Reliable Tankless Water Heater Repair Service in GTA

At HVAC Group, we provide fast, reliable tankless water heater repair across the GTA. Whether you have no hot water, low pressure, or error codes, our certified technicians quickly diagnose and fix the issue. We service all major brands with same-day emergency repairs whenever you need.

Newly installed Navien tankless water heater in a basement, providing energy-efficient hot water
Newly installed Navien tankless water heater with exposed internal components, ensuring energy-efficient hot water supply

Hot Water Anytime

Same-Day Tankless Water Heater Repair – Serving the Entire GTA!

A failing tankless water heater can disrupt your daily routine. That’s why we offer 24/7 emergency water heater repair services across the GTA. Whether it’s low water pressure, ignition failure, or mineral buildup, our expert technicians provide quick diagnostics and lasting repairs. We restore hot water fast, ensuring your system runs efficiently and reliably.

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5.0
Based on 216 reviews
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michael wickeler profile picture
michael wickeler
16:50 06 Aug 25
HVAC GROUP punctual and very efficient at their job. Figured out the problem quickly and fixed the Air conditioner.
Erica Larry profile picture
Erica Larry
22:45 01 Aug 25
Amazing service from Yuri! We will be using you again in the near future. Thank you again.
Max Peters profile picture
Max Peters
15:47 31 Jul 25
Yuri and team quickly diagnosed my A/C issue and had the system back and running, with a very quick response time. Would recommend to anyone.
Dave Neeb profile picture
Dave Neeb
16:03 30 Jul 25
Excellent and thorough, great pricing. Thanks again.
John Hamilton profile picture
John Hamilton
19:58 25 Jul 25
The HVAC Group did a fantastic job restoring our broken AC . Quality professional workmanship at a fair price .We will definitely call them back next time .
Katie Ogiba profile picture
Katie Ogiba
01:17 25 Jun 25
HVAC Group came recommended by a friend when our AC stopped working on a 38 degree day. We had called other services and either couldn't get through or everyone was booked. When I spoke to Yiri he said it was so busy they were booked until next week (which I expected as every other place said the same thing). But he stayed on the phone to ask a few questions about the unit. He was kind, and you can just tell when someone actually cares - he didn't have to talk me through the possible issues etc. He ended up sending someone out that evening who fixed it within 15 minutes. We are so appreciated of the service- both the actual work done and the customer care. Highly recommend. Thank you to both Yiris!
Andre profile picture
Andre
02:52 19 Jun 25
Great service - fast, knowledgeable, thoughtful, very professional! Helped me well and fast!
HVAC Group responded quickly and had my noisy air conditioner fixed within a day. Their professionalism and customer-first approach really stood out. They go above and beyond—highly recommended!
Daniel Liu profile picture
Daniel Liu
19:04 04 Jun 25
HVAC group has been absolutely fantastic to help us replace our air conditioner. From diagnosing to replacement took only 2 days (since the replacement unit was in stock). This is especially appreciated as the weather was getting hot fast and I have a newborn baby that cries in the heat. Yura is extremely knowledgeable and Yuriy installed the unit professionally with no interruption and minimal noise to our house’s activities. Thank you for your help! HVAC group comes highly recommended and I’ll be reaching out to them for routine maintenance!
Pranav Kumar profile picture
Pranav Kumar
22:15 01 Jun 25
Got my thermostat changed and replaced the AC too. The price point is completely trust worthy and the service highly professional!
Olena M profile picture
Olena M
21:03 01 Apr 24
Amazing service, quick and clean replacement of the old water tank, we definitely recommend this team to anyone who would need installation or replacement
Daniel Campana profile picture
Daniel Campana
16:25 23 Mar 24
I had an issue with my Rheem furnace not heating, so I reached out to HVAC-group for assistance. The technician was quick to identify the problem as a faulty flame sensor. The service was prompt, efficient, and ultimately effective. I'm very pleased with their work and would highly recommend their services to anyone facing HVAC issues.
lakhbir phull profile picture
lakhbir phull
16:34 10 Mar 24
Excellent service, immediate response, reasonable price, very happy with their services.
Tina Obersnel profile picture
Tina Obersnel
12:18 29 Jan 24
I highly recommend calling HVAC-GROUP for your maintenance and service needs. Yuriy was great. Quick to respond and resolve the issue. I am very happy with the outcome.
VIKKY profile picture
VIKKY
19:29 17 Jan 24
I was having problem with a tankless water heater here in edmonton !
I just googled about it and i found his contact number , and i got my problem solved , because i called him and he actually explained everything very clearly and amazingly! Thank you so much
My tankless water heater was showing E110 , i was unable to get that, but he told me that you need clean the air intake filter then i open the panel and did exactly what he told me to do. By that why i got my problem solved!
Thanks buddy
Stan Ivanov profile picture
Stan Ivanov
15:37 20 Dec 23
I came from vacation to a broken furnace and a cold house. I called HVAC group late at night and they were able to send someone the next morning.

Technician was very professional, found that I had an igniter problem, had a spare part with him and solved the problem within an hour.

Reasonable pricing and very professional. Highly recommended!!!
Ingrid Turner profile picture
Ingrid Turner
07:26 13 Dec 23
Yuri is a true professional and is a very knowledgeable expert about furnaces.
I called him for advice when another well known Hvac company wrongly diagnosed my Trane furnace blower noise and told me I needed to undergo a $1500 repair. Yuri quickly assessed the problem and voila no more blower motor problems. All for $140!!
Thank you Yuri! I highly recommend your service, honesty and expertise.
Anisha Mathews profile picture
Anisha Mathews
18:19 29 Sep 23
Yuriy was very informative and helpful in selecting and installing our new furnace. His prices are very reasonable and the work was completed on time. He was also helpful in setting up our thermostat. I highly recommend his services!
Marah Di Nola profile picture
Marah Di Nola
21:36 14 Aug 23
Exceptional customer service, immediate response by phone & text, professional workmanship!! Clean respectful, very impressed with the workmanship. Thank you once again. Highly recommend for HVAC, water heater replacement. Answered all my queries without hesitation or reservation. Will definitely 💯 use again!!

Water Heater Experts

Comprehensive Tankless Water Heater Repair Services We Provide

Tankless Water Heater Diagnostics

Our technicians inspect heating elements, flow sensors, and gas valves to pinpoint issues. We check for ignition failures, clogged filters, and temperature inconsistencies to restore efficiency.

Error Code Troubleshooting

If your heater displays an error code, we identify and fix the issue. From E1 ignition failures to E5 overheating warnings, we reset sensors, clear blockages, and adjust system settings.

Burner & Ignition System Repair

A faulty burner, flame sensor, or thermocouple can prevent your system from heating water. We repair or replace components to ensure safe ignition and consistent heating.

Heat Exchanger Flushing & Descaling

Mineral buildup can reduce efficiency and cause overheating. We perform professional descaling to remove lime and calcium deposits to restore proper heat transfer and system performance.

HVAC Group technician installing a Navien tankless water heater for an energy-efficient and space-saving hot water solution

Flow Sensor & Water Pressure Adjustment

Low water pressure or temperature fluctuations? We clean or replace clogged flow sensors and adjust pressure regulators to ensure consistent hot water flow.

Gas Line & Exhaust Venting Inspection

We check for gas leaks, carbon monoxide buildup, and venting obstructions to ensure safe operation and proper airflow. All repairs follow HVAC safety codes.

Electrical System & Circuit Board Repair

If your unit won’t power on or cycles erratically, we inspect and repair damaged wiring, fuses, and circuit boards to restore functionality and prevent system failures.

Having a HVAC problem? We’ll FIX it today!

We’re available 24/7 to restore your comfort. Call now for same-day service!

Hot Water Anytime

Signs Your Tankless Water Heater Needs Repair – Don’t Ignore These Red Flags!

Sudden Loss of Hot Water

If your water heater stops producing hot water, it could be due to ignition failure, a faulty heating element, or gas valve issues. We diagnose and restore heating efficiency quickly.

Inconsistent Heating

Fluctuating temperatures may result from a clogged flow sensor, malfunctioning thermostat, or mineral buildup in the heat exchanger. Proper calibration ensures consistent hot water.

Rattling, Hissing, or Popping Noises

Unusual noises often indicate sediment buildup, air blockages, or burner malfunctions. A professional flush and burner inspection can resolve these issues and prevent long-term damage.

Fluctuating Water Pressure

Low or inconsistent water pressure can be caused by a clogged inlet filter, failing flow sensor, or plumbing obstructions. Adjustments and sensor repairs restore proper water flow.

Visible Leaks or Rust Buildup

Leaks around the unit or rust on pipes, fittings, or the heat exchanger may indicate corrosion, loose connections, or a failing pressure relief valve. Prompt repairs prevent major damage.

Strange Odours

A burning smell could signal electrical issues, while a sulphur-like odour may indicate gas leaks or bacteria in the water lines. Proper ventilation and system checks ensure safe operation.

Expert Maintenance for Every Water Heater Type

From Tankless to Traditional – Water Heater Types We Fix

Gas Tankless Water Heaters

We fix ignition failures, gas valve malfunctions, burner issues, and venting problems. Our technicians ensure safe gas pressure regulation and proper combustion for peak efficiency.

If your heating elements fail, circuit board malfunctions, or sensors misread temperature, we diagnose and repair electrical faults, thermostat failures, and wiring issues for consistent heating.

Condensing models require proper exhaust venting, condensate drain maintenance, and high-efficiency burner calibration. We fix corrosion issues, sensor errors, and heat exchanger buildup.

Qulaity Brands We Work With

From Carrier to Trane – The Best AC Brands We Work With

Heat Water Right

Who We Serve – Reliable Water Heater Repairs for Every Property Need

Residential

We repair tankless water heaters in homes, condos, and apartments, ensuring consistent hot water flow, efficient heating, and optimal water pressure. Our services include ignition system repairs, descaling, thermostat calibration, and leak detection to keep your home’s system running efficiently.

Commercial

Businesses require high-performance water heating for daily operations. We service restaurants, hotels, office buildings, and multi-unit properties, handling high-capacity flow rate adjustments, burner and gas valve repairs, exhaust venting issues, and emergency troubleshooting to minimize downtime.

High-efficiency tankless water heater installed by HVAC Group in Mississauga, ensuring reliable hot water supply

Stay Warm, Always

No Hot Water? Our Emergency Repair Service Is Just a Call Away!

A failing tankless water heater can disrupt your home or business. Our emergency repair service quickly resolves ignition failures, gas valve malfunctions, flow sensor issues, and error codes. We diagnose and fix low water pressure, overheating, and burner failures to restore hot water fast. Available 24/7 across the GTA for urgent repairs.

Emergency Water Heater Services

Get fast, same-day service with 24/7 availability for all your water heater emergencies. Whether it’s a sudden breakdown or no hot water, our expert technicians are ready to restore your comfort. Call now, and we’ll send help right to your door

HVAC Group technician performing maintenance on a tankless water heater to ensure efficient operation

Your Heating Experts

Save Energy & Money with Our Water Heater Services

A well-maintained water heater runs more efficiently, lowering energy bills and reducing wear on components. Our services include flushing, thermostat calibration, anode rod replacement, and burner optimization to prevent heat loss, improve recovery rates, and extend system lifespan.

Why to Work with Us

What Makes Us Stand Out? Here’s Why You Should Choose Us

Years of Experience

We have years of expertise in diagnosing and repairing tankless water heaters. Our team handles ignition issues, heat exchanger maintenance, and sensor calibration with precision.

Tailored Solutions

We customize flow rate settings, thermostat calibration, and burner adjustments to match your home’s hot water needs and energy efficiency goals.

Licensed & Experienced Technicians

Our certified technicians specialize in gas line repairs, circuit board troubleshooting, and burner adjustments. We ensure safe, code-compliant service for every repair.

Fast & Reliable Repairs

We offer same-day service for ignition failures, venting blockages, and pressure issues. Our team ensures minimal downtime and maximum system performance.

Advanced Tools & Techniques

We use gas leak detectors, thermal imaging, and multimeters to pinpoint error codes, heating failures, and electrical faults. Our methods ensure fast and accurate diagnostics.

Transparent Pricing

We provide upfront pricing with no hidden fees. Our estimates cover error code diagnostics, heat exchanger descaling, and system tune-ups with clear cost breakdowns.

High-Quality Workmanship

We follow manufacturer standards to deliver secure installations and durable repairs. Our work ensures optimal water heating and long-term system reliability.

Work With All Major Brands

We repair Rinnai, Navien, Noritz, Bosch, Rheem, Takagi, AO Smith, and Stiebel Eltron models. Our team uses OEM parts for reliable and lasting repairs.

Comfort Made Easy

Real Results from HVAC-Group Inc

Quality First HVAC Services Just A Call Away!

Business Hours
Monday to Friday: 8 a.m.–9 p.m.
Saturday and Sunday: 9 a.m.–2 p.m.

Location We Serve

HVAC-Group Inc. has been servicing Toronto and GTA surrounding areas for more than 20 year.

Summer's Calling! Get Our Exclusive AC Installation Deals

HVAC Group branded service van displaying heating and cooling repair services – Mobile HVAC service

Frequently Asked Questions

Can a tankless hot water heater be repaired?

Yes, most tankless water heater issues can be repaired. Common fixes include ignition system repairs, sensor replacements, burner cleaning, and heat exchanger descaling.

A well-maintained tankless water heater lasts 15–20 years. Regular descaling, filter cleaning, and component inspections help extend its lifespan.

Repairs depend on the issue. We diagnose error codes, flush scale buildup, adjust gas pressure, clean sensors, and repair electrical components to restore proper function.

Yes, they require regular maintenance and occasional repairs. Technicians can replace parts, clean filters, descale the heat exchanger, and troubleshoot system malfunctions

Yes, especially in areas with hard water. Flushing removes mineral buildup, prevents clogs, and maintains heating efficiency, extending the unit’s lifespan.

Yes! We provide professional tankless water heater installation for homes across Mississauga. Our technicians ensure proper sizing, setup, and performance so you can enjoy endless hot water with better energy efficiency and more space.

Labor costs vary based on the issue and brand. Basic repairs start at $150–$300, while complex fixes like heat exchanger replacement can exceed $500.

Common causes include ignition failure, a faulty flow sensor, clogged filters, or a gas supply issue. A professional diagnosis can pinpoint and resolve the problem.

Signs include fluctuating temperatures, error codes, unusual noises, low water pressure, and leaks. If you notice these issues, schedule a repair immediately.

Annual maintenance is recommended to keep your system running efficiently. This includes flushing the heat exchanger, cleaning filters, checking venting, and testing gas pressure

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