A. O. Smith is one of the largest water heater manufacturers in North America, and its Canadian business is run from Fergus, Ontario, the home of GSW, the manufacturer it acquired in 2006. Manufacturing in Fergus ended in 2013; the head office, warranty desk and technical support stayed. John Wood and GSW are its sister brands in Canada, and Takagi tankless heaters and Lochinvar boilers belong to the same group.
Find your tank type first. A metal vent rising to a chimney with no power cord is atmospheric gas, and a blower on top with plastic pipe through the wall is power vent. No vent at all and a 240-volt cable is electric. A tall unit with a fan and a compressor housing on top is a hybrid heat pump.
The local factor is water. Halton and Hamilton draw hard water from Lake Ontario, and rural properties in Caledon and Flamborough on private wells often have harder water still. Sediment and anode wear are the ordinary way an A. O. Smith tank ages here, whatever its fuel.
ZK Mechanical is an independent, owner-operated contractor and services A. O. Smith without a brand tie. If the tank carries a rental sticker, the rental company owns it and repairs it; call them first. Everything below applies to a tank you own.
A. O. Smith lines we install and service
The standard chimney-vented gas tank. Combustion air enters through a screened intake at the base and the gas control at the front reports faults with a status light. No power supply is needed, so it keeps heating through a hydro outage.
Gas tanks with a blower that exhausts through plastic pipe in the side wall; power direct vent models add a second pipe for outdoor combustion air. An electronic control proves airflow with a pressure switch before lighting the burner.
Condensing gas water heaters for large households or combined space and water heating. They produce condensate that must drain freely, and they are serviced more like a condensing furnace than like a basic tank.
Two-element electric tanks with an upper and a lower thermostat. They are simple, quiet and cheap to repair. Hard water scales the elements, and the lower one sits in the sediment and fails first.
An electric tank with a heat pump on top that pulls heat from the surrounding air, with standard elements as backup. It needs air space around it, a condensate drain and a clean air filter. See heat pump water heaters for whether your mechanical room suits one.
What goes wrong on A. O. Smith equipment
Gas control status light is flashing a fault
The status light on the gas control valve reports three faults we see regularly: low thermopile voltage, which means a weak pilot signal; a temperature-sensor fault; and a high-temperature shut-off. The first is often a thermopile or a dirty pilot. The other two usually mean the control is replaced, at $400–$600. Flash counts differ between control makes, so read the legend on the tank and see what the blinking light on a water heater means.
Power vent or power direct vent will not fire
The blower runs and the burner stays off, or nothing happens at all. The causes are a failed blower, a failed pressure switch or a blocked intake or exhaust pipe. On a power direct vent tank both pipes end outside, and either one can ice over or fill with snow against a wall where it drifts. Clear both terminations before you call; blower and switch repairs fall within the $150–$800 band.
Anode depletion and sediment in hard-water areas
The anode rod corrodes so the tank does not, and on hard water it can be down to bare wire within a few years. After that the steel is unprotected. Sediment builds on the floor of the tank and causes rumbling, slow recovery and, on gas tanks, an overheated tank bottom. Flushing the tank and checking the anode at a maintenance visit costs far less than the leak that follows a spent anode.
Electric and hybrid: no hot water or a high hydro bill
On an electric tank, lukewarm water means a failed lower element, $200–$400 to replace. On a Voltex hybrid, a clogged air filter or a blocked condensate drain stops the heat pump, and the tank falls back to its elements. You still have hot water, and the electricity bill climbs. Our heat pump water heater repair page covers the refrigerant-side faults.
A. O. Smith warranty: what to know
- Warranty terms vary by model and are printed on the tank's label and warranty sheet, with separate terms for the tank and for component parts.
- In Canada, warranty validation and technical support are handled by A. O. Smith Enterprises in Fergus, Ontario. Have the model and serial number from the rating label ready before you call.
- The warranty supplies a tank or a part. It does not cover labour, any permit, disposal of the old tank or damage from a leak.
- Keep the installation invoice as proof of the install date and of installation by a licensed gas technician. A gas water heater installed without one is a problem for a claim and for your insurer.
Parts availability in the GTA
A. O. Smith parts are well supplied in the GTA and Hamilton, helped by the shared platform with John Wood and GSW. Thermopiles, gas control valves, elements, thermostats, anode rods, relief valves and drain valves are counter stock at plumbing wholesalers, while power-vent blowers, pressure switches and electronic controls are matched to the model and ordered by the numbers on the rating label. Vertex and Polaris components and Voltex heat pump parts are more specialized and can take longer, so we check availability before quoting. On a tank past 10 years we price the replacement beside the repair, because an expensive part on an old tank is rarely the better buy.
A. O. Smith Water Heater Error Codes Explained — what each one means and whether it is safe to keep running.
Common questions
Are A. O. Smith water heaters made in Canada?
Not in Fergus any more. A. O. Smith bought GSW and its Fergus, Ontario plant in 2006 and ended manufacturing there in 2013. The Canadian head office, warranty desk and technical support remain in Fergus, and tanks sold here under the A. O. Smith, John Wood and GSW names are built at the company's other plants.
Should I repair or replace my A. O. Smith tank?
Repair it when the tank is under 8 years old and the fault is a part: a thermopile, gas control, element, blower or valve. Replace it when water is coming from the tank body, or when the tank is past 10 to 12 years and the repair is a major part. Our water heater repair versus replacement analysis works through the costs.
Is an A. O. Smith hybrid heat pump water heater worth it?
For a household heating water with electricity, usually yes: a hybrid uses far less power than a standard electric tank. It needs a room with enough air volume, a drain for condensate and tolerance for some fan noise. It costs more to buy than a plain tank. Check the current heat pump water heater rebate page before deciding, because programs change.
Do you service Takagi tankless heaters too?
Yes. Takagi belongs to the same group as A. O. Smith, and its tankless units are serviced like other gas tankless heaters: descaling, inlet filter cleaning, and flame rod and fan checks. On local hard water an annual descale flush is $150–$300. See tankless water heater repair for the common faults.
What temperature should my A. O. Smith water heater be set to?
Store the water at 60°C, which controls Legionella bacteria in the tank. Delivery to the taps should be limited to 49°C to prevent scalding. A thermostatic mixing valve at the tank gives you both. Turning the dial down instead leaves the tank lukewarm, and that is the range bacteria prefer.