Durham Region Air Conditioning Repair, Service and Installation
Armstrong Air is the professional's choice in home heating & cooling. Including oil & gas furnaces, air conditioners, heat pumps, package units & air handlers.
CODE: E105.
RESULT: Device communication problem - No other devices on RS BUS (Communicating systems only).
FIX: Equipment is unable to communicate indicates numerous message errors. In most cases errors are related to electrical noise. Make sure high voltage power is separated from RSBus. Check for mis-wired and/or loose connections between the stat, indoor unit and outdoor unit. Check for a high voltage source of noise close to the system. Fault clears after communication is restored.
RESULT: Device communication problem - No other devices on RS BUS (Communicating systems only).
FIX: Equipment is unable to communicate indicates numerous message errors. In most cases errors are related to electrical noise. Make sure high voltage power is separated from RSBus. Check for mis-wired and/or loose connections between the stat, indoor unit and outdoor unit. Check for a high voltage source of noise close to the system. Fault clears after communication is restored.
CODE: E110.
RESULT: Low line voltage.
FIX: Line Voltage low (Voltage tower than nameplate rating). Check power line voltage and correct. Alarm clears 5 seconds after fault recovered.
RESULT: Low line voltage.
FIX: Line Voltage low (Voltage tower than nameplate rating). Check power line voltage and correct. Alarm clears 5 seconds after fault recovered.
CODE: E111.
RESULT: Line voltage polarity reversed.
FIX: Reverse line power voltage wiring. System resumes normal operation 5seconds after fault recovered.
RESULT: Line voltage polarity reversed.
FIX: Reverse line power voltage wiring. System resumes normal operation 5seconds after fault recovered.
CODE: E112.
RESULT: Ground not detected.
FIX: System shuts down. Provide proper earth ground. System resumes normal operation 5 seconds after fault recovered.
RESULT: Ground not detected.
FIX: System shuts down. Provide proper earth ground. System resumes normal operation 5 seconds after fault recovered.
CODE: E113.
RESULT: High line voltage.
FIX: Line Voltage high (Voltage higher than nameplate rating). Provide power voltage within proper range. System resumes normal operation 5seconds after fault recovered.
RESULT: High line voltage.
FIX: Line Voltage high (Voltage higher than nameplate rating). Provide power voltage within proper range. System resumes normal operation 5seconds after fault recovered.
CODE: E114.
RESULT: Line voltage frequency out of range.
FIX: No 60 Hertz power. Check voltage and line power frequency. Correct voltage and frequency problems. System resumes normal operation 5seconds after fault recovered.
RESULT: Line voltage frequency out of range.
FIX: No 60 Hertz power. Check voltage and line power frequency. Correct voltage and frequency problems. System resumes normal operation 5seconds after fault recovered.
CODE: E115.
RESULT: Low 24V.
FIX: 24 Volt Power high (Range is 18 to 30 Volts). Check and correct voltage. Check for additional power robbing equipment connected to system. May require installation of larger VA transformer to be installed in furnace/air handler. Clears after fault recovered.
RESULT: Low 24V.
FIX: 24 Volt Power high (Range is 18 to 30 Volts). Check and correct voltage. Check for additional power robbing equipment connected to system. May require installation of larger VA transformer to be installed in furnace/air handler. Clears after fault recovered.
CODE: E116.
RESULT: High 24V.
FIX: 24 Volt Power high (Range is 18 to 30 Volts) Check and correct voltage. Check for proper line voltage (120V 240V etc) to equipment. Clears when control senses proper voltage.
RESULT: High 24V.
FIX: 24 Volt Power high (Range is 18 to 30 Volts) Check and correct voltage. Check for proper line voltage (120V 240V etc) to equipment. Clears when control senses proper voltage.
CODE: E117.
RESULT: Poor ground detected (Warning only).
FIX: Provide proper grounding for unit. Check for proper earth ground to the system. Warming only will clear 30 seconds after fault recovered.
RESULT: Poor ground detected (Warning only).
FIX: Provide proper grounding for unit. Check for proper earth ground to the system. Warming only will clear 30 seconds after fault recovered.
CODE: E120.
RESULT: Unresponsive device (Communicating systems only).
FIX: Usually caused by delay in outdoor unit responding to indoor unit poling. Recycle power. Check all wiring connections. Cleared after unresponsive device responds to any inquiry.
RESULT: Unresponsive device (Communicating systems only).
FIX: Usually caused by delay in outdoor unit responding to indoor unit poling. Recycle power. Check all wiring connections. Cleared after unresponsive device responds to any inquiry.
CODE: E124.
RESULT: Active communicating thermostat signal missing for more than 3 minutes (Communicating systems only).
FIX: Equipment lost communication with the thermostat. Check four wiring connections, ohm wires, and cycle power at the thermostat. Alert stops all services and waits for heart beat message from thermostat (subnet controller). Cleared after valid thermostat (subnet) message is received.
RESULT: Active communicating thermostat signal missing for more than 3 minutes (Communicating systems only).
FIX: Equipment lost communication with the thermostat. Check four wiring connections, ohm wires, and cycle power at the thermostat. Alert stops all services and waits for heart beat message from thermostat (subnet controller). Cleared after valid thermostat (subnet) message is received.
CODE: E125.
RESULT: Control failed self check, internal error, failed hardware. Will restart if error recovers, Integrated control not communicating Covers hardware errors (flame sense circuit faults, pin shorts, etc).
FIX: Hardware problem on the control. Cycle power on control. Replace if problem prevents service and is persistent. Cleared 300 seconds after fault recovered.
RESULT: Control failed self check, internal error, failed hardware. Will restart if error recovers, Integrated control not communicating Covers hardware errors (flame sense circuit faults, pin shorts, etc).
FIX: Hardware problem on the control. Cycle power on control. Replace if problem prevents service and is persistent. Cleared 300 seconds after fault recovered.
CODE: E126.
RESULT: Control internal communication problem.
FIX: Hardware problem on the control. Cycle power on control. Replace if problem prevents service and is persistent. Cleared 300 seconds after fault recovered.
RESULT: Control internal communication problem.
FIX: Hardware problem on the control. Cycle power on control. Replace if problem prevents service and is persistent. Cleared 300 seconds after fault recovered.
CODE: E131.
RESULT: Corrupted control parameters (Verify configuration of system) (Communicating systems only).
FIX: Reconfigure the system. Replace control if heating or cooling is not available. Only applicable in the communicating mode not in startup. Exit from Commissioning and Execute Se+ factory Default mode. Control will still operate on default parameter settings.
RESULT: Corrupted control parameters (Verify configuration of system) (Communicating systems only).
FIX: Reconfigure the system. Replace control if heating or cooling is not available. Only applicable in the communicating mode not in startup. Exit from Commissioning and Execute Se+ factory Default mode. Control will still operate on default parameter settings.
CODE: E180.
RESULT: Outdoor air temperature sensor failure. Only shown if shorted or out of range (Communicating systems only).
FIX: Compare outdoor sensor resistance to temperature resistance chartsin unit installation instructions. Replace sensor pack if necessary. At beginning of (any) configuration, furnace or air handler control will sense outdoor air and discharge air temperature sensor(s) If detected (reading in range), appropriate feature will be set as installed and that could be seen in 'About' screen. In normal operation after control recognizes sensors, alarm will be sent if valid temperature reading is lost. To get rid of setting and alarm, redo configuration and make sure that temperature sensor is marked as not installed in indoor Unit 'About' screen. When indoor unit control is replaced thermostat will 'tell' new control if temperature sensor is in system or not. Clears 30 seconds after fault recovered.
RESULT: Outdoor air temperature sensor failure. Only shown if shorted or out of range (Communicating systems only).
FIX: Compare outdoor sensor resistance to temperature resistance chartsin unit installation instructions. Replace sensor pack if necessary. At beginning of (any) configuration, furnace or air handler control will sense outdoor air and discharge air temperature sensor(s) If detected (reading in range), appropriate feature will be set as installed and that could be seen in 'About' screen. In normal operation after control recognizes sensors, alarm will be sent if valid temperature reading is lost. To get rid of setting and alarm, redo configuration and make sure that temperature sensor is marked as not installed in indoor Unit 'About' screen. When indoor unit control is replaced thermostat will 'tell' new control if temperature sensor is in system or not. Clears 30 seconds after fault recovered.
CODE: E200.
RESULT: Hard Lock out - Rollout circuit open or previously open.
FIX: Correct cause of rollout trip or replace flame rollout switch. Test furnace operation. Cleared after fault recovered.
RESULT: Hard Lock out - Rollout circuit open or previously open.
FIX: Correct cause of rollout trip or replace flame rollout switch. Test furnace operation. Cleared after fault recovered.
CODE: E201.
RESULT: Indoor blower/communication failure. Unable to communicate with blower motor.
FIX: Indoor blower communication failure including power outage. Lost communication with indoor blower motor. Possible causes: motor not powered, loose wiring. Problem may be on control or motor side. Cleared after fault recovered.
RESULT: Indoor blower/communication failure. Unable to communicate with blower motor.
FIX: Indoor blower communication failure including power outage. Lost communication with indoor blower motor. Possible causes: motor not powered, loose wiring. Problem may be on control or motor side. Cleared after fault recovered.
CODE: E202.
RESULT: Indoor blower motor mismatch - indoor motor horsepower does not match unit capacity.
FIX: Incorrect appliance capacity code selected. Check for proper configuring under Unit Size Code for Furnace/Air Hander on configuration guide or in installation instructions. Cleared after the correct match is detected following a reset. (Remove thermostat from system while applying power and reprogramming).
RESULT: Indoor blower motor mismatch - indoor motor horsepower does not match unit capacity.
FIX: Incorrect appliance capacity code selected. Check for proper configuring under Unit Size Code for Furnace/Air Hander on configuration guide or in installation instructions. Cleared after the correct match is detected following a reset. (Remove thermostat from system while applying power and reprogramming).
CODE: E203.
RESULT: Appliance capacity size is NOT programmed. Invalid unit codes. Refer to configuration flow chart.
FIX: No appliance capacity code selected. Check for proper configuring under Unit Size Codes for Furnace on configuration guide or in installation instruction. Critical Alert Cleared after valid unit code is read following a reset (remove thermostat from system while applying power and reprogramming).
RESULT: Appliance capacity size is NOT programmed. Invalid unit codes. Refer to configuration flow chart.
FIX: No appliance capacity code selected. Check for proper configuring under Unit Size Codes for Furnace on configuration guide or in installation instruction. Critical Alert Cleared after valid unit code is read following a reset (remove thermostat from system while applying power and reprogramming).
CODE: E204.
RESULT: Gas valve mis-wired.
FIX: Check gas valve operation and wiring. Clears when repaired control.
RESULT: Gas valve mis-wired.
FIX: Check gas valve operation and wiring. Clears when repaired control.
CODE: E205.
RESULT: Gas valve control relay contact shorted.
FIX: Check wiring on control and gas valve. If wiring is correct replace control.
RESULT: Gas valve control relay contact shorted.
FIX: Check wiring on control and gas valve. If wiring is correct replace control.
CODE: E206.
RESULT: Gas valve second stage relay failure.
FIX: Furnace will operate on 1st stage for remainder of the heating demand. Will clear after fault recovered. If unable to operate 2nd stage replace control.
RESULT: Gas valve second stage relay failure.
FIX: Furnace will operate on 1st stage for remainder of the heating demand. Will clear after fault recovered. If unable to operate 2nd stage replace control.
CODE: E207.
RESULT: Hot surface igniter sensed open - Refer to troubleshooting.
FIX: Measure resistance of hot surface igniter. Replace if open or not within specified range found in 10M. Resumes normal operation after fault is cleared.
RESULT: Hot surface igniter sensed open - Refer to troubleshooting.
FIX: Measure resistance of hot surface igniter. Replace if open or not within specified range found in 10M. Resumes normal operation after fault is cleared.
CODE: E223.
RESULT: Low pressure switch failed open.
FIX: Check pressure (inches W.C) of low pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
RESULT: Low pressure switch failed open.
FIX: Check pressure (inches W.C) of low pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
CODE: E224.
RESULT: Low pressure switch failed closed. Refer to troubleshooting.
FIX: Check pressure (inches W.C) of low pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
RESULT: Low pressure switch failed closed. Refer to troubleshooting.
FIX: Check pressure (inches W.C) of low pressure switch closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
CODE: E225.
RESULT: High pressure switch failed open. Refer to troubleshooting.
FIX: Check pressure(inches W.C) of high pressure switch closing on heatcall. Measure operating pressure (inches w.c. Inspect vent and combustion air inducer for correct operation and restriction Resumes normal operation after fault is cleared.
RESULT: High pressure switch failed open. Refer to troubleshooting.
FIX: Check pressure(inches W.C) of high pressure switch closing on heatcall. Measure operating pressure (inches w.c. Inspect vent and combustion air inducer for correct operation and restriction Resumes normal operation after fault is cleared.
CODE: E226.
RESULT: High pressure switch failed closed. Refer to troubleshooting.
FIX: Check operation of high pressure closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
RESULT: High pressure switch failed closed. Refer to troubleshooting.
FIX: Check operation of high pressure closing on heat call. Measure operating pressure (inches w.c.). Inspect vent and combustion air inducer for correct operation and restriction. Resumes normal operation after fault is cleared.
See What Our Customers Are Saying:
Jun 5, 2018
All interactions from sales to installation were Courteous and professional. The installation was seamless and the attention to detail including clean up was outstanding. I highly recommend TwinTech Heating and Cooling.
May 17, 2018
Twintech's Salesman Dave arrived promptly was friendly and courteous, listened and assured us the installation would be completed according to our requests. The crew arrived early morning on May 11th, 2018 and worked through till late afternoon non-stop. They were very friendly, very professional, their expertise was excellent, their workmanship outstanding and the installation was completed in a timely and efficient manner. We were completely satisfied and happy with the quality of the work.
May 9, 2018
I had cold and hot spots all over my 70 yr old home. My furnace is quite new and Greg optimized the fan and furnace. The original installer just took it out of the box with factory settings and installed it- basically running at 50% of capacity. Greg also routed heat into my laundry room, yeah - so now I can renovate laundry room - thanks Greg. He is honest, professional and knowledgeable. I will be calling him back in the spring to optimize my AC as well.
May 8, 2018
Wonderful from beginning to end. I tend to fret and worry about home improvements but the excellent team at TwinTech put my mind as ease. They listen, they are patient and best of all ... the work they did is amazing! I chose the Goodman 80K BTU 2 stage furnace and the matching Goodman air conditioner. Greg, Grant and Poitr "Peter" arrived on time, took great care, explained everything to me and they answered all of my questions. They carefully adjusted the factory settings to optimize the furnace for my house and they also checked the duct work in the basement. Dave, the Sales Manager, came by to say "hello" and to see if I was happy. YES, I am happy with the work! The furnace is very quiet. I have it running on low just to circulate the air in the house and it's so much quieter than my old furnace. When I need new duct work for an upcoming basement renovation TwinTech will be my first choice. I highly recommend TwinTech. PS. They were even nice to my dogs.
Apr 21, 2018
Greg was prompt on the scheduled day of installation and the work was done well within the time estimated beforehand. Installation was neat and the equipment and scope of work was as specified in the quote. One item I must point out is that we were faced with a "No Heat" situation the day before the scheduled installation and Greg came out to address it free of charge. Not only that, but he also corrected an installation fault with our smart thermostat that was not part of the original job, again free of charge.
Mar 16, 2018
Greg came by to do a routine furnace checkup. He was very knowledgeable and professional, letting me know what's being checked/adjusted and giving me tips to ensure everything runs smooth. Very honest and upfront about what's working fine vs. what may need to be fixed/replaced. He didn't attempt to up sell anything that wasn't necessary. I'm glad to have finally found someone I can trust and rely on for all my HVAC needs - furnace, A/C, and hot water tank.
Mar 4, 2018
I'm very happy with the work that was done. Everyone from salesperson to the installers were friendly and professional. They were on time and cleaned up the job site after it was installed. They also answered all my follow up questions promptly. I wouldn't hesitate to work with them or recommend them again.
Feb 28, 2018
Thanks to the team at Twin Tech for a great job installing my new heat pump/ac unit. The guys were very polite and professional. When they left you would never have known they had been there except for the new Mitsubishi unit on the wall!! would highly recommend the Twin Tech team.
Feb 28, 2018
Installed professionally, no delays, no rework needed. Very reliable contractor and sales person. Also installed BBQ gas line and some duct work.
Feb 19, 2018
Greg and Grant are friendly, reliable, and knowledgeable HVAC professionals. The twins, Dave and the entire team provided efficient top quality service. Our family plns to use Twintech for all of our future HVAC needs.
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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