Tankless Water Heater Repair in Calgary

Manufacturers generally quote around 20 years, roughly double a tank, and that figure assumes annual descaling. On Calgary water without maintenance, we see them fail considerably earlier — the heat exchanger is the life-limiting part and scale is what ends it.

The useful way to think about it: a tankless unit's lifespan is decided by water treatment and servicing far more than by the badge on the front. A serviced unit on softened water will outlast a neglected one by years.

Usually one of two things. The unit may be short-cycling because the flow rate has dropped below what it needs to stay firing — a water-saving showerhead, a partly closed valve, or a clogged inlet filter will all do it. Or the heat exchanger is scaled enough that it cannot hold its output under steady demand.

There is also a harmless version: older units have a brief lag between the tap opening and full output, sometimes called a cold water sandwich, which is characteristic of the technology rather than a fault. If it is happening repeatedly within one shower, that is not it.

If it was installed with isolation valves, yes — you need a small pump, a bucket, descaling solution and a couple of hoses, and plenty of homeowners manage it.

What the DIY version misses is the rest of the service: combustion check, gas pressure under full fire, condensate trap, inlet filter and vent terminals. Those are where we find the faults that would otherwise strand you in January. If you are doing it yourself, at minimum clean the inlet filter at the same time and look at the vent outside.

It can affect it. Most manufacturers require documented annual maintenance for the heat exchanger warranty to hold, and several specifically address water hardness in their terms.

We would not tell you what your particular warranty says — check the paperwork for your brand and model year, because terms differ. What is consistent is that documented annual servicing protects the coverage, and on Calgary water it is worth having regardless of what the warranty demands.

Once, reasonably. A single fault after a gas interruption or a power blip can be genuine.

A code that comes back is information, not noise — particularly the overheat codes (Rinnai 14, Navien E016), which generally mean heat is not transferring into the water because of scale. Repeatedly resetting an overheat condition is running the unit in the state its safety shutdown exists to prevent. Ignition and combustion codes likewise need someone with a manometer rather than another reset.

Because it is doing a harder job. A tankless heater raises incoming water by a set number of degrees at a given flow rate, and Calgary's inlet water is far colder in January than in July. Same unit, same setting, much more work.

If yours delivers two simultaneous showers in summer and one in winter, that is usually capacity rather than a fault — it was sized against a warmer inlet than we actually get here. A descale may recover some margin if it has never been done, but a genuinely undersized unit cannot be repaired into being bigger.

Same-day across Calgary and Airdrie wherever the schedule allows, and we will tell you honestly when the realistic window is rather than promising an hour we cannot hold. Call 587-834-3668.

If the unit is leaking rather than simply not heating, shut off the water supply to it and the gas, and call — that one does not wait.

It depends on what failed rather than how old it is. Components — flow sensor, flame rod, igniter, fan, board — are generally worth repairing on a sound unit. A failed heat exchanger out of warranty often costs most of a new heater, and at that point replacement is the better value.

We quote both when it is close, in writing, and we would rather tell you a repair is not worth doing than take the money for one that buys you a season.