK5Ka
UEI Digital Dual Manometer - amzn.to/2CWC6BD
Supco Universal Adjustable Pressure Switch -.01wc -10.0wc - amzn.to/2G1y0py
3/16" x 3/16" x 3/16" brass barbed tee - amzn.to/2INSRhQ
1/8" NPTF x 3/16" barb fitting for reading wc pressure - amzn.to/2G563Bq
Combustion and CO Detectors:
Testo CO detector amzn.to/33yqkqK
Testo 310 Res Combustion Analyzer amzn.to/2NuYAO5
Testo 310 Res Combustion Analyzer with printer amzn.to/33vLl53
Testo 320 w printer amzn.to/33xZbUz
Vacuum Tools:
JB 6 CFM Vacuum Pump - amzn.to/2nqbvo8
CPS 4 CFM Vacuum Pump - amzn.to/2DxgPwY
Appion Valve Core Removal Tool - amzn.to/2uYr8WL
Appion Blue 3/8" to 1/4" Vacuum Hose - amzn.to/2uYlVyc
Appion Red 3/8" to 1/4" Vacuum Hose - amzn.to/2uYg6Ro
Yellow Jacket 1/4" by 1/4" 3’ hose - amzn.to/2umtcod
Appion 1/4" by 1/4" and 3/8” hose - amzn.to/2Zyxzx9
Uniweld 1/4" by 1/4" 2’ hose - amzn.to/2GFov1Y
CPS Vacuum Micron Gauge - amzn.to/2v1nM3O
JB Vacuum Pump Oil - amzn.to/2mGrlXy
Checking the Charge Tools:
Yellow Jacket Refrigerant Gauge Set amzn.to/2aenwTq
Refrigerant hoses with valves amzn.to/2aBumVI
Compact Ball Valve for Refrigerant Hose amzn.to/2KUisW8
QuickDisconnect 90 for refrigerant hose amzn.to/2MMtVcg
RectorSeal Bubble Gas Leak Detector amzn.to/2ckWACn
Fieldpiece ST4 Dual Temp Meter amzn.to/2wc1ME3
Fieldpiece Bead K Type Temp Sensor amzn.to/2DBwKfs
Fieldpiece Wet Bulb Temp Sensor amzn.to/2RRI7Tw
Fieldpiece TC24 Temp Clamp amzn.to/2qHLyjZ
Refrigerant Leak Detection Tool:
Accutrak VPE Ultrasonic Leak Detector amzn.to/2nFYKVe
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.
I'm a 26 year gas company tech and I would absolutely recommend this guy. I don't even know where he's located but he knows his stuff. Sadly, this is very rare.
He’s in southern New Jersey.
I love his videos too👍👍👍
SO true Mike. Many often think the upstairs thermostat is bad🤪😝. Last note re short-cycling? Repeat after me....FILTER FILTER FILTER ha ha. I used to practice over-the-phone triage when my techs were buried overnite. Can't TELL you how many owners didn't even know there was such a thing. Crazy but true.
@markgrove I turned a single mother's gas on a couple months ago that had always had trouble paying. I started her furnace up and it short-cycled the entire time I was there. She showed me her usage was 50 mcf/month. She lived in a 1 story flat about 1000 square. Of course she'd called the landlord time and again and no one ever checked it out. I asked about the filter and she said the landlord told her she wasn't allowed to change it but again, never sent anyone to service it. I told her to tell the owner that the GASMAN was changing it for her and she wasn't involved. No more short-cycle, no more high bills. Some people don't deserve to own property.
@@mikelilly7285 Right on. Lady prbly had/has many other issues too due to this creep. Good for you Mike!
It’s because no one wants to learn anymore. Instead of studying and watching videos like this on their free time they want to play video games and smoke weed. I’m a tech started with all HVAC stuff and now also doing hydroponics, combination boilers and everything else I love it
Thanks for the video. I was dealing with a short cycle situation that was causing my furnace to not keep up. 68deg when the thermostat is set for 72. The local repair/sales place said it was a clogged AC evaporator coil. Your video allowed to confirm that the flow restriction was causing the high limit switch to trigger. Cleaning everything, still short cycle. Then one of the comments mentioned an extra radiator for high efficiency furnaces. I pulled the blower mower, and found a radiator BEFORE the heat box, it was CAKED with hair and crud. Little elbow grease later and I have a system working like new. Thanks.
Thank you so much for this video. I see the light at the end of the tunnel.
We have been having this issue for almost 8 months. Have few different companies come and take a look at it. So far no one could diagnose the problem. Instead left me confused. So very disappointing.
I am going to have my husband look at this video and see if we can fix it our self. Or if we have some one come to fix the issue we wont be fooled this time.
These days its so hard to find some one honest and sincere to his work. My experience lately is people are more interested in doing the rush service and hand out a big bill collect money and go.
Makes me very sad and disappointed with bitter taste. And makes it hard to trust anyone.
Always carry some extra pressure switch tubing on tune-ups and service calls. The ends can often be loose or cracked from age. This will allow air infiltration causing the pressure switch to not close. Also carry a paper clip to poke debris from building up on the pressure switch tubing port at the ID motor.
Excellent lesson as always Craig!
Fantastic tips! Its always nice to check a pressure switch tube and have it disintegrates in your hand, ha ha!
@@acservicetechchannel automotive silicon paste works wonders at preserving integrity of rubber in high heat dry spots
Carrier/ Bryant….if the secondary is cracked, the pressure switch will not close, if the tubing is cracked…the secondary is failed. The secondary on those are pure garbage.
You’ll probably replace more pressure switch tubing than actual pressure switches. Very often, techs are quick to blame the pressure switch when in reality it’s the lack of vacuum causing the pressure switch not to operate properly. Must admit, I was like that also but now a little wiser.👍👍👍
Great explanation; thank you for taking the time to help out a cold homeowner!
This is exactly what I came across when I was doing the PM on the unit heaters for my customers. Greatest video on this subject, thank you.
Thanks a lot J Brian!
Dirty air filter can also cause short cycling.
Best HVAC videos on CZcams!
Sir you're good, if a person learning would know about 70 or 75 percent what you know, the furnace would stay running , here in Chicago, it gets cold, mine went out when it was cold about two years ago, i bought another furnace installed it, but i did do the things you're saying and fixed the 1 where the part went bad, i put it back in hooked it up and it worked like it did before, i took it back out, and installed the 1 i bought again, i'm happy now sir, because when it gets cold again, and that's when they really break down, if it does it again, i'll go down stairs, install the working one, test the 1 that went bag, order the part, and get it working again, i get a kick out of listening,reading, to learn things, Sir you're a bad man in a good way, you know alot.
Love the videos Craig thank you, I had a water logged inducer motor in a Lennox condensing burner a few days ago, the installers got pvc shavings down the flu vent and clogged the strainers on the collector box
Your best yet...Just got off one where the flame rod was carbon covered, It stayed fired afterward, but even after cleaning that, when the Digital T stat was satisfied it would come right back on...No heat anticipation...Replaced that, bingo...12 year old unit, never serviced...Your a great instructor bud and that's from a former instructor...Just word of mouth service for old folks or low income anymore...It's a shame the gougers are out there, but they are...Thanks for the videos you do...Keep learning guys...It makes you better...Watch this man.
Wow. This was the most comprehensive furnace video I've seen. Thanks for all the info.
You explanations are spot on. No hype, no bull. Thanks!
I appreciate that!
Thanks because my furnace randomly blew out and yes it was the limit switch was open so that means it's broken. Thanks for showing.
Great video and info. Great guest too. Thank you Bryan and Craig.
Great explanation. I wish all hvac techs were this knowledgeable!
Glad you enjoyed it!
Great video. fixed my furnace from short cycling... I always thought it was a plugged intake or exhaust it only happens in jan or feb after a snow or ice Storm. I never considered it to be the other end. When i pulled the drain hose off the blower housing water came pouring out. My drain tube makes a loop in the blower chamber and then to the floor drain and it was totally plugged with gunk. Cleaned it out and all is good now. thank you, you guys are awesome....
Also Supply air dumping on tstat, simulating false "satisfied". When unit stops, no heat or cool on tstat, initiates another call. Great vid!
Craig! ,Great explanation as always you are very detailed and explain things in a way of sequence of operation, to make things easier to grasp/ understand !
Wonderful assett to all in the hvac field.
Thank you for all your time.,and effort making these videos!
As always,i watch all your videos,
Even as a veteran of 33 years in this field,mainly as commercial refrigeration,i still learn something new daily.
Thank you sir!
Bryan Tyler Refrigeration
Helotes,Tx
I really appreciate your note Joseph!
Very thorough discussion, excellent list of associated tools and instruments. A clogged air filter will change the delta in the heat exchanger producing a high limit trip also. Louis
Absolutely correct, thanks Louis!
Craig. You will be a great teacher... ! Always a really good content..... keep up this videos...
Thanks Miguel! I am an HVACR teacher in southern NJ, glad to help!
@@acservicetechchannel Hmmm..... You don't seem to have an accent? Lol
He is a great teacher very good at what he does learned a lot from him and I appreciate it.
100% appreciation of what you do.
Thank you for your support
My experience is usually that it is a dirty flame sensor, clogged filter tripping the high limit, or a pressure switch issue (especially when it gets really cold). The first two are self explanatory, but the pressure switch has a few different reasons, but usually it is being blocked from either a PVC pipe or hard water in one of the orifices from the tubes from the pressure switch.
Natural born instructor! Explains the trade so well!
Thank you very much Dan!!! I am glad things come across well to you!
Great video Craig. Also, check the blower run capacitor. A weak capacitor can slow the blower which can cause furnace to go out on High Limit.
Obstruction of the combustion air intake or exhaust will upset the system indeed, including ice or a nest; or like one customer found out at midnight last night steel wool shoved way up the pvc for winterization against pests was bad idea too. Diagnosed with monometer T / meter technique learned on this channel.
I appreciate your videos,you make it easy to understand.I went to an HVAC school but I forgot to pay attention lol
Thank you! Grateful for your support
Great info! Thank you! Helping me big time to troubleshoot my first condensing high efficiency furnace.
You Sir are a natural teacher! Subscribed
Wow, thanks!
Craig Happy new year to you and your family. Thanks for sharing your knowledge to everyone. God bless you.
Happy new year!
In my work with furnaces in manufactured homes, quite often a simple bi-metallic coil thermostat is used. These have a 'heat anticipator' which is specifically designed to govern length of heat cycle. Just last week I had a complaint of 4 years of short cycling. The anticipator was set for shortest cycle possible. 5 min fix. : )
Great tip Robnord1!
Great comment, I was about to point this out when I came across your comment. This was more of a common short-cycle problem with the T-87 Honeywell-type stats, for example. For a precise setting of the anticipator, I always removed the front cover of the stat and remove the white wire from the W connection then wrap a piece of single-strand stat wire 10 times around my clamp-on amp probe, then used the wire to jump from R to W on the stat to send the signal to the furnace. This would magnify the reading by 10 then remove the jumper and reattach the W wire. Then divide the number by 10 and set the anticipator with the exact setting. With the advent of newer electronic type stats, the anticipator problem has been solved by an
integral amp reading and automatic adjustment. The anticipator was frequently overlooked by the installers but was often a nuisance call.
We had six years of short cycling…air filter had no dirt around edges.
Hvac new graduate found the installer did not follow air flow opening specifications, 1940’s
farmhouse.
3 previous hvac maintainers did not catch this flaw.
Excellent instructional video. Thank you.
Glad it was helpful!
I had the soldier problem on the back of the board on my Gibson . i think it’s called a cold soldier joint. it was not heated hot enough on the pin when manufactured. It was a easy fix .
Thanks for such a detailed video.
I see this so often in the field
Thanks UR a great teacher. I always adjust my equipment to run long cycles to make all the controls last longer. Unfortunately some of the new equipment it’s hard to adjust it to do this.
I have a Bryant Hi tech thermostat and I can’t figure out how I can like send the heating cycle.
Thank you again Craig
Thank your videos I really like them.
Thank you very much Juan!
Really good information thank you very very much . I appreciate it
Great video as always
Thanks a lot Kenneth!
Awesome work
great teacher
Thanks a lot Dennis!
Excellent video!
Thanks a lot Chuck!
Really great video
Wow super knowledgeable! Thanks for the info! Cheers!
Glad it was helpful!
Great technical info
Thanks a lot Gonz!
I had this problem with the 80+ downflow gas furnace in my garage. I found that the thermostat was being influenced by the hot air from the furnace. I could have moved the t-stat, but I built a semi-shroud around it, so the airflow was minimal around the t-stat. Simple problem solved.
Thank you very much for making this very educational video,
I would like to add that a dirty A coil could be the reason for number 6.
Craig thank you, yet another awesome video. Happy holidays my friend.
I know this isn’t a Q&A type of forum, but my question ties into this video.
I have a problem with my gas furnace cycling, but only when it’s overly windy outside. I was wondering if anyone else has experience this issue. I really do nothing in the way troubleshooting. Just play with the system a bit and it fire back up eventually.
Sorry for long post. This is just annoying me as the temp is dropping here in NJ.
I had this problem when it was very windy outside (50-60 MPH gusts), it was sometimes causing a down-draft that would shut off the furnace flame, then a second later the flame would come back on.
My furnace would start up and the flame would come on, but most of the time it would shut down before the blower came on. I thought it was a bad primary limit. But I noticed the high voltage line going to the igniter was touching several other wires (including the flame sensor wire), so I re-routed the high voltage line to isolate it, and haven't had a problem since.
Thank you for your videos
My pleasure!
Outstanding. 👏
Nice job buddy!
great video, thank you
This guy is 👍 👌 👍 👌 👍 👌 👍 👌
Good info, Thanks for sharing
Thanks a lot Dean Martin!
@@acservicetechchannel If you're teaching at a tech school, I hope they're paying you what your worth. You know your stuff. You'r an asset to the Hvac community.
That was really good. If a new replacement, it could be too large.
Good video!
thanks a lot xbreaselx814!
Thanks!☺
Thanks David!
Guauuuuu good job im from Chicago I vn watching some of your videos thank you so much
Great video.Great book also.😜
Thanks a lot Phillip!
Thank you
Thank you, Great video!) MC Tapch.
Got ya, name change, thanks a lot! I appreciate you!
The most common cause of short cycling I see is a thermostat being bombarded by hot air from a poorly located heat duct. The thermostat being mounted too high on the wall can also cause short cycling.
Another great tip, thanks!
Awesome thank you
Thank you for your support
Awesome job thank you so much
You are very welcome
Thanks!!!! service tech...
Glad to help eman3208, thanks!
As an industrial engineer, I'm of the opinion today's gas furnace is over-engineered and constructed with faulty/inferior designs and materials. Simple solution: heat with wood. More BTU's for less money, along with basically no maintenance other than the annual chimney sweep. Of course, not all applications will allow for wood heat.
I really like it.
Thanks!!!!!
Thanks a lot Xtreme Comfort!
Hi Craig, this is a wonderful learning video. Learned a lot. Appreciate it!
I just had my furnace do the cyclic shut off and immediate restart and immediate shut off...
I remembered my wife brought home one of the high/dense furnace filter, which I reluctantly put in lately.
I guessed that may be the cause and immediately replaced it with a very light/porous furnace filter, and the furnace just ran for 25 minutes without cycling...
Hopefully that's it!
Update: This id day after: Furnace cycles still, but not as frequent as before… I also have a tripping flame rollout switch, which only trips once in few days/weeks, so it may be or may be not related…
I would check the thermal limit switch now….
you should not be manually resetting your flame rollout switch without actually understanding why it is tripping.
Our furnace short cycles it runs a total of four times before it stops for a while I have the Merv 13 filter in my furnace and in the air return in the house so I'm thinking that maybe our issue.. I'm not sure.. so I'm going to buy a less dense filter for the furnace and cold air return in the house and see if that helps!
Hello Craig, first off I really appreciate the awesome video. Secondly, I am going to be installing my first heat pump air handler in a few days as a part of an interview. I have been looking all over the internet for a video of how to wire the high voltage (not low voltage thermostat wiring If you accidentally misread it) from start to finish. I would greatly appreciate if you could. You are the only tech I feel would make a great video on how to do so. Also are there any other tips you would give someone installing a heat pump for the first time.
Just FYI I have been doing hvac for a little while now. I have wired condensing units, indoor furnaces just never a heat pump air handler.
I don't have a video on exactly that but you need to have a disconnect switch within a servicable distance from the air handler. Often we put it on or right next to the air handler. Make sure the wire is cased if it is indoors such as in MC, seal tight, metal conduit. Check to see what kw heat package is installed and if it has breakers or fuses attached as the incoming power wire to the air handler. If it does then you know what amperage the wire must be and what breaker size in the breaker box the wire should be protected by. If it is 240v whip at 30amp then 10 gauge wire, 40amp then 8 gauge wire, 60amp 6 or 4 gauge wire, 90amp 2 gauge wire. Of course whips can be a slighlty smaller size since they are a short distance but I usually still size them the same as I would a long wire run so it is not a weak link. Anyway, if it does not have strip heating then it may just need a 15amp breaker which the air handler can be wire with 14 gauge. However if the breaker size in the building is 20 amp then 12 gauge wire would be used. You need to look at the rating plate of the air handler though to verify what it says as the max amp rating to be sure of the size if there is no strip heating. If aluminum wire is used then anti oxidant compound must be applied to the stranded alum connection before tightening the lug. Make sure you are not doing more than just working in the disconnect, whip, and tying unit in unless you are a licensed electrician. I hope this helps you!
Thank you. I hope I can be as good of a tech as you some day
Please talk about duckwork is sizing too small it makes systems short cycle by Opening the high limit switch for the heat exchange
Thanks! Greg for your videos you're awesome dude
thank you for sharing their partner Excellent video!!!!.
Thanks Jimbola77!
I had a short cycling 90 percent furnace that had dog hair restricting air flow on the high efficiency part of the heat exchanger. Some systems can have design flaws that restrict air flow too.
Thanks for sharing. Do you have a video on why A/C unit cycles on and off really fast at the condenser?
Had a couple of them disks switches that were weak. They still worked but would trip at different temps at random times.
Yeah absolutely, thats what happens! They rarely break completely unless it is at the contacts where they are burnt, thanks!
Hi Craig! I wondering why you didnt mention a clogged primary or secondary heat exchanger for this issue. Is that not a possibility for this type of problem? Thanks!
I relocated my combustion area intake pipe,that was taking in (saturated with water) air( while it rains all the time here for a few weeks. The pipe was probably sucking in lots of raindrops into the combustion area.and as soon as I relocated that intake to combustion area pipe to a dryer area,it then stopped the short cycling
Just fixed my furnace because you're video. I checked the presure switch and the tube was cracked causing the unit to shut off.
I had a tricky call with an Armstrong furnace and short cycling . The fault code indicated the pressure switch was closed when the inducer was OFF. Typically the contacts have stuck together and a new pressure switch is in order. On this call the furnace wasn't that old, so I confirmed everything seemed normal. Plenty of static pressure to close the switches etc. A few days later I was back. Same fault code. This time, instead of using a jumper wire to make a call for heat I let the thermostat do its job. The tstat was short cycling the inducer . It has lost it's marbles and wasn't giving the fan wheel enough time to stop spinning before making another call for heat. Thus creating the fault of pressure switch closed with inducer motor off. I suppose if I were a way smart Allied Air engineer I would add some appropriate time delay logic to the board to avoid the issue. After installing new tsat , problem solved.
Excellent video! I have a question. I have a short cycling issue with my tempstar furnace. I checked the collector box and found that the corners and edges inside the collector box were melted. What type of short cycling can cause that melting.
Nice video
So nice
Hi Craig! Do you have any video about combustion analysis?. I notice almost 90% of furnaces installed dont have a combustion analycis done...I understand contractors dont do it thinking that the furnace is already calibrated...For what I read from manufacturers, you need to calibrate. Wich means C.A. has to be done...
Ask the customer if anybody has done any electrical work on the furnace or if the power had been disconnected and reconnected. If you have the polarity backwards, the furnace will come on for about five or 10 seconds, and then shut the gas off. I know this happens with Rheem furnace not sure about some of the other brands.
Thanks
Thanks Sang!
I was getting an attempt for the gas furnace to start and then quit going into lockout. I cleaned the flame sensor and reinstalled it with no difference. Meter is series with the flame sensor provided zero dc reading. Replaced the electronic board and the furnace is working great. The board is one of the top 5 things to go. It was on a Carrier Gas Furnace. So if you are getting no DC voltage back when the meter is in series with the flame sensor and the flame sensor has 110 volts, it is probably a bad board as it was in my case.
What is the likely problem if my furnace short cycles and does not come up to temperature with a new clean filter in it, but when the filter is removed the furnace works OK? It worked in previous years with a filter. Thanks for any ideas.
gas flow can cause gas pressure sensor problems.
If there is restriction via faulty regulator or dirt in line then gas pressure can read fine until furnace starts and flow restriction can't keep up with demand. This results in low pressure at safety switch shutting it down/ short cycling.
I just came across a short cycle furnace. It didn't give me a code but would fire up, run awhile then shut off. The grill cover was blocking the exhaust/intake
Goodman furnace stop working was running fine other day. The Mother board was changed last winter the blower was leaking water but was resealed water pump works fine. I turned thermostat control off main switch off to furnace Wait 5mn turn switch back on then control to 65° heat kicked on but fan not run then unit shut down.
Need your opinion on a NEST Thermostat 3rd Generation. Have it installed with out a C wire, do you think it will be a problem with my gas furnace in the future?
I have a heat pump, and the interior blower motor began blowing air very slowly. It's not on slow speed, the blower is barely turning. I checked the relay and it's okay. I Haven't took the blower motor apart yet. I wonder if a hard start or auxiliary capacitor might be needed. I have a rheem RQRM-A036JK010 model.
Hi can you tell me what the dip switches should be at on a new carrier 59TP6 100k BTU furnace I have a ecobee and my installer just left it at the factory positions and told me to leave fan on all the time.Thank you
Should the flame rectification be erratic like jumping around between .01 to anywhere up to 2.5 but spends most of the time somewhere around 1.0 to 1.5 but jumping around? The flame sensor looks like new but I did go ahead and cleaned it and checked for cracks in the porcelain and didn't see any. Any help would really be appreciated .
Thank You
Bob
I'm learning a lots every time I'm watching your video. I'm going to take my D2 license. Can you text me good lessons that i can prepare myself for the text therefore i could get it for the time taking it. Thanks in advance and may God continue bless you and your family.. know that Jesus loves you
i have a rheem x13 80% 100k btu, is it normal for it to run then after 15min it shuts the flame off then about 5min it turns the flame back on but the speed of the blower fan varies between flame on and off?
My issue, a year or so ago, was my thermal limit switch was tripping too soon. Had the HVAC company replace it, and all was fine. They needed to lower the gas pressure a bit also.
Yeah sometimes they just wear out over time, thanks!
Hope they did a combustion analysis
I had a (carrier) 80+ would go thru sequence but cut out as soon as it would ignite roughly 1.5 sec. Check all safeties , flame rod , press switches eventually found out it was the board as soon as flame engaged it shut down the unit. Replaced pc board
i have gotten intermittent issues with 90% goodman furnaces (new ones too)error code 1, exceeding combustion tries/lock out and everytime i got there , the unit would be working fine. i had one today and after checking everything , the only thing i found that kinda suspect is that the dual pressure switch, rated for 1.2 wc and air proving switch rated 0.10 seemed to be getting similar pressures 1.6 to 1.8 give or take. Is this normal or what could be the cause of this ?..i blew out the drain line too btw....thanks in advance!
Do have a video explaining optimal cycles per hour for different equipment, i.e high efficiency furnace?
People that won’t do needed maintenance can have this problem too clogged filters clogged fan and coils cause low air flow and higher temps
Absolutely correct! Thanks Walt!
We have a service call where a unit trip out the high limit switch. Alot of troubleshooting and the only thing we found was the hot air was being pulled into the return (return and supplies in ceiling and this is an old church we didn't do this ductwork and had to reconfigure, didnt like it from the start.) Thermostat was right by the return about 2 foot below. The hot air was not reaching the thermostat to satisfy, cause the furnace high limit to trip. The whole setup was screwed, we moved the return down below thermostat and relocated the thermostat. Problem solved. We didnt have many options for relocating anything else, they just had a company install this system. Crappie install caused this one
If the filter and fan are dirty, there is also a good chance that the secondary heat exchanger fins are partially plugged also depending on the style of secondary used.