Fast & Reliable Tankless Water Heater Repair
Get your hot water back — same-day service, certified technicians, and expert repairs for all major tankless brands. Serving Toronto, the GTA & beyond with 24/7 emergency support.
Tankless Water Heater Repair and Service in Canada
Tankless water heaters are renowned for their energy efficiency and on-demand hot water, but like any appliance, they require professional care to maintain optimal performance. Whether you own a Navien, Rinnai, Bosch, or Rheem unit, our certified technicians have the expertise to diagnose and repair issues promptly, no matter the brand or model.
With Canada’s cold winters and rising energy costs, it’s essential to keep your tankless system in peak condition. At City Energy, we offer 24/7 emergency repair services, preventive maintenance plans, and genuine replacement parts to restore your comfort quickly and safely.
Don’t wait for a total breakdown. Contact City Energy for expert tankless water heater service near you, because your home deserves consistent hot water and dependable performance year-round.
Common Tankless Water Heater Problems
While tankless water heaters are praised for their energy efficiency and convenience, they aren’t immune to occasional issues, especially in Canada’s demanding climate. At City Energy, we’ve seen it all. Here are the most common problems our certified technicians encounter and fix across Toronto, the GTA, and surrounding regions:
No Hot Water
One of the most frequent complaints is turning on the tap only to find no hot water. This can be caused by a range of issues, from a faulty flow sensor to a tripped circuit breaker or even a frozen pipe in winter. If your system isn’t igniting or heating properly, it’s time for a professional diagnosis.
Inconsistent Water Temperature
Does your water swing between hot and cold? Temperature fluctuation often points to a clogged filter, mineral buildup in the heat exchanger, or a malfunctioning thermostat. Our team can quickly identify the cause and restore stable, reliable heat.
Error Codes on Display Panel
Modern tankless units are smart — they show error codes when something goes wrong. Whether it’s a code for ignition failure (like Error 11 on Rinnai units) or a venting issue, our experts can interpret these alerts and resolve the underlying problem with precision.
Low Water Pressure or Flow Rate
If your tankless system isn’t delivering adequate flow, it could be due to sediment buildup, a clogged inlet screen, or improper sizing of the unit for your home’s needs. We’ll inspect your unit and plumbing to ensure peak performance.
Mineral Buildup and Hard Water Scaling
Canadian water, especially in areas like Southern Ontario, is often hard, full of calcium and magnesium. Over time, this leads to limescale deposits in your tankless water heater, reducing efficiency and shortening its lifespan. Descaling is essential maintenance to prevent this issue.
Strange Noises (Clicking, Rumbling, or Hissing)
Unusual sounds can signal blockages, loose components, or gas flow issues. Don’t ignore these signs — what starts as a minor rattle can escalate into major damage without professional attention.
Frozen Pipes in Winter
In colder provinces, unprotected exterior or garage installations may lead to frozen water lines, which can trigger system errors or even damage internal components. We offer weatherproofing solutions and emergency winter repairs to keep your unit running reliably.
Signs Your Tankless Water Heater Needs Repair
Tankless water heaters are designed for longevity and efficiency, but even the best systems can show signs of wear and tear over time. Knowing when to call for professional tankless water heater repair can help you avoid unexpected breakdowns, water damage, and costly replacements. If you notice any of the following issues in your home or business, it’s time to call the experts at City Energy.
Inconsistent or No Hot Water
If your shower suddenly runs cold or your faucets take forever to heat up, your tankless water heater may be struggling with flow sensor failures, clogged filters, or heating element malfunctions. Don’t ignore this — inconsistent hot water is one of the clearest indicators that your system needs servicing.
Fluctuating Water Temperature
Experiencing temperature swings while washing your hands or taking a shower? This could signal mineral buildup, blockages, or a failing thermostat. It’s not just annoying, it’s a sign of a deeper problem that could affect energy efficiency and system safety.
Water Leaks Around the Unit
If you see water pooling beneath your tankless water heater, you may be dealing with a cracked heat exchanger, faulty valves, or loose connections. Leaks not only damage the unit but can also lead to mold, mildew, or structural damage in your home.
Error Messages or Flashing Warning Lights
If your unit displays error codes or blinking lights, it’s not something to ignore. These alerts could indicate anything from venting problems to gas line issues. City Energy’s certified technicians can diagnose and resolve these warnings to prevent further damage.
Unusual Noises from the Unit
Clicking, hissing, rumbling, or banging noises coming from your tankless water heater often suggest debris buildup, air in the gas line, or loose components. Any strange sound should be taken as a warning to schedule a repair visit right away.
Low Water Pressure
A noticeable drop in hot water pressure often points to scaling inside the pipes, sediment buildup, or internal flow sensor issues. These problems are especially common in regions with hard water, such as parts of Ontario.
Spike in Utility Bills
If your gas or electricity bills suddenly increase with no obvious explanation, your tankless system might be working overtime due to inefficiency or internal blockages. A quick service check can help restore its performance and save you money.
Our Expert Tankless Water Heater Repair Services
At City Energy, we specialize in comprehensive tankless water heater repair services designed to restore hot water fast and efficiently. Whether you’re dealing with a minor issue or a complete system failure, our team of licensed HVAC professionals delivers expert diagnostics, fast fixes, and long-lasting solutions you can count on.
What Our Tankless Water Heater Repair Services Include:
- Ignition and Burner Repair:
If your unit isn’t producing hot water due to ignition failure or burner malfunction, we’ll repair or replace the necessary components to get your hot water running again, safely and efficiently.
- Error Code Troubleshooting:
Tankless water heaters often display error codes (e.g., Error 11, 29, or 61). Our technicians are trained to decode these messages and fix underlying issues such as blocked vents, faulty sensors, or gas flow problems.
- Descaling and Mineral Buildup Removal:
Hard water is a common issue in many parts of Canada. We provide professional descaling services to remove limescale and improve the efficiency and longevity of your unit.
- Water Flow & Pressure Restoration:
If you’re experiencing reduced flow rates or water pressure, we’ll inspect filters, flush the system, and check for internal clogs or pipe issues to restore full functionality.
- Component Replacement:
From heat exchangers and temperature sensors to flow valves and circuit boards, we replace worn or faulty parts using OEM-grade components for reliable performance.
- Emergency Repair Services (24/7):
No hot water in the middle of winter? We offer 24/7 emergency tankless water heater repair across the Greater Toronto Area, so you’re never left out in the cold.
Preventive Maintenance for Tankless Water Heaters
Preventive maintenance is the key to maximizing the lifespan, efficiency, and reliability of your tankless water heater, especially in Canada’s cold, mineral-rich environments. City Energy offers expert tankless water heater maintenance services designed to keep your system operating efficiently year-round, helping you prevent unexpected breakdowns and expensive repair costs.
Why Preventive Maintenance Matters
Tankless water heaters operate differently from traditional tanks as they heat water on demand, which means they’re always “on call.” Over time, internal components can become clogged with limescale, sensors may degrade, and filters can become obstructed, especially in regions with hard water, like Southern Ontario.
Neglecting regular servicing can lead to:
- Decreased energy efficiency
- Inconsistent water temperature
- Frequent error codes or system shutdowns
- Premature part failure or total system breakdown
- Voided manufacturer warranties
What Our Tankless Water Heater Maintenance Service Includes
City Energy’s annual maintenance service is thorough, professional, and tailored to your model and water conditions. Our preventive maintenance checklist includes:
- Full system inspection
- Flushing and descaling the heat exchanger to remove mineral buildup
- Cleaning or replacing water and air filters
- Inspecting venting and exhaust systems
- Checking for leaks, corrosion, or gas line issues
- Verifying ignition performance and combustion safety
- Testing temperature control and water flow rate
- Reviewing diagnostic history and clearing error codes
Recommended Maintenance Frequency
- Once per year is ideal for most homeowners
- Every 6 months, if you live in a hard water area or have high household usage
- After winter to inspect for any freeze-related wear or damage
We also offer maintenance plans that include scheduled visits, priority service, and exclusive discounts on repairs and replacements.
We offer 24/7 Emergency Service to all our customers.
Why Choose City Energy for Tankless Heater Repair
Certified HVAC Technicians with Specialized Expertise
At City Energy, every technician is fully certified, insured, and trained specifically in tankless water heater systems, including major brands like Navien, Rinnai, Bosch, and Noritz. We don’t just offer general plumbing or HVAC service; we bring targeted expertise that ensures your tankless system is diagnosed and repaired correctly the first time. Our team stays up to date on the latest models, technologies, and safety protocols. This specialized knowledge allows us to provide fast, accurate service, even on complex issues such as ignition failure, venting problems, or scale buildup. With City Energy, you’re getting professional-level service that protects your investment and restores comfort efficiently, no guesswork, no delays, just expert care every time.
Fast Response Times Across the GTA
We know that hot water interruptions can quickly become stressful, especially during Canada’s freezing winters. That’s why City Energy is proud to offer rapid-response repair services throughout Toronto, Mississauga, Vaughan, Markham, Richmond Hill, and the entire GTA. Our local dispatch teams are strategically positioned to minimize wait times and maximize service efficiency. Whether you need same-day service or a late-night emergency fix, our mobile units are stocked and ready to go. We respond to your calls promptly, show up on time, and resolve problems quickly so you can get back to your daily routine. City Energy is built for speed and reliability, because no one should wait days for hot water in the middle of winter.
Transparent Pricing & Honest Service
At City Energy, we believe in clear communication and upfront pricing — no hidden fees, surprise charges, or inflated costs. Before we begin any repair, we provide a detailed quote and breakdown so you know exactly what to expect. Our reputation is built on integrity, fairness, and professionalism, and we’ll never upsell unnecessary services or parts. Whether you’re dealing with a minor clog or a major component failure, we give you honest recommendations based on what’s best for your comfort and budget. We’re proud to be a locally trusted HVAC company in the GTA, and we treat every home like it’s our own. When you choose City Energy, you’re choosing transparent, dependable service you can trust.
Deep Experience with Gas & Electric Tankless Systems
City Energy has years of hands-on experience servicing both gas and electric tankless water heater systems, making us a one-stop solution for all homeowners and businesses. Whether your home runs on natural gas, propane, or electric models, our team has the skills, tools, and knowledge to fix your unit with precision. Gas-powered units often involve venting, ignition, and combustion concerns, while electric models may have circuit board or heating element issues — we’re trained to handle both. We also understand the different demands of residential vs. commercial tankless systems and tailor our repair approach accordingly. Our versatility and broad expertise set us apart, ensuring you receive high-quality repairs, regardless of your system type.
Don’t Wait — Schedule Service Before It Becomes an Emergency
City Energy’s expert HVAC technicians are trained to spot issues early and provide cost-effective, long-lasting repairs for all major brands of tankless water heaters across Toronto, the GTA, and Southern Ontario. Get in touch today to book a diagnostic visit or request emergency service.
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Frequently Asked Questions
What are the signs that my tankless water heater requires servicing?
If you’re experiencing fluctuating water temperature, low water pressure, no hot water, or seeing error codes on your display, it’s a clear sign your unit needs servicing. Other indicators include strange noises, leaking water, or a sudden spike in utility bills. If any of these symptoms appear, contact City Energy for a professional inspection.
Can I repair a tankless water heater myself?
While basic troubleshooting, like resetting the unit or cleaning filters, is safe, tankless systems are complex. Most repairs, especially those involving gas lines, heating elements, or electrical components, should only be handled by certified technicians. DIY repairs may also void your warranty or create safety risks. Trust City Energy’s licensed experts for safe, effective solutions.
Is it better to repair or replace a tankless water heater?
If your unit is less than 10 years old and the repair is minor, fixing it is often the most cost-effective choice. However, if your unit is over 15 years old, out of warranty, or has recurring issues, replacement may be the better investment. Our technicians will assess the condition and offer honest guidance based on your needs.
How often should I service a tankless water heater?
For most homes, annual maintenance is recommended to flush out mineral buildup, clean filters, and inspect internal components. Homes with hard water or heavy usage may require service every 6–9 months. Regular maintenance helps extend the lifespan of your unit, maintain efficiency, and avoid expensive breakdowns.
Do tankless water heaters work well in cold Canadian climates?
Yes, modern tankless water heaters are engineered to operate efficiently in cold Canadian winters. However, proper installation, insulated pipes, and regular maintenance are crucial to prevent freezing and performance loss. City Energy’s technicians ensure your unit is winter-ready and optimized for Canada’s climate.