Proven technology. Exceptional reliability. Peace-of-mind.

Across Canada, GSW water heaters are recognized for their excellent value, efficiency and reliability. In fact, GSW has more water heaters in Canadian homes than any other water heater manufacturer. GSW earned the trust and loyalty of Canadians by continuing to design and manufacture safer, more dependable electric and energy efficient gas and propane water heaters.

GSW Water Heaters

Power Vent Water Heater

Conventional Vent Water Heater

Electric Water Heater

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The bottom-entry design, available on GSW electric water heater modles, recognized by Natural Resources Canada for exceptional energy savings performance.

GSW line of gas water heaters includes award winning FlameGuard and FlameSafe Safety Systems, the most established and proven technologies on the market for the prevention of flammable vapour ignition.

So it’s with pride in this accomplishment, in innovation and tenacity of all the GSW people who have come before, that we adopted our new positioning “GSW Manufacturing pioneers since 1847″.

GSW believes strongly that the pioneering culture instilled in the company and in their people, will be the key ingredient for their ongoing success in the future – an increasingly non-linear future where only the companies that can continually reinvent, seek new direction and find new ways will thrive.

Can’t find the brand you’re looking for? We carry most Canadian brands, contact us today!

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get total piece of mind with our High Efficiency Furnace and Air Conditioner Rental Program.

Service Area

DeMark Home Ontario servicing area for HVAC-furnaces, air conditioners, heat pumps, hot water heaters, tankless units includes: Toronto, GTA, Vaughan, Mississauga, Brampton, Markham, Scarborough, Milton, Burlington, Niagara Falls, Oshawa, Pickering, Ajax, Aurora, Newmarket, Barrie, Peterborough, Ottawa and more. For a full servicing area please click here.

WE’RE PROUD AUTHORIZED DEALERS OF

Sean Tucker

06:42 26 Sep 24

The response time was very quick from the online request for a new tank. The prices were very competitive and did not have any extra surprise costs even though they did have some extra work that was needed upon arrival. The work that was done was very professional. I went from a gas hot water tank to a tankless one and the model that they installed was great it does take a couple seconds to kick on and heat up the water but the model(RX160IN) installed does enough for multiple uses of hot water at the same time which is much better then their competitions tank for the same price.

Alina Kushnir

01:13 01 Apr 21

Water heater installation. Very highly recommend this company. Mike on the phone and Jason who installed the heater were above and beyond any expectations. Mike helped me with heater selection, explained options and what is the best for my house. Jason arrived right on time and did a great job with the install. Overall 10 stars service from beginning to the end - polite and professional service on the phone and inside my house, easy to reach, clear contract with option to buy out heater at any point of time.

Euro Boutique

05:12 26 Mar 21

The customer service is above and beyond. All your questions are answered without any hesitation. Very professional and great service. I highly recommend DenMark Home Ontario Services, you will not be disappointed.

Ladgar j

05:21 25 Feb 21

I am so thankful to Demark Home. Our furnace stopped working this afternoon & I was afraid our family will be left with no heat for days. Luckily Demark Home managed to squeeze the installation for the same day later in the evening. Eddie and his colleague did a wonderful & clean job. We are really impressed with the speedy service that was done for a reasonable price.

Customer Support

08:21 21 Feb 21

Mike was great at explaining our options and was not pushy like some sales people. The installers John and Dan were great as well, very clean and did a great job with the install. We would definitely recommend Demark Home to anyone who is looking for competent sales and installation of new hvac products. Thank you.

Farid Nasir

21:01 22 Jan 21

Good Service. Very fast response. The technician was efficient and smart. Good price and good correspondence. thank you Mike

Altaf Sahibzada

19:58 12 Nov 20

Good Service. Very fast response. The technician was efficient and smart. Good price and good correspondence.

Rob

23:45 15 Oct 20

Had new hot water tank installed. This company is professional from start to finish. So impressed with people I spoke to on phone and the excellent installer who came to my house. Very careful and responsible when installing water tank. Rates reasonable and written documentation clear and fair. Well done !!

James Brown

13:24 20 Sep 20

They are very easy to deal with no pressure sales good product and excellent service

Cos C

15:15 13 Aug 20

Used the company twice for the replacement of my water heater, and AC installation, very professional, and prompt service. Very knowledgeable. Amazing customer experience.

Grecory Conor

15:50 31 Jul 20

We purchased and installed our new Air Conditioner through Demark. They did an awesome job, quick, clean.. would highly recommend!

Chris Newell

17:11 23 Jul 20

I would give them 6 stars if I could. I had been a long term customer of another, very well recognized provider - who trumpets that they have the largest and best service team in our area - and when my rental water heater began leaking I called their service line and was informed that it would be 4 days until they could send a tech to inspect it. I confirmed that they heard me say that the tank was actively leaking and they apologized for not being able to do anything and immediately starting upselling me on alternate equipment, while confirming that regardless it will be 4 days before anything can or will be done by them. Not being very happy with that I started researching alternate providers and am very happy to have found DeMark. Not only did they have a service tech there the next day, I have a higher quality tank than my existing provider and am paying 20% less a month for it. That does not include that they also gave me 2 months for free (as a new customer) and also took care of removing and returning my existing rental unit for no cost.Aside from quality equipment, and a great price, the contacts that I dealt with (Mike on the phone & Jason the tech) were great to deal with.I had put off dealing with replacing the tank for a while - mainly due to past terrible experiences with my existing provider, who seems to only utilize the term 'care' as part of their name and not part of their practices, but in hindsight I wish I had known how easy, and cost effective, it was for me to change providers, as I would have done so ages ago instead of waiting for the leak to force my hand.

Ngọc Châu Giang Nguyễn

02:49 13 Jul 20

I used to rent AC from Reliance, but then I found out they had been overcharging me the whole time. After that friend referred Mike to me, and he is such a good man with great service. He responds quickly, he sent Eddie, the technician, to replace new AC right after. Eddie was fast and professional. He did such a nice and neat job. Mike offered me a very reasonable price even though my house is 200km away from Toronto.Highly recommend the company.

m Na

00:56 13 Jul 20

Hi, I am very pleased with this company. This is the second time that I am using them. This time I fixed A/C and Water Heater in my parents house. Knowing that older people need an extra comfort zone, these guys went that extra mile to make sure everything is installed clean, professional, and on time, of course with a very reasonable price. I strongly recommend them.

Gerard Penney

20:57 06 Jul 20

They are very professional installers where great . Would recommend them to anybody . Great job

Mary Pog

21:27 06 May 20

We just moved into our brand new home and were shopping around for a AC because it wasnt provided by the builder. We called many companies looking for the best monthly payment and finally we found demark home who gave us a great deal. Installation was done on time and we love the job they done. Thank you to everyone at demark home for their great work.

Amit Farmah

20:12 02 Apr 20

I moved my Water Heater rental from Reliance Home Comfort to DeMark Home Ontario about 5 months back. I had no issues with the Installation process and Billing is working accurately as well. I'm happy to switch my hot water tank rental provider and definitely recommend them to everyone.

Silvana Rosati

05:55 28 Mar 20

My water tank finally died and I had to replace it. I am glad I found this company because I did not want to rent with the major water rental providers again and pay at an outrageous monthly rate. The service from DeMark Homes was top notch from the beginning to the end. They installed the new tank, picked up the old and provided all the necessary paperwork required for the return of the old tank back to Enercare. My monthly rental payment is now at a fair honest price and the charges still appear on my gas bill. I would highly recommend this company!Thanks Mike for everything. Silvana R

Boby S

20:12 29 Feb 20

My family needed an emergency furnace replacement because our old furnace's heat exchanger was cracked. We called Demark very late last night and I was expecting to have to leave a message, but to my pleasant surprise, their live representative, Alex, answered my call and handled my request. I explained to Alex my situation and he was able to book a furnace replacement appointment with one of their technicians for the following morning. The technician, Eddie, was great. He arrived on time and completed the job without any mess and explained to me how to use my new furnace and thermostat. The service was pleasant the whole way through, from my initial phone call to the installation of my furnace. I commend Demark Home Ontario for their exemplary customer service as they exceeded all my expectations and found an ideal solution to my problem. Thank you to Alex, Eddie, and the rest of the team.

Bimala Rani

18:39 29 Jan 20

Probably the best company out there. I've had business with them twice this year, I replaced my water tank and the furnace, Unbelievable reply he even answered my message at 1:00 am and had an installation the day after. It was absolutely …fantastic

Ghalib Fakih

17:59 15 Jan 20

Probably the best company out there. I've had business with Mike twice this year, I replaced my water tank and the furnace, Unbelievable reply he even answered my message at 1:00 am and had an installation the day after. It was absolutely amazing quality, service and price. Contractor that came to the house was super nice knowledgeable, and mainly very clean. I will defiantly recommend DeMark Home Ontario to any friend, family, or friend.

Tran Tran

19:04 19 Jun 19

Excellent same day service! Very clean & fast service from removal of the old water tank in the basement to installation new tankless rinnai. Their team is professional, friendly and reliable. I strongly recommend Demark home ontario.

mike rer

04:02 08 Mar 19

My family just got a new furnace installed by Demark Home Ontario. Their technician David did an excellent job. No complaints. The price was very reasonable as well. We chose to sign up for the rent to own program. Thanks again, Demark. I’ll recommend your services to my friends and neighbours.

Rent to own Furnace Program

Rent to own Air Conditioner Program

Rent to own Furnace Program

Rent to own Air Conditioner Program

Rent to own Furnace Program

Rent to own Air Conditioner Program

GSW Water Heaters

GSW Water Heaters

Easy Rentals...

Service Area

WE’RE PROUD AUTHORIZED DEALERS OF