$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 Private User on Twintech Heating and Cooling

Our hot water tank died and with an after hours phone called Bob the sales guy jumped into action. Friendly, courteous and genuinely wanted to do whats best for our house hold we were given options and he awaited an answer with no pressure.

We decided on what we wanted and it was installed asap and Greg and team worked and cleaned up so well, you would never know there was a hot water tank there before!

We love our hot water tank and being able to have back to back to back showers without having to wait for the hot water tank to heat the water!

by Gary Grieves, Ajax on Twintech Heating and Cooling

I had heard of Twin Tech from a good friend of mine.
I needed to get a new Air Conditioner. It was not working properly and was 19 years old. I decided to get a new furnace at the same time.
I gave them a call on Saturday June 28.
I spoke to Bob Graham. I made arrangements for him to attend my house the following day.
I saw him on Sunday June 29 at 1100 AM.
He was on time and looked professional.
He spent 2 hours with me going over what I needed. He also suggested that I purchase a Humidifier. He gave me a quote of just under $11,000.00 for the purchase and installation of a Air Conditioner, Furnace and Humidifier. He was not pushy and gave me time to speak to my wife.
I called Bob on Monday June 30 and made arrangements to have it installed by the end of the week.
On Friday June 3 they arrived at 830 AM.
Again, right on time.
Greg and Mitch worked all day and finished the installation by 430 PM.
They made sure that everything was working properly and the basement was just as clean as it was before they came.
I will now be using Twin Tech to perform any maintenance needed on this equipment.
I was completely satisfied from start to finish with the service provided.

Thank You,
Gary Grieves.
Upchurch Ave.
Ajax.

by Kevin, Toronto on Twintech Heating and Cooling

We contacted TwinTech after having another ductless air-conditioning company come in to quote on a solution for our townhouse. We had a unique problem where my office was a hot spot - it's at the front of the unit and gets a lot of sun. If it's 20C outside, It's 29C in my office. The other company could not build a solution that would get a ductless unit to that room because of the location - the AC unit would have to be at the rear, and ductless systems would have to be on that side of the interior. TwinTech suggested a hybrid solution to fit our unique problem, where the ductless unit would move cold air to an air exchanger installed in our bedroom closet, and then they built a ducted vent system between all the upper rooms. This was less intrusive than building a central air system, and less expensive. Each room has a vent that I can close off, so I can push more cold air to my office when needed. We really didn't want ductless units sitting on the walls, and this looks and works better. I really appreciate the extra thought and care that went into the design of a solution, and the attention to detail in the installation. They answered all of our questions, and were able to do a bit extra by installing the ducts around the vents and painting them for us. It cost more than we originally planned for, due to our unique needs, but the fact that they offered financing helped us budget for more.
The job was done fast (I think we got lucky with timing where it wasn't the AC install busy season yet), and the team was very friendly and professional. They arrived and finished each day when they said they would. My office is now running at a comfortable temperature! I'm extremely happy with the experience and would whole heartedly recommend them.

by Private User on Twintech Heating and Cooling

How lucky are we to have this team come save us from our broken down, under sold, poorly installed previous unit (mind you there is a reason SEARS went bankrupt). Bob arrived on time to give us a detailed review of our unit and furnace; very knowledgeable. Greg arrived as planned with the new unit and reiterated what Bob explained how our furnace is equipped to handle the new unit and we didnt need to spend more money on a variable speed air conditioner. Cant say enough on how professional, efficient and personable this team is. Thank you so much guys!

by Private User on Twintech Heating and Cooling

We used Twintech for our replacement AC. Bob did a great job assessing what we needed and organized the install and showed up on install date. Greg and Mitch were on time and were very neat. They covered the traffic areas with a drop cloth and did an excellent install. Great clean up after install complete. Would recommend Twintech for heating and cooling.

by Private User on Twintech Heating and Cooling

They were fantastic, clean, freindly, great service. Would definitely recommend. Answered ally questions and more.

by Private User on Twintech Heating and Cooling

We woke up at about 7 a.m. the Sunday morning before Valentine's Day to a house that was barely 15 degrees Celsius on a really cold day. We tried to call some other suppliers but no answer or call back. We did a quick google search and Twintech came up. Had never dealt with them before. They had a chat line and lo & behold, someone answered; Greg. Helped us diagnose that our 40 year old furnace pilot light was out and walked us through how to relight it. All worked well; he even called me during this process. No charge I was told when asked.
15 minutes later, the pilot went out. It would not stay lit. Greg had Bob call us and we set up a meeting for about 11 a.m. that same Sunday.
Bob walked us through the options and even brought 3 electric space heaters for us to use. By Tuesday afternoon, we had a new Furnace and central air installed.

The team was helpful, responsive and respectful. Very glad we found them by accident and looking forward to a nice cool summer after a warm winter.

Thanks guys!

by Furnace And Humidifier Install on Twintech Heating and Cooling

Dealing with Bob and the installation crew was a pleasure. They took the time to explain everything. What would benefit us the most and the price difference. They were in and out in a reasonable time frame and fit us in within a couple days of original meeting. Quality of work is excellent as well.

by Private User on Twintech Heating and Cooling

A pleasure dealing with Bob ,Spencer and Mitch . They are professional and they also observe the covid 19 precautions . Bob explained the whole process and got the new furnace up the next day . Highly recommend

by Gary Monson, Ajax on Twintech Heating and Cooling

Would like to thank TwinTech for their quick response to our furnace repair. We used TwinTech to install a new furnace and AC a few years
back. Our furnace started to have problems early in the evening of extremely cold night. Contacted TwinTech and they were able make a service call later that evening. They got the furnace going and came the next day to replace a part. The part was under warranty and there was
no charge for either service call!
We are extremely happy with their customer service and would highly recommend them.
Gary & Kelly

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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