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:
Feb 13, 2019
Fantastic team. Completed the job as per the specifications and in under 3 hours. Highly recommended Twintech.
Jan 30, 2019
During the summer, I previously hired TwinTech to replace my air conditioner when it failed. They did an excellent job so when I decided to proactively replace the furnace I contacted them. The furnace I had was 22 years old and showed signs of internal leakage. It still worked but rather than wait to have it fail in cold weather, I decided to purchase a higher efficiency model before it failed and take advantage of energy efficiency rebates. TwinTech offered very useful advice on the make and model of furnace to choose including high efficiency and variable speed motor. The price was reasonable, TwinTech arrived at the allotted time, installed the new furnace (including some re-routing of exhaust lines since the existing ones were too close to other vents), removed the old furnace, tested the installation and cleaned everything up. Overall, it was a good experience, they did a great job and the new furnace is working well.
Jan 26, 2019
Greg came over at 9:30pm to rescue my daughter and I from a horrible experience with Enercare that evening. He was professional. Kind. And got us what we needed quickly and at an afford price. I would 100% recommend calling on Greg and his team for any of your heating and cooling needs in the future!!
Jan 24, 2019
Installed a great hot water heater when our old one failed. When my furnace died during cold weather they showed up quickly and my house was warm before my wife got home. :)
Jan 14, 2019
I dont usually right reviews but when you receive service like this I felt it was a must. Honest and fair. I Have 4 children and on Xmas eve my furnace stopped working and a gentleman came out and got me up and running so at least we would have heat for the holidays. As promised he would replace my furnace early in the new year. The job was completed on time, great price for quality furnace and extremely clean and professional job. Would have never known anyone was in the house. Not a spec of dust or mess from lugging out an old rusty furnace. If you have any ac or heating concerns twintech is your only option. I was royally impressed with and Im sure you will be too.
Jan 14, 2019
Class Act ! These guys were professional right from the quote stage through to installation. They know their stuff and took their time to help educate me. They take pride in their work and it shows. I would recommend TwinTech Heating and Cooling to anyone. Keep up the great work !!!
Dec 28, 2018
This Company is terrific. No high pressure sales and they deliver exactly what they promise to deliver. The new furnace is great and we now get consistent temperatures throughout the house. The installers were great and very efficient and completed the work on schedule on the promised day. Everyone representing this company was very aware of their presence in our house and worked diligently to keep our home as uninterrupted and as clean as was humanly possible. We did not need to go around the house to clean up after they left, what a nice surprise. We have had follow up by the company to ensure everything is to our satisfaction. How unusual in today's environment. The impression left by Twintech is that they care about us and our home. This is so refreshing in today's high tech world. Out thanks go out to Dave in sales and G, G, and P (the installers).
Dec 21, 2018
They were Timely and professional. They were very Knowledgeable with answering all of my questions.
Dec 23, 2018
The entire process was prompt and professional, from the initial quote to the installation of the new furnace. The team installed the new furnace and removed the old one in approx. 4 hrs. The guys were very knowledgeable and gave me lots of information. I have used Twintech before for a new A/C installation and new I was in good hands.
Dec 9, 2018
The overall experience dealing with this company was great from start to finish when getting a new furnace and ac this year. Everything was clearly explained to us during our consultation with Dave and there were no surprises with added costs. The work was done as expected and their response time to inquiries were very timely generally within a few hours or less. They are all very professional and was a pleasure to do business with them. Highly recommend to anyone looking for honest quality professional service.
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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