$49 / month O.A.C Including Install
$49 / month O.A.C Including Install

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Durham Region Air Conditioning Repair, Service and Installation

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McQuay was established in 1933. She specialized in the supply and service of air conditioning, ventilation and heating equipment, as well as in the production of heating equipment - heat exchangers and radiators.


McQuay Furnace error codes are seen in three colors, red, green, and amber/yellow. Each color will also flash a specific number of times to signify a specific error. Breaking down each color, and number of flashes, will help you solve the problem you are having with your York Furnace.


CODE: SLOW GREEN FLASH
RESULT: Normal operation

CODE: SLOW AMBER FLASH
RESULT: Normal operation with call for heat

CODE: RAPID RED FLASH
RESULT: Twinning error, incorrect 24V phasing.
FIX: Check twinning wiring. Flame sense current is below 1.5 microamps

CODE: RAPID AMBER FLASH
RESULT: Check and clean flame sensor. Check for proper gas flow. Verify that current is greater than 1.5 microamps at flame current test pad.

CODE: 4 AMBER FLASHES
RESULT: The control is receiving a "Y" signal from the thermostat without a "G" signal, indicating improper thermostat wiring.

CODE: 1 RED FLASH
RESULT: This indicates that flame was sensed when there was not a call for heat.
FIX: The control will turn on both the inducer motor and supply air blower. A gas valve that leaks or is slow closing would typically cause this fault.

CODE: 2 RED FLASHES
RESULT: This indicates that the normally open pressure switch contacts are stuck in the closed position.
FIX: The control confirms these contacts are open at the beginning of each heat cycle. This would indicate a faulty pressure switch or miswiring. This indicates the normally open pressure switch contact did not close after the inducer was energized.

CODE: 3 RED FLASHES
RESULT: This could be caused by a number of problems: faulty inducer, blocked vent pipe broken pressure switch hose or faulty pressure switch.

CODE: 4 RED FLASHES
RESULT: This indicates that the main limit switch has opened its normally closed contacts.
FIX: The control will operate the supply air blower and inducer. This condition may be caused by: dirty filter, improperly sized duct system, incorrect blower speed setting, incorrect firing rate or faulty blower motor. Also, this fault code could be caused by a blown fuse located on the control board.

CODE: 5 RED FLASHES
RESULT: This fault is indicated if the normally closed contacts in the rollout switch opens.
FIX: The rollout control is manually reset. If it has opened, check for proper combustion air, proper inducer operation, and primary heat exchanger failure or burner problem. Be sure to reset the switch and cycle power (24 VAC) to the control after correcting the failure condition. Also, this fault code could be caused by a blown fuse located on the control board.

CODE: 6 RED FLASHES
RESULT: This indicates that after the unit was operating, the pressure switch opened 4 times during the call for heat.
FIX: If the main blower is in a "Delay on" mode, it will complete it, and any subsequent delay off period. The furnace will lock out for one hour and then restart.

CODE: 7 RED FLASHES
RESULT: This fault code indicates that the flame could not be established. This no-light condition occurred 3 times (2 retries) during the call for heat before locking out.
FIX: Low gas pressure, faulty gas valve, dirty or faulty flame sensor, faulty hot surface ignitor or burner problem may cause this. The furnace will lock out for one hour and then restart.

CODE: 8 RED FLASHES
RESULT: This fault is indicated if the flame is lost 5 times (4 recycles) during the heating cycle.
FIX: This could be caused by low gas pressure, dirty or faulty flame sensor or faulty gas valve. The furnace will lock out for one hour and then restart.

CODE: 9 RED FLASHES
RESULT: Indicates reversed line voltage polarity or grounding problem.
FIX: Both heating and cooling operations will be affected. check polarity at furnace and branch. Check furnace grounding. Check that flame probe is not shorted to chassis.

CODE: 10 RED FLASHES
RESULT: Flame sensed with no call for heat.
FIX: Check gas valve and gas valve wiring This indicates that a primary or auxiliary limit switch has opened its normally-closed contacts and has remained open for more than five minutes.

CODE: 11 RED FLASHES
RESULT: This condition is usually caused by a failed blower motor or blower wheel.
FIX: Cycle power (24 VAC) to the control to reset the hard lockout condition after correcting the failure condition.

CODE: 12 RED FLASHES
RESULT: This code indicates an open igniter circuit.
FIX: This could be a disconnected or loose wire or a cracked or broken igniter.

CODE: STEADY ON RED
RESULT: Control failure.
FIX: Replace control board.

CODE: 60-MINUTE AUTOMATIC RESET FROM LOCKOUT
RESULT: This control includes a "watchdog" type circuit that will reset from a lockout condition after 60 minutes. Operational faults 6, 7, 8 will be reset. This provides protection to an unoccupied structure if a temporary condition exists causing a furnace malfunction. An example would be a low incoming gas supply pressure preventing unit operation When the gas pressure is restored, at some point the "watchdog" would restart the unit and provide heat for the house.

CODE: IGNITION CONTROL FLAME SENSE LEVELS
RESULT: Normal flame sense current is approximately 3.7 microamps DC Low flame signal warning starts at 1.5 microamps. Low flame signal control lockout point is 0.1 microamps DC.


See What Our Customers Are Saying:

by JLH from Pickering on Twintech Heating and Cooling

Imagine, it's 5 minutes after the midnight countdown New Year's eve and the furnace quits. We called TwinTech fully expecting to leave a message and actually spoke with Greg, one of the owners! We had an immediate repair early the next morning & a new furnace within the week. We have entrusted TwinTech with all our home HVAC service needs for over 6 years. That's why this week with an opportunity to purchase a new BBQ, we called them 1st to see about a gas line install. It's chicken on the grill tonight! They are efficient, reliable, honest, hard working, and -- attentive is an understatement.

by Curtis, Ajax on Twintech Heating and Cooling

Wonderful customer service, starting from the job quote (Dave), to the clean install, to the follow-up. Twintech is a small company which installed my Napoleon furnace, A/C, John Wood tank, and ran the line for my gas dryer. The installation was completed as promised in one day. The work area was kept very clean, and they even took care of my old rental tank. The professionalism and wonderful customer service is second to none. They completed all of my rebate paperwork, and now I'm getting $2000 back! You will not be disappointed if you hire this company for your project.

by Roy in Pickering on Twintech Heating and Cooling

I was referred to Twintech by a neighbour and was not disappointed. Not only was the customer service excellent their workmanship was second to none. Greg and Grant work extremely clean covering the pathway to the furnace room, labeling the essential parts, left the area spotless and were efficient. They cleaned up the mess left by the previous installers (wiring, improperly installed AC coil, and gaps in venting etc). They also ran through the operation of the new furnace and gave me some maintenance tips. Greg and Grant are professional and all around good guys. I will definitely recommend their service to anyone without hesitation.

by Peter Buck, Pickering on Twintech Heating and Cooling

Very satisfied with service from Twintech , beginning with all the information provided by Dave , which helped make the decision much easier . Installation was very smooth & done on time as promised & cleanup was well done . Would definitely recommend this company & use them again for any future needs . Well done.

by Angela from Ajax on Twintech Heating and Cooling

Twintech Heating & Cooling Inc. came in and replaced my 39 year old furnace with a beautiful Napoleon variable high efficiency furnace! Their work was efficient and professional and they were a pleasure to deal with, from sales to installation! I would highly recommend them.

by Scott and Sandra in Ajax on Twintech Heating and Cooling

After receiving numerous quotes to replace my old furnace and AC unit (which was 20 years old) I went with Twintech. Dave, in sales, answered questions professionally and promptly and worked diligently in order to secure my business. Installation was scheduled the week after and Greg and Peter showed up, as scheduled, and did a fine job installing both units. The site was left tidy and neat. I would highly recommend Twintech for your furnace and AC work.

by Linda from Whitby on Twintech Heating and Cooling

I chose TwinTech because they installed my new furnace a few years ago and did a great job. When they installed my new A/C, they replaced all parts -- the copper pipes, the housing on top of the furnace and the wiring. (Apparently, the wiring for my old A/C was insufficient.) Their pricing was competitive. The sales representative came to see me within a few hours of my call. My new A/C was installed a few days later and I couldn't be happier with Twintech's professionalism and work. I would recommend TwinTech to any homeowner.

by george polychronis from Whitby on Twintech Heating and Cooling

Had a great experience with this company. Great price and great customer service. You wont be disappointed with twintech. Discussed the job with Greg while he was installing who was extremely informative and obviously enjoys the work he does.

by Nuzio in Markham on Twintech Heating and Cooling

I needed my AC unit relocated due to upcoming landscape work. I reached out to the Twintech team through Homestars. Dave connected with me immediately to discuss the project and various options. We decided the best option was to mount the unit on the wall. Greg was in touch with me the same day as well and we scheduled the work for later that same week. This was a small job so I did not think I would get immediate attention. The Twintech team exceeded my expectations in every respect. They were very knowledgeable and friendly. The team arrived exactly on time on the scheduled day and worked efficiently to get the job done quickly. I would definitely use Twintech again for any Heating and AC projects.

by Leslie B, Pickering on Twintech Heating and Cooling

I have used Greg Dainty for over 15 years in 3 different homes, for heating, cooling, pool heaters, appliances and bbq lines. Greg has always been so professional, friendly and the workmanship nothing short of fantastic. Greg has always discussed my options and fixing versus replacing, giving his honest opinion and what works best for me cost effective wise and long term. I have valued his opinion so much and have not trusted my gas needs with anyone since using him. I have also referred him to many of my friends and family and have always been so thankful with how well and quickly he looks after us all. I hold Greg in the highest regard and would recommend him to anyone with complete confidence!

See What Our Customers Are Saying:

by Aaron on Twintech Heating and Cooling

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.

by Linda on Twintech Heating and Cooling

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!

by Robert Rogers on Twintech Heating and Cooling

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.

by Robert Mizuno on Twintech Heating and Cooling

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!

by Ruth on Twintech Heating and Cooling

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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