TANKLESS WATER HEATERS • NAVIEN SERVICE SPECIALIST • SERVICE • REPAIR • MAINTENANCE • INSTALLATION

Tankless water heater service, repair & installation in Toronto and the GTA.

DAVESDUCTS services, diagnoses, repairs, maintains, replaces and installs applicable tankless water heaters and combi systems. We are a Navien Service Specialist and can support the equipment through its lifecycle — from proper sizing and installation to fault-code diagnostics, repairs, flushing, preventative maintenance and eventual replacement.

SERVICE & REPAIR

No hot water, an error code or inconsistent temperature?

A tankless problem should be diagnosed before parts or replacement equipment are recommended. DAVESDUCTS services and repairs applicable tankless water heaters and combi systems, including Navien equipment.

No Hot Water

Diagnose applicable ignition, gas supply, water flow, controls and equipment faults when the appliance will not produce hot water.

Error Codes

Use the exact manufacturer fault code together with operating conditions and diagnostic testing to identify the underlying problem.

Inconsistent Temperature

Investigate applicable flow, scale, controls, recirculation and equipment conditions that may contribute to unstable hot-water delivery.

Leaks

Assess applicable internal or external water leakage and determine whether repair, component replacement or another corrective action is appropriate.

Venting / Condensate

Investigate applicable intake, exhaust, condensate drainage and related installation concerns.

Repair vs Replacement

Where repair remains practical, replacement may not be necessary. Equipment condition, diagnosis, parts availability and installation should guide the decision.

BEFORE THE SERVICE CALL

Send us the manufacturer, model number and exact error code.

Photos of the rating plate, appliance, piping and venting — plus a description of exactly what the unit is doing — can help us prepare for the diagnostic visit.

NAVIEN SERVICE SPECIALIST

Navien installation, diagnostics, repair and maintenance.

DAVESDUCTS is a Navien Service Specialist. Navien tankless water heaters, boilers and combi-boilers are an important part of our installation and service work.

Installation

Assess hot-water demand, gas capacity, venting, water piping, condensate, recirculation and mechanical-room conditions before selecting equipment.

Diagnostics & Repair

Diagnose no-hot-water complaints, fault codes, intermittent operation and performance concerns before recommending repair work or replacement parts.

Maintenance

Provide applicable flushing/descaling and preventative service together with inspection of equipment operation and related components.

WHY TANKLESS?

Hot water on demand without storing a full tank of heated water.

A tankless water heater heats domestic water as it is needed. It can reduce the floor space occupied by a conventional storage tank and avoids continually maintaining a large stored volume of hot water. The equipment still has to be sized for the home’s actual demand.

Continuous Production

A properly sized system can continue producing hot water while there is demand rather than being limited by a fixed storage volume.

Compact Equipment

Wall-mounted tankless equipment can free mechanical-room floor space compared with many conventional storage-water-heater installations.

Heat Water When Needed

Tankless equipment heats water in response to demand. Actual operating cost depends on equipment, usage, fuel rates and installation conditions.

PROPER SIZING

“Tankless” does not mean unlimited flow.

Every tankless water heater has finite heating capacity. Available hot-water flow depends on incoming-water temperature, desired outlet temperature and how much heat the appliance can transfer to the water.

Simultaneous Demand

Showers, tubs, faucets, dishwashers and other fixtures can overlap. Equipment should be selected around realistic simultaneous demand.

Temperature Rise

Colder incoming water requires more energy to reach the target outlet temperature and can reduce the flow a given appliance can support.

Large Hot-Water Loads

Large tubs or several simultaneous fixtures should be considered before equipment is selected. Some applications may require a different configuration or domestic-hot-water strategy.

INSTALLATION MATTERS

A tankless conversion is more than removing a tank and hanging a box on the wall.

Converting to tankless can affect gas piping, venting, condensate drainage, domestic-water piping, electrical supply, recirculation and the mechanical-room layout.

Gas Supply

Tankless equipment can create substantial gas demand. Existing gas piping, meter capacity and the building’s other connected gas loads should be reviewed.

Venting

Vent material, diameter, equivalent length, termination and combustion-air requirements must suit the exact appliance and approved installation.

Condensate

Condensing equipment produces condensate. Drain routing and applicable neutralization requirements should be addressed as part of the installation.

Water Piping

Piping and isolation/service valves should support required flow and allow future maintenance and flushing.

Electrical

Modern gas-fired tankless equipment requires electrical power for controls, ignition and other components.

Commissioning

The completed installation should be checked for applicable operation, combustion, venting, water delivery, drainage and controls.

HOT-WATER RECIRCULATION

Continuous hot water and fast hot-water delivery are not the same thing.

A tankless water heater can continuously heat water while there is demand, but cooled water already sitting in a long pipe still has to move before newly heated water reaches the fixture. An appropriately designed recirculation strategy can reduce that wait in suitable applications.

Dedicated Return

Where the home has a dedicated hot-water return line, compatible equipment and controls can circulate hot water according to the system design.

Retrofit Applications

Some equipment and approved piping arrangements can support retrofit recirculation strategies where a dedicated return is not available. The application should be reviewed before promising “instant” hot water.

WATER QUALITY & MAINTENANCE

Tankless water heaters still need preventative maintenance.

Mineral scale, inlet-filter debris, condensate issues and combustion-related conditions can affect operation. Maintenance requirements depend on the appliance, water quality, usage and manufacturer instructions.

Flushing / Descaling

Where required, the domestic-water heat exchanger can be flushed using an appropriate descaling procedure to address mineral accumulation.

More Than a Flush

Applicable service can include inspection of overall operation, filters, ignition/burner components, venting, condensate drainage, combustion performance and diagnostic history.

Ongoing Service

DAVESDUCTS can continue to maintain, diagnose and repair the equipment after installation.

CURRENT MAINTENANCE PRICING

Tankless flush + maintenance

$325 + HST for qualifying equipment originally supplied and installed by DAVESDUCTS.
$375 + HST for equipment installed by another contractor.

TANKLESS VS. COMBI

Domestic hot water only — or domestic hot water plus hydronic heating?

The terms are sometimes used interchangeably, but the applications are different.

Tankless Water Heater

Primarily intended to produce domestic hot water for showers, faucets, tubs and other domestic fixtures.

Combi Boiler

Designed to provide domestic hot water and serve an appropriate hydronic space-heating system from one appliance.

Explore Hydronics & Boilers →

REPLACEMENT

Replacing a tankless unit should include a review of the existing installation.

When an older appliance reaches the point where replacement makes sense, the new unit should not automatically inherit every detail of the old installation.

Existing Installation

Review gas piping, venting, condensate, water connections, electrical supply, clearances and serviceability.

Current Hot-Water Demand

Confirm whether the household’s fixture use or expectations have changed since the original equipment was selected.

Recirculation Strategy

Consider whether the replacement project is an opportunity to improve hot-water delivery to distant fixtures.

CURRENT EQUIPMENT

Select the model around the application.

Product families and specifications change. DAVESDUCTS selects current tankless equipment around hot-water demand, gas capacity, venting, recirculation requirements, installation conditions, serviceability and current manufacturer data rather than relying on an old model number.

NAVIEN

Current Navien tankless options

Navien offers multiple tankless configurations, including condensing and non-condensing product families and selected equipment with recirculation features. Exact models and specifications should be confirmed for the individual project.

CUSTOM HOMES & RENOVATIONS

Plan domestic hot water with the complete mechanical system.

For a custom home or major renovation, tankless equipment can be coordinated with gas distribution, hydronic heating, recirculation piping, mechanical-room design and the expected domestic hot-water loads before construction limits the options.

Gas Distribution

Coordinate tankless input with the home’s other gas-fired equipment and applicable meter/service requirements.

Recirculation Piping

Plan dedicated return piping during construction where the chosen domestic-hot-water strategy calls for it.

Mechanical Integration

Coordinate domestic hot water with hydronics and the rest of the mechanical system rather than designing each system in isolation.

Custom Home Mechanical Systems →

SERVICE REQUEST

What should you send us?

  • Project address / municipality
  • Manufacturer and model number
  • Clear photo of the rating plate
  • Exact error code if one is displayed
  • Photos of the appliance, visible piping and venting
  • Description of the problem and when it occurs
  • Whether the issue affects all fixtures or only certain fixtures
  • Whether there is visible water leakage or condensate leakage
  • For replacement/new installation: existing water-heater type and household hot-water requirements

TANKLESS WATER HEATER FAQ

Service, repair, maintenance and installation questions.

Does DAVESDUCTS repair tankless water heaters?

Yes. DAVESDUCTS diagnoses and repairs applicable tankless water heaters and combi systems, in addition to maintaining, replacing and installing them.

Is DAVESDUCTS a Navien Service Specialist?

Yes. DAVESDUCTS is a Navien Service Specialist and provides applicable Navien tankless water-heater, boiler and combi-boiler installation, diagnostics, repair and maintenance.

Can DAVESDUCTS service a tankless unit it did not install?

Yes, for applicable equipment within our service scope. Send the manufacturer, model, error code if present, photos and symptoms when requesting service.

How much is a tankless diagnostic service call?

The current starting residential diagnostic rate for a tankless water heater or combi boiler is $275 + HST. Repairs, replacement parts and additional labour are separate unless specifically included.

How much is tankless maintenance?

Current tankless flush and maintenance pricing is $325 + HST for qualifying equipment originally supplied and installed by DAVESDUCTS and $375 + HST for equipment installed by another contractor.

Does a tankless water heater provide unlimited hot water?

A properly sized unit can continue heating water while there is demand, but every appliance has a maximum heating capacity and flow rate. Simultaneous demand and required temperature rise still determine available hot-water flow.

Will tankless give me instant hot water?

Not necessarily. Water already sitting in the piping between the heater and fixture still has to move before newly heated water arrives. An appropriate recirculation strategy can reduce the wait in suitable applications.

Can I replace a conventional hot-water tank with tankless?

Often, yes, but gas capacity, venting, condensate drainage, domestic-water piping, electrical requirements, equipment location and hot-water demand should be assessed first.

How do you size a tankless water heater?

Sizing considers expected simultaneous hot-water flow and the required temperature rise from incoming water to the desired outlet temperature. Current manufacturer performance data should then be used to verify the selected equipment.

Does a tankless water heater need maintenance?

Yes. Preventative maintenance depends on the appliance, water quality, usage and system conditions and may include descaling plus inspection of filters, ignition, combustion, venting, condensate and overall operation.

What is the difference between a tankless water heater and a combi boiler?

A tankless water heater is primarily for domestic hot water. A combi boiler combines domestic-hot-water production with hydronic space heating in an appropriately designed system.

Should I repair or replace my tankless water heater?

That depends on the diagnosis, equipment condition, age, parts availability, installation quality and expected remaining service life. Diagnosis should come before assuming replacement is required.

NAVIEN SERVICE SPECIALIST • TORONTO & THE GTA

Need your tankless water heater serviced, repaired or replaced?

DAVESDUCTS can diagnose and repair your existing equipment, provide preventative maintenance, replace an aging appliance or design and install a properly sized new tankless system.

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