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:
Jul 28, 2022
On coldest night of the year our furnace quit. At 8:40 in the morning Greg arrived and gave us a diagnosis and a recommendation. By 2:30 we had a new furnace and were warm again. Great company. Great customer service. Good reasonable price.
Peter, Pickering
Jul 3, 2022
Twin tech team was very efficient and prompt. They provided a quote within hours of request and got the job done on time. No disruption to home function. We would highly recommend this team. Job well done.
Jul 3, 2022
Our furnace bit the dust, and Twintech came out to troubleshoot and diagnose the problem within a couple of hours. Mitch was super helpful, patient, and answered all of our questions. When we decided to get the furnace replaced, the crew was over first thing the next morning and did a fantastic job. Not only did they complete the job in a few hours, but they cleaned up and respected our house as they went, and answered all of our follow-up questions. I've used Twintech for our HVAC needs in the past and will continue to do so. I'd recommend them to anyone, and it feels good to support a local, family-owned business.
Jul 3, 2022
Dave and the Twintech team were fabulous from day 1 and helped us through the process to identifying a new furnace and AC unit. This was our first time through this process and Dave did a thorough job explaining all the components and was very patience answering all our questions. Dave provided great insights and fair pricing.
The Twintech team did an awesome installation. Very clean and efficient. I would highly recommended their service.
Jul 3, 2022
We had a new Amana furnace installed by Twintech and we were very pleased with the installation. It is nice to have a warm house again.
Jul 3, 2022
Excellent job. Excellent service. Competitive price. Its rare to find a company with the knowledge and professional results we have experienced with Twintech. The clean and neat installation with attention to detail and drop sheers to respect our property is a clear indication of Twintechs high level of integrity. The 1-1/2 gas line upgrade they did for our pool 3 years ago was awesome. Can't say enough. Thank-you Twintech.
Jul 3, 2022
Twitch did a great job with the installation of our new furnace. I really appreciated their honesty and I could trust what they were telling me. Another company tried to suggest significantly more work at a greater cost claiming it was necessary to meet current building code. Twintech is very fair. All staff I meet were friendly, polite and trustworthy. I would recommend Twitch for a furnace.
Jul 3, 2022
This is a professional team that's easy to deal with. I would strongly recommend them
Jul 3, 2022
Very professional firm from start to finish!
They removed the old oil tank and furnace. They installed air conditioning and a new propane furnace.
Professional installation, on time and no mess.
Very pleased with their work and would highly recommend the company. Our house is three stories so they spent the time to do all the calculations to make sure we would have great performance on each floor.
Thank you again!
Jul 3, 2022
Upon a routine yearly maintenance, it was discovered there was a leak in the heat exchanger and a I needed a new furnace. I know nothing about these things and was completely stressed out. The company I had the maintenance plan with quoted me a huge number to rent a furnace, I just wanted to cry. Then I spoke to Dave at Twintech. He was so knowledgeable and calming, provided me a fair quote and within a few days I had an amazing crew show up to my house and install my new energy efficient furnace! I have already recommended these wonderful people at Twintech to a good friend of mine. Thank you Twintech!!
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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