How often should a tankless water heater be serviced?
Regular servicing is what keeps a tankless water heater efficient and long-lived. But how often is often enough for a typical home?
For most Metro Vancouver and Fraser Valley households, once a year is the standard recommendation, with some homes benefiting from more frequent attention depending on water and usage.
Below, HeatLand explains the recommended service interval, what a proper service visit covers, and the signs that your unit may need attention sooner than scheduled.
The recommended service interval
For most homes, a tankless water heater should be professionally serviced once a year. This annual cadence is what manufacturers generally recommend to maintain warranty coverage and keep the unit performing efficiently. The main purpose is to remove scale from the heat exchanger before it disrupts heat transfer, along with cleaning the inlet filter and checking key components. Some households should service more frequently: harder water accelerates scale buildup, and heavy hot-water demand puts more work on the unit, both of which may warrant service every six to nine months. Metro Vancouver’s relatively soft water works in your favour, but annual service remains the baseline. Skipping service allows scale and sediment to accumulate, gradually reducing performance and shortening lifespan. Booking a consistent annual visit, ideally before the heavy winter heating season, is a simple way to protect your investment and avoid surprise breakdowns.
What an annual service includes
A thorough tankless service covers more than just descaling. A licensed technician typically flushes the heat exchanger with a descaling solution to remove mineral buildup, restoring efficient heat transfer and stable temperatures. They clean or replace the inlet water filter, which catches debris and can restrict flow when clogged. The burner and ignition system are inspected and cleaned to ensure clean, efficient combustion. Sensors and safety controls are checked for correct operation. The technician also examines venting for blockages or corrosion, verifies gas and water connections, and reviews any stored error codes. On a gas unit, confirming proper combustion and a clean blue flame is an important safety check. This combination of cleaning, inspection, and testing catches small problems early and keeps the unit running at its best. A documented annual service also supports warranty compliance and gives you a clear record of the unit’s condition.
Signs you need service sooner
Between scheduled visits, certain signs mean you should book service ahead of the annual date. Fluctuating or dropping water temperature, reduced hot-water flow, longer waits for hot water, or new noises like rumbling or clicking often indicate scale buildup or a clogged filter. Recurring error codes are a clear prompt for professional attention. Discoloured or foul-smelling hot water also warrants a check. If you have harder water or your household’s hot-water use has increased, do not wait a full year if performance drops. Safety note: some symptoms require immediate professional help rather than routine service. If you smell gas, notice soot or a yellow burner flame, suspect carbon monoxide, or find a leak from the unit body, shut it down safely and call a licensed, TSBC-certified technician right away. HeatLand offers maintenance plans and emergency service so your unit gets the right attention at the right time.
Quick Checklist
- Book professional service about once a year
- Service more often with harder water or heavy use
- Schedule before the winter heating season
- Watch for reduced flow, swings, or new noises between visits
- Address recurring error codes promptly
- Call immediately for gas smell, soot, or leaks
| Household Condition | Suggested Service Frequency |
|---|---|
| Typical home, soft water | Once a year |
| Harder water | Every 6-9 months |
| Heavy hot-water demand | Every 6-9 months |
| Performance drop noticed | As soon as possible |
Frequently Asked Questions
Is annual service really necessary for a tankless heater?
Yes. Annual service removes scale before it disrupts performance, cleans the filter, and checks combustion and safety controls. It also often supports warranty coverage. Skipping it lets scale and sediment accumulate, reducing efficiency and shortening lifespan. Once a year is the baseline for most homes, with harder water or heavy use warranting more.
Can I service a tankless water heater myself?
Some owners handle basic filter cleaning, but full service, including descaling on a gas unit and combustion checks, is best done by a licensed technician. Gas, venting, and combustion work requires TSBC certification. If you smell gas or notice combustion problems, do not attempt anything yourself; call a professional immediately.
Does soft water mean I can skip yearly service?
No. Metro Vancouver’s soft water slows scale buildup, which helps, but scale still forms over time. Annual service also covers filter cleaning, combustion, venting, and safety checks that are unrelated to water hardness. Keep the yearly schedule even with soft water to protect performance and lifespan.
When is the best time of year to service my unit?
Scheduling service before the winter heating season is ideal, since cold Metro Vancouver mains water makes the unit work harder in winter. Servicing beforehand ensures the heat exchanger is clean and the unit is ready for peak demand, reducing the chance of a mid-winter breakdown when you need hot water most.
Reviewed by the HeatLand Heating & Cooling team — licensed HVAC contractor serving Metro Vancouver & the Fraser Valley since 1999. This article is for general guidance only. If you smell gas, suspect a carbon monoxide leak, or are unsure about any electrical or gas component, stop troubleshooting immediately and call a licensed technician or 911.