Home Services Maintenance About Contact Call (437) 999-4242

Tankless Water Heater Repair in Mississauga

Expert tankless water heater diagnostics and repair. We fix error codes, descale units, replace parts, and restore your endless hot water.

What's Included

Error Code Diagnosis

Full diagnostic of error codes to identify the exact issue with your tankless unit.

Descaling

Thorough descaling to remove mineral buildup and restore optimal heat transfer efficiency.

Igniter / Flame Sensor Repair

Inspection and replacement of igniter and flame sensor components for reliable ignition.

Flow Sensor Check

Flow sensor testing and calibration to ensure proper water detection and activation.

Why Choose Olu HVAC Mississauga

Mississauga homeowners trust us for thorough, honest tankless water heater repair that restores reliable hot water on demand.

Mississauga Based

Olu HVAC Mississauga is based at 7433 Sigsbee Dr in Mississauga and works across the GTA.

Open 24 Hours

Call (437) 999-4242 any time. We answer outside business hours.

Upfront Pricing

No surprises or hidden fees. We quote a flat rate before starting any work so you always know the cost.

Tankless Water Heater Acting Up?

Call us today for expert tankless water heater repair in Mississauga.

Call (437) 999-4242

Service Details

Tankless Water Heater Repair: what matters before you book

Tankless repair depends on the error code, water flow, ignition, venting, maintenance history, and water quality. A service visit should separate a simple maintenance issue from a failed component.

Error codes

Codes help narrow the problem but still need on-site confirmation.

No hot water

Flow sensor, ignition, gas, venting, or control issues can stop operation.

Temperature swings

Scaling, flow rate, mixing valves, or demand changes can affect outlet temperature.

Maintenance history

Units that have not been flushed may need descaling before parts are replaced.

Inspection Focus

What OLU HVAC checks on the visit

  • Displayed error code and operating history.
  • Water flow, filter screen, and scale indicators.
  • Gas supply, ignition, venting, and condensate path.
  • Isolation valves and flushing access.
  • Repair cost compared with unit age and condition.

Process

How the service call moves forward

Confirm the request

We start with the symptoms, equipment type, location, access notes, and how urgent the issue is.

Inspect the system

The technician checks the parts of the system that can actually cause the problem before quoting work.

Review the next step

You get a practical repair, maintenance, or replacement recommendation before approved work begins.

FAQ

Common Questions

Real answers to questions Mississauga and GTA customers ask us most.

My tankless unit is showing an error code. What does it mean?

+

Error codes vary by brand. Common causes are scaling, ignition issues, low gas pressure, or venting blockages. We diagnose the actual cause and fix it.

How often should a tankless water heater be flushed?

+

Once a year in Mississauga's typical water hardness, more often if you have very hard water. Annual flushing prevents scale build-up that causes errors and shortens life.

Why is my hot water sometimes cold then hot?

+

Often caused by a scaling-induced ignition delay, a flow-rate issue, or sensor problems. We diagnose the actual cause.

Do you offer emergency tankless service?

+

Yes. Call (437) 999-4242 for 24-hour service.

Book Your Service

Olu HVAC Mississauga is open 24 hours. Call us, email us, or send a message.

Call (437) 999-4242 Contact Us
Call Us