Durham Region Air Conditioning Repair, Service and Installation
The flashing LEDs on your furnace will correspond to a specific fault code that is shown here on their diagnostic chart.
Each of the following status codes is a two digit number with the first digit determined by number of flashes of the YELLOW L.E.D. and the second digit determined by number of flashes of the GREEN L.E.D.
If status code recall is needed, do not remove power or blower door. Briefly remove and then reconnect one main limit wire to display stored status code.
To initiate the component test sequence, shut OFF the room thermostat or disconnect the "R" thermostat lead. Briefly short the TEST terminal to the "COM24V" terminal. Status LED will flash code and then turn ON the inducer motor. The inducer motor will run for the entire component test. The hot surface ignitor, blower motor-heat speed and blower motor-cool speed will be turned ON for 10-15 seconds each. Gas Valve and humidifier will not be turned on.
CODE: CONTINUOUS OFF
RESULT: Check for 115VAC at L1 and L2, and 24VAC at SEC-1 and SEC-2
RESULT: Check for 115VAC at L1 and L2, and 24VAC at SEC-1 and SEC-2
CODE: CONTINUOUS ON
RESULT: Control has 24VAC power
RESULT: Control has 24VAC power
CODE: RAPID FLASHING
RESULT: Line voltage (115VAC) polarity reversed.
FIX: If twinned, refer to twinning kit instructions.
RESULT: Line voltage (115VAC) polarity reversed.
FIX: If twinned, refer to twinning kit instructions.
CODE: 1-1
RESULT: NO PREVIOUS CODE
FIX: Stored status codes are erased when power (115VAC or 24VAC) to control is interrupted or 48 hours after each fault is cleared.
RESULT: NO PREVIOUS CODE
FIX: Stored status codes are erased when power (115VAC or 24VAC) to control is interrupted or 48 hours after each fault is cleared.
CODE: 1-2
RESULT: BLOWER ON AFTER POWER UP (115VAC or 24VAC)
FIX: Blower runs for 90 seconds, if unit is powered up during a call for heat (R-W closed)
RESULT: BLOWER ON AFTER POWER UP (115VAC or 24VAC)
FIX: Blower runs for 90 seconds, if unit is powered up during a call for heat (R-W closed)
CODE: 1-3
RESULT: LIMIT OR FLAME ROLL-OUT SWITCH LOCKOUT
FIX: Control will auto reset after 3 hours. Reset switch or replace fuse link.
RESULT: LIMIT OR FLAME ROLL-OUT SWITCH LOCKOUT
FIX: Control will auto reset after 3 hours. Reset switch or replace fuse link.
CODE: 1-4
RESULT: IGNITION LOCKOUT- Control will auto-reset after three hours.
RESULT: IGNITION LOCKOUT- Control will auto-reset after three hours.
CODE: 2-1
RESULT: GAS HEATINGING LOCKOUT
FIX: Control will NOT auto reset. Check for: *Mis-wired gas valve *Defective control (Valve relay)
RESULT: GAS HEATINGING LOCKOUT
FIX: Control will NOT auto reset. Check for: *Mis-wired gas valve *Defective control (Valve relay)
CODE: 2-2
RESULT: ABNORMAL FLAME-PROVING SIGNAL
FIX: Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared. Check for: *Leaky gas valve *Stuck open gas valve
RESULT: ABNORMAL FLAME-PROVING SIGNAL
FIX: Flame is proved while gas valve is de-energized. Inducer will run until fault is cleared. Check for: *Leaky gas valve *Stuck open gas valve
CODE: 2-3
RESULT: PRESSURE SWITCH DID NOT OPEN
FIX: Check for: * Obstructed pressure switch *Pressure switch stuck.
RESULT: PRESSURE SWITCH DID NOT OPEN
FIX: Check for: * Obstructed pressure switch *Pressure switch stuck.
CODE: 2-4
RESULT: SECONDARY VOLTAGE FUSE IS OPEN
FIX: Check for: *Short circuit in secondary voltage (24VAC) wiring.
RESULT: SECONDARY VOLTAGE FUSE IS OPEN
FIX: Check for: *Short circuit in secondary voltage (24VAC) wiring.
CODE: 3-1
RESULT: PRESSURE, DRAFT SAFEGUARD, AUX-LIMIT SWITCH (when used*) OR BLOCKED VENT SWITCH (when used) DID NOT CLOSE OR REOPENED (DOWNFLOW ONLY)
FIX: If open longer than five minutes, inducer shuts off for 15 minutes before retry. Check for: - Proper vent sizing - Defective inducer motor - Low inducer voltage (115VAC) - Defective blower motor or capacitor - Restricted vent - Excessive wind - Defective pressure switch - Inadequate combustion air supply - Disconnected or obstructed pressure tubing If it opens after trial for ignition period, blower will come on for 90 second recycle delay,
RESULT: PRESSURE, DRAFT SAFEGUARD, AUX-LIMIT SWITCH (when used*) OR BLOCKED VENT SWITCH (when used) DID NOT CLOSE OR REOPENED (DOWNFLOW ONLY)
FIX: If open longer than five minutes, inducer shuts off for 15 minutes before retry. Check for: - Proper vent sizing - Defective inducer motor - Low inducer voltage (115VAC) - Defective blower motor or capacitor - Restricted vent - Excessive wind - Defective pressure switch - Inadequate combustion air supply - Disconnected or obstructed pressure tubing If it opens after trial for ignition period, blower will come on for 90 second recycle delay,
CODE: 3-3
RESULT: LIMIT OR FLAME ROLL-OUT SWITCH IS OPEN
FIX: If open longer than 3 minutes, code changes to lockout #13. Flame roll-out switch requires manual reset. Check for: - Defective blower motor or capacitor - Dirty filter or restricted duct system - Loose blower wheel - Defective switch or connections - Inadequate combustion air supply (Flame roll-out switch or fuse link open) - Open Flame Roll-out Switch or fuse link. Manual reset or replace.
RESULT: LIMIT OR FLAME ROLL-OUT SWITCH IS OPEN
FIX: If open longer than 3 minutes, code changes to lockout #13. Flame roll-out switch requires manual reset. Check for: - Defective blower motor or capacitor - Dirty filter or restricted duct system - Loose blower wheel - Defective switch or connections - Inadequate combustion air supply (Flame roll-out switch or fuse link open) - Open Flame Roll-out Switch or fuse link. Manual reset or replace.
CODE: 3-4
RESULT: IGNITION PROVING FAILURE
FIX: Control will try three more times before lockout #14 occurs. If flame signal lost during blower on-delay period, blower will come on for 90 second recycle delay. Check for: - Control ground continuity - Flame sensor must not be grounded - Oxide buildup on flame sensor (clean with fine steel wool) - Proper flame sense microamps (.5 microamps D.C. min., 4.0 - 6.0 nominal). - Gas valve defective or gas valve turned off - Manual valve shut-off - Defective Hot Surface Ignitor - Low inlet gas pressure - Inadequate flame carryover or rough ignition - Green wire MUST be connected to furnace sheet metal.
RESULT: IGNITION PROVING FAILURE
FIX: Control will try three more times before lockout #14 occurs. If flame signal lost during blower on-delay period, blower will come on for 90 second recycle delay. Check for: - Control ground continuity - Flame sensor must not be grounded - Oxide buildup on flame sensor (clean with fine steel wool) - Proper flame sense microamps (.5 microamps D.C. min., 4.0 - 6.0 nominal). - Gas valve defective or gas valve turned off - Manual valve shut-off - Defective Hot Surface Ignitor - Low inlet gas pressure - Inadequate flame carryover or rough ignition - Green wire MUST be connected to furnace sheet metal.
See What Our Customers Are Saying:
May 16, 2021
Appreciated a quick response to my request. Dave and Greg were very professional and made the experience seamless.
Feb 1, 2021
Very professional through the entire process. Installation and removel was done on a sloppy winter day, they put down runners on the floors and stairs and when they left, there wasn;t any sign of someone being in our house. Furnace works great as promised.
Feb 1, 2021
Dave was very pleasant to deal with and Twintech responded quickly when our furnace needed to be replaced ASAP. Installation was done on time and the crew were neat and tidy. We now have a great furnace that suits the needs of our family.
Feb 1, 2021
When your furnace kicks in over the holidays and you're not sure where to turn.. I'm so thankful that this company returned my phone call. I appreciated their transparency and clarity which allowed me to make an informed decision. With various quotes thrown at you, it can be difficult to make the right decision and trust the solutions offered by different companies. TwinTech spoke the truth and delivered on their word. Neat, timely and clean service; the peace of mind I needed during a very cold holiday season. I highly recommend them!
Feb 1, 2021
Pulling a old unit out and installing a modern heating system! Required drilling holes in the wall for the newer pipes. We went from 70% (I am willing to bet it was far less due to lack of maintenance and just old) to 96% newer . It now feels warmer and more pressure and we use to run extra heaters and feel as though they are not necessary!
Feb 1, 2021
I received three quotes before deciding to choose Twintech. Dave's prices was much more reasonable than the competitors. I most appreciated their honest recommendations. Others tried to oversell their products and services. Thank you Dave!
Feb 1, 2021
They had the best price and did a great job on the installation. Recommend them to anyone.
Feb 1, 2021
It was a amazing and professional high quality job
Friendly and very helpful representatives
Thank you for understanding my concern
And explain very well
Overall we pleased with your service
Tanks
May 15, 2020
My 19 year old furnace stopped working when the cold weather hit in November, and I was left without heat. I interviewed several companies and found TWINTECH HEATING and COOLING to be very knowledgeable, quick to respond to my inquiries and very competitively priced.
Dave provided all of the information and pricing ahead of time and set up the appointment for the installation. Greg and Mitch arrived on time to do the installation and worked quickly and efficiently to complete the job.
After the completion of the installation, Dave followed up to ensure that everything was working well and that I didn't have any concerns.
Overall, this was a low-stress and flawless experience from start to finish. I would highly recommend TWINTECH HEATING and COOLING to anyone that requires a new furnace.
May 14, 2020
Our 20 year old furnace broke down during the first cold weekend this past November and our usual HVAC company never returned our phone call. Their loss, missing out on a sale since we didn't want to spend much fixing an old furnace and our 40 year old air conditioner was also long overdue for replacement. We proceeded in obtaining three different quotes for furnace and air conditioner replacement, and proceeded with the one we received from Twintech.
Dave was friendly, knowledgable and accommodating to our schedule and provided with us with a price that fell in the middle of the three quotes that we had. We felt that the Amana furnace and air conditioner he quoted us on were the best products and value offered to us and felt most comfortable with the professionalism and reputation of Twintech.
Greg, Grant and Mitch were at our house for installation the day after we decided to proceed. The guys were friendly and informative, the job was completed efficiently and workmanship appears excellent. Our house is certainly much more comfortable with the new two-stage variable speed Amana furnace compared to the old clunker! And, we're looking forward to enjoying the new air conditioner once summer rolls around again. Thanks 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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