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:
Aug 14, 2022
I had them replace my furnace last year. When it came time for the air conditioner this year, I did not hesitate to call Twintech again. I will also have them perform regular maintenance on them.
Aug 13, 2022
We required a new HVAC replacement after running the old
system for 18 years.
Dave understood our requirements and gave us a quote that
covered all the necessary items.
Installation was fast and very tidy. Everything works as
it should. Our thanks to Greg, Mitch and others for their
excellent work. Recommend this family owned business to
anyone else, considering HVAC or other work.
Aug 12, 2022
I needed a new furnace and A/C to replace my 21 yr. old units, and went to the internet to view potential companies in May, I received 3 quotes,
and chose Twintech based on their salesman Dave who was very detailed and covered off everything on what Twintech was all about,
an extremely dedicated company with so many years of experience, and after reading the on line reviews I was sold on Twintech, who did not disappoint as the installation team were top notch with Greg leading,
I would highly recommend this company without any doubts, in my books they are first class all the way. Our new Amana furnace and A/C are working perfectly !
Aug 11, 2022
Flawless transaction. They did exactly what they promised, showed-up on time, cleaned-up, and were highly professional. Highly recommended.
Aug 10, 2022
Salesperson and 2 man installation team were all professional and
knew their stuff. All three were friendly and helpful, answering all
my questions. The quality of their work demonstrated their experience
and expertise in their field.
Aug 9, 2022
A dear late cousin of mine recommended this company and I have been happy with the service.
Aug 8, 2022
We are very pleased with the work done by Twintech. They were very professional from start to finish. Dave came to our home and gave us a very competitive quote for new high efficiency furnace and air conditioner. The installers were very courteous and professional. We would highly recommend them.
Aug 7, 2022
Great experience getting an old furnace replaced.
Sales Guy (Dave) was great - honest, responsive, and friendly.
The work itself was done quickly and we are very happy with the outcome, thank you! We recommend TwinTech!
Aug 6, 2022
This review is late coming so my apologies to the amazing Twin Tech team! I contacted Dave at Twin Tech for a quote this past Feb (as I was collecting a few) and his recommendation was excellent. From the first meeting with Dave to the team installing the new furnace, not once did i feel uncomfortable . The team were extremely professional yet personable and clean and tidy. Decent companies still exist!
The new furnace just purrs and its just amazing the difference it has made!
(PS my sibling ended up getting a furnace from them as well)
Aug 5, 2022
The service was Twintech was excellent.
Dave our salesperson was easy to talk to and was professional. The unit recommended meets our needs and budget.
Greg and his team arrived on time for the installation and even got rid of the garbage the contractors left in our furnace.
Would definitely recommend Twintech.
See What Our Customers Are Saying:
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.
Why Buy a Heat Pump For My Pickering Home
- SUBMITTED BY:
- TWINTECH HEATING & COOLING
- - April 27, 2025
When it comes to keeping your Pickering home comfortable year-round, choosing the right HVAC system is crucial. One of the most efficient and versatile options available today is the heat pump. At Twintech Heating and Cooling, we believe a heat
Read MoreHVAC Thermostat Not Working After Trying to Replace
- SUBMITTED BY:
- TWINTECH HEATING & COOLING
- - August 15, 2023
Today I tried to replace my existing thermostat with a Nest Learning Thermostat. My old thermostat is a Bryant thermostat and Bryant HVAC unit. The thermostat has Y G C W and Rh with a jumper to Rc. Connected the Nest as suggested and got th
Read MoreWhy AC Inspections are Important
- SUBMITTED BY:
- TWINTECH HEATING & COOLING
- - June 18, 2024
Air conditioning (AC) inspections are crucial for several reasons, impacting both the performance of the system and the comfort and health of the occupants. Here are key points highlighting the importance of regular AC inspections: 1. Energy Effic
Read MoreReasons Your AC Might Leak
- SUBMITTED BY:
- TWINTECH HEATING & COOLING
- - March 18, 2024
An air conditioning (AC) unit leaking water can be a sign of various issues. Here are some common reasons why your AC unit might be leaking: Clogged Drain Line: Over time, algae, mold, and debris can accumulate in the drain line, causing it
Read More