Durham Region Air Conditioning Repair, Service and Installation
If you are an owner of Ruud furnace or operate it at your work, you may encounter with Ruud furnace error codes appearing in the operation process. The tables on the page describe the codes, flashes, blinks and other problem signals and let you understand what is going on with the equipment at a certain moment.
Ruud R801T Furnace Error Code
CODE: 0.
RESULT: Standby.
RESULT: Standby.
CODE: C.
RESULT: Compressor on (cooling or heat-pump heat).
RESULT: Compressor on (cooling or heat-pump heat).
CODE: H.
RESULT: Gas heat on.
RESULT: Gas heat on.
CODE: F.
RESULT: Continuous fan on.
RESULT: Continuous fan on.
CODE: 10.
RESULT: 1 hour lockout.
RESULT: 1 hour lockout.
CODE: 11.
RESULT: Failed ignition.
RESULT: Failed ignition.
CODE: 12.
RESULT: Low flame sense.
RESULT: Low flame sense.
CODE: 13.
RESULT: Flame lost.
RESULT: Flame lost.
CODE: 14.
RESULT: Unexpected flame.
RESULT: Unexpected flame.
CODE: 20.
RESULT: Twinning fault.
RESULT: Twinning fault.
CODE: 22.
RESULT: Main limit open.
RESULT: Main limit open.
CODE: 26.
RESULT: Line and neutral reversed.
RESULT: Line and neutral reversed.
CODE: 33.
RESULT: Mrlc (manual reset limit control) (aka roll-out) open.
RESULT: Mrlc (manual reset limit control) (aka roll-out) open.
CODE: 55.
RESULT: Pressure switch stuck closed when should be open.
RESULT: Pressure switch stuck closed when should be open.
CODE: 57.
RESULT: Press switch stuck open when should be closed.
RESULT: Press switch stuck open when should be closed.
CODE: 61.
RESULT: Blower fault-blower unable to run.
RESULT: Blower fault-blower unable to run.
CODE: 93.
RESULT: Internal control fault.
RESULT: Internal control fault.
Ruud U98V Furnace Error Code
FLAME LED: OFF.
RESULT: No flame is detected.
RESULT: No flame is detected.
FLAME LED: Rapid blink.
RESULT: Unexpected flame.
RESULT: Unexpected flame.
FLAME LED: Slow blink.
RESULT: Marginal flame sense.
RESULT: Marginal flame sense.
FLAME LED: Steady ON.
RESULT: Normal flame detected.
RESULT: Normal flame detected.
STATUS LED: Steady ON.
RESULT: Furnace.
RESULT: Furnace.
STATUS LED: 1 Blink.
RESULT: Ignition failure, 1 HR lockout.
FIX: Reboot system.
RESULT: Ignition failure, 1 HR lockout.
FIX: Reboot system.
STATUS LED: 2 Blinks.
RESULT: Pressure switch stuck open, switch will not close when inducer is on.
FIX: Try to manually close the switch, replace the switch, or check blowers and vents for air pressure.
RESULT: Pressure switch stuck open, switch will not close when inducer is on.
FIX: Try to manually close the switch, replace the switch, or check blowers and vents for air pressure.
STATUS LED: 3 Blinks.
RESULT: Limit switch open, main limit or roll out control
FIX: Check for a restricted air vent, loose blower wheel, a defective blower, or a dirty air filter.
RESULT: Limit switch open, main limit or roll out control
FIX: Check for a restricted air vent, loose blower wheel, a defective blower, or a dirty air filter.
STATUS LED: 4 Blinks.
RESULT: Pressure switch stuck closed, switch will not open.
FIX: Check for an obstruction in the pressure tubing.
RESULT: Pressure switch stuck closed, switch will not open.
FIX: Check for an obstruction in the pressure tubing.
STATUS LED: 5 Blinks.
RESULT: Not applicable.
RESULT: Not applicable.
STATUS LED: 6 Blinks.
RESULT: Line and neutral reversed.
FIX: Control board or the furnace's ground could be defective.
RESULT: Line and neutral reversed.
FIX: Control board or the furnace's ground could be defective.
POWER LED: OFF.
RESULT: No power (24 VAC) to control board.
RESULT: No power (24 VAC) to control board.
POWER LED: ON.
RESULT: Control is powered.
RESULT: Control is powered.
Ruud R802P Furnace Error Code
FLAME LED: OFF.
RESULT: No flame is detected.
RESULT: No flame is detected.
FLAME LED: Rapid Blink.
RESULT: Unexpected Flame.
RESULT: Unexpected Flame.
FLAME LED: Slow Blink.
RESULT: Marginal Flame Sense.
RESULT: Marginal Flame Sense.
FLAME LED: Steady ON.
RESULT: Normal Flame Detected.
RESULT: Normal Flame Detected.
STATUS LED: Steady ON.
RESULT: Normal Fault detected.
RESULT: Normal Fault detected.
STATUS LED: 1 Blink.
RESULT: Ignition failure, 1 HR lockout.
RESULT: Ignition failure, 1 HR lockout.
STATUS LED: 2 Blinks.
RESULT: Pressure switch stuck open switch will not close when inducer is on.
RESULT: Pressure switch stuck open switch will not close when inducer is on.
STATUS LED: 3 Blinks.
RESULT: Limit switch open main limit or roll-out control.
RESULT: Limit switch open main limit or roll-out control.
STATUS LED: 4 Blinks.
RESULT: Pressure switch stuck closed. Switch will not open.
RESULT: Pressure switch stuck closed. Switch will not open.
STATUS LED: 5 Blinks.
RESULT: Not applicable.
RESULT: Not applicable.
STATUS LED: 6 Blinks.
RESULT: Line and Neutral reversed.
RESULT: Line and Neutral reversed.
POWER LED: OFF.
RESULT: No power (24VAC) to control board.
RESULT: No power (24VAC) to control board.
POWER LED: ON.
RESULT: Control is powered.
RESULT: Control is powered.
Ruud R96P Furnace Error Code
GREEN LED: ON.
RESULT: Normal operation.
RESULT: Normal operation.
GREEN LED: 1 Flash.
RESULT: Ignition failure (4 trials).
RESULT: Ignition failure (4 trials).
GREEN LED: 2 Flashes.
RESULT: Pressure switch stuck open.
RESULT: Pressure switch stuck open.
GREEN LED: 3 Flashes.
RESULT: Limit switches open.
RESULT: Limit switches open.
GREEN LED: 4 Flashes.
RESULT: Pressure switch stuck closed.
RESULT: Pressure switch stuck closed.
GREEN LED: 5 Flashes.
RESULT: Twin fault.
RESULT: Twin fault.
GREEN LED: 6 Flashes.
RESULT: Brownout voltage.
RESULT: Brownout voltage.
GREEN LED: 7 Flashes.
RESULT: Hot and neutral reversed or no ground.
RESULT: Hot and neutral reversed or no ground.
GREEN LED: Continuous.
RESULT: Gas valve relay short.
RESULT: Gas valve relay short.
YELLOW LED: Rapid Blink.
RESULT: Flame out of sequence.
RESULT: Flame out of sequence.
YELLOW LED: Slow Blink.
RESULT: Low flame or no flame.
RESULT: Low flame or no flame.
YELLOW LED: ON.
RESULT: Flame present.
RESULT: Flame present.
See What Our Customers Are Saying:
Aug 8, 2025
We are very happy to recommend this company to everyone. Our furnace broke down on Sunday morning. We phoned them and before noon Grant the owner showed up. He worked on the furnace for about a hour not wanting to give up to fix the problem. The furnace was 17 years old. I was the one talking about replacing it. End result was the next day it was all done. On the Sunday Bob came over with heaters to warm up the house. We decided to replace the water heater at the same time. Thanks Grant for the excellent work. Thumbs up.
Aug 8, 2025
Right on time. Explained how to work the HRV in a different way so the house would not be so dry. Changed my whole house water filter for me as well. Friendly, helpful, caring service!
Feb 18, 2025
Very pleased with the professional service that TwinTech Heating and Cooling provided in replacing my furnace. I got several quotes from different service providers. Their price was excellent and they explained the features very well. We are very glad we went with TwinTech and highly recommend their services.
Feb 18, 2025
We were new homeowners in need of a second opinion. TwinTech Heating & Cooling were Amazing and professional. Very knowledgeable and great service all around. Recommend to anyone looking for honest and reliable services. Treated with respect and care. Thank you Greg, Mitch and Bob!
Feb 18, 2025
TwinTech is an excellent and honest company! I called them for a second opinion after being told by another company that I needed to replace my furnace. Turns out this was not the case at all! I did not need a new furnace. TwinTech did not push to make an unnecessary sale and saved me from a huge expense. Bob and Mitch were extremely professional and above all honest! I definitely recommend TwinTech!
Feb 18, 2025
Amazing experience with TwinTech Heating & Cooling! Their team was professional, knowledgeable, and efficient from start to finish. They installed my new furnace quickly and left everything spotless. The technicians took the time to explain everything and made sure I was comfortable with the system before they left. Great customer service and fair pricing. I highly recommend them for anyone needing HVAC services!
Feb 18, 2025
Great experience all around. Bob was sharp and easy to talk to, and Greg handled the installation perfectly. Would hire them again in a heartbeat.
Aug 17, 2024
I returned from vacation to find my AC unit on the Fritz. After calling way too many places I connected with TwinTech. Ive used the company in the past for my furnace so I was happy when I recognized Greg at my front door. Hes great and the service is always top notch. Id highly recommend using twintech for honest, superior service in the Durham region. Thanks!
Aug 13, 2024
I called Twin Tech when my air conditioning stopped working. Greg came over to diagnose the issue - the same day. He was able to diagnose the issue and resolve it quite quickly. Although it was a quick fix, Greg was very thorough in explaining the issue and provided great advice. Not to mention, I felt very comfortable having Greg in my home - which I consider very important when hiring a service provider. Twin Tech will be my go-to from now on. Thank you!!
Aug 12, 2024
Just hired TwinTech Heating & Cooling to do an A/C Unit removal & reinstall to allow for landscaping access on the side of my house, and they were wonderful!
Bob, Greg & Mitch make a great team! Quick appointment times, super knowledgeable, expert troubleshooting capabilities & very customer service oriented.
I would highly recommend them for all of your HVAC needs! Great job guys!!
See What Our Customers Are Saying:
Aug 8, 2025
We are very happy to recommend this company to everyone. Our furnace broke down on Sunday morning. We phoned them and before noon Grant the owner showed up. He worked on the furnace for about a hour not wanting to give up to fix the problem. The furnace was 17 years old. I was the one talking about replacing it. End result was the next day it was all done. On the Sunday Bob came over with heaters to warm up the house. We decided to replace the water heater at the same time. Thanks Grant for the excellent work. Thumbs up.
Aug 8, 2025
Right on time. Explained how to work the HRV in a different way so the house would not be so dry. Changed my whole house water filter for me as well. Friendly, helpful, caring service!
Feb 18, 2025
Very pleased with the professional service that TwinTech Heating and Cooling provided in replacing my furnace. I got several quotes from different service providers. Their price was excellent and they explained the features very well. We are very glad we went with TwinTech and highly recommend their services.
Feb 18, 2025
We were new homeowners in need of a second opinion. TwinTech Heating & Cooling were Amazing and professional. Very knowledgeable and great service all around. Recommend to anyone looking for honest and reliable services. Treated with respect and care. Thank you Greg, Mitch and Bob!
Feb 18, 2025
TwinTech is an excellent and honest company! I called them for a second opinion after being told by another company that I needed to replace my furnace. Turns out this was not the case at all! I did not need a new furnace. TwinTech did not push to make an unnecessary sale and saved me from a huge expense. Bob and Mitch were extremely professional and above all honest! I definitely recommend TwinTech!
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