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Request ServiceWater Heater Repair — No Hot Water, Pilot Light & Emergency Service
Delex Plumbing diagnoses and repairs water heaters throughout Mississauga — no hot water calls, pilot light and thermocouple failure, anode rod replacement, pressure relief valve testing, and tank body leak assessment. Licensed, insured, flat-rate, same-day service.
No Hot Water — Diagnosing the Cause
Loss of hot water is one of the most disruptive plumbing failures a Mississauga household can experience. The cause of no hot water depends on whether the water heater is gas or electric, and whether the tank has no hot water at all or produces only lukewarm water. These two symptoms indicate different failure modes and require different repairs.
For natural gas water heaters — the most common type in Mississauga homes — no hot water at all typically indicates a pilot light outage, a failed thermocouple, or a faulty gas valve. Lukewarm water that runs out quickly indicates a thermostat set too low, a damaged dip tube directing cold inlet water directly to the hot outlet, or a tank that is undersized for the household demand. We identify which of these causes is responsible during the diagnostic visit before any parts are ordered or replaced.
For electric water heaters, no hot water indicates a failed heating element or a tripped high-temperature limit switch. Electric tanks have two elements — upper and lower — and both must function for full hot water recovery. A failed upper element means no hot water at all. A failed lower element means the tank produces a reduced volume of hot water. We test both elements with a multimeter and replace the failed element during the same visit.
Sediment accumulation at the tank bottom is a common cause of reduced hot water volume and efficiency in Mississauga. Peel Region water has high mineral content, and calcium carbonate sediment accumulates in the tank over time, reducing the effective tank volume and insulating the lower element or burner from the water. Annual tank flushing removes the sediment layer and restores full capacity.
Pilot Light, Thermocouple & Gas Valve Repair
A pilot light that will not stay lit almost always indicates a failed thermocouple. The thermocouple is a heat sensor positioned in the pilot flame — when the pilot flame heats the thermocouple tip, it generates a small electrical current that holds the gas valve open. A thermocouple that has oxidized, corroded, or physically failed generates insufficient current to hold the valve, and the pilot shuts off as a safety measure.
Thermocouple replacement is the most common water heater repair we perform. The procedure takes 30 to 45 minutes and restores normal water heater function immediately. We source OEM thermocouple assemblies for all major water heater brands — Bradford White, Rheem, AO Smith, Giant, GSW, and John Wood — and carry the most common replacement thermocouples on our service vehicles for same-visit repairs.
If thermocouple replacement does not restore pilot operation, the next component to check is the gas control valve. A faulty gas valve may prevent the pilot from lighting, prevent the burner from igniting when the thermostat calls for heat, or cause erratic operation. Gas valve replacement is more involved than thermocouple replacement and typically approaches the cost of a new water heater on older tanks. We advise honestly on whether a gas valve repair is economically justified based on the tank age and overall condition.
Gas supply pressure is also verified during every gas water heater service call. Insufficient gas supply pressure prevents the burner from producing the correct flame pattern and causes incomplete combustion. We confirm the gas valve inlet pressure is within the manufacturer specification and check the combustion air supply to the heater — an undersized or blocked combustion air opening causes the burner to operate with an oxygen-deficient flame. Power vent water heaters — common in newer Mississauga homes with sealed utility rooms — use a motor-driven blower to exhaust combustion gases through a horizontal PVC pipe rather than a vertical flue. Power vent motor failure is an additional failure mode not present in atmospheric units. The motor draws current that the control board monitors — a failed blower motor prevents the gas valve from opening as a safety interlock. We carry replacement blower motor assemblies for the most common Bradford White and Rheem power vent models.
Anode Rod Replacement & Tank Maintenance
The anode rod is a magnesium or aluminum rod suspended inside the water heater tank that sacrificially corrodes to protect the tank steel lining from electrolytic corrosion. In Mississauga hard water, anode rods deplete faster than in soft-water areas — typically in 3 to 5 years rather than the 5 to 7 year interval common in soft-water regions. A fully depleted anode rod leaves the tank steel exposed to electrolytic attack, causing pitting and eventual tank failure.
We include anode rod inspection in every water heater service call and recommend replacement when the rod is depleted to less than 50% of its original diameter. Anode rod replacement takes 30 to 45 minutes, extends tank life significantly, and is the single most cost-effective maintenance action for a water heater. Tanks with a depleted anode rod for multiple years may have already developed internal corrosion — we check for early tank failure signs during the inspection.
We also flush the tank sediment during the same visit as anode rod replacement. The flush removes the calcium carbonate layer from the tank bottom, improves energy efficiency, and extends element life on electric tanks. A tank that has not been flushed in over 5 years may require a slow drain to prevent sediment from blocking the drain valve — we manage this carefully to avoid valve damage.
Pressure Relief Valve & Tank Body Leak Assessment
The temperature and pressure (T&P) relief valve is a critical safety device on every water heater. It opens automatically if the tank pressure exceeds 1,034 kPa or the temperature exceeds 99 degrees Celsius. A T&P valve that is seeping, dripping, or has never been tested may be stuck in the closed position and unable to open when needed. We test the T&P valve during every water heater service call and replace it if it does not lift and reseat correctly.
A water heater tank that is leaking from the body — visible rust streaking or water pooling at the base — cannot be repaired and must be replaced. A pinhole in the tank lining will enlarge over time, and tank failure produces a sudden large volume of water in the utility room. We assess tank body condition during every service call and advise on replacement timing when the tank shows signs of impending failure.
If a water heater emergency is causing active flooding, call our emergency plumbing line at 416-910-2550 immediately. Close the cold water supply inlet valve on the water heater and turn the gas supply off at the valve on the gas line to the heater before we arrive. We will replace the unit on the same visit if the tank has failed. See our water heater installation page for replacement options. For scheduled water heater service — anode rod replacement, annual flush, thermocouple inspection — request service online and choose the next available appointment. We serve all Mississauga neighbourhoods including Port Credit, Clarkson, Erin Mills, Meadowvale, Cooksville, Malton, and Streetsville, with same-day and next-day availability most days of the week. All repairs are flat-rate with a written quote before any work begins.
Free Estimate — Call 416-910-2550
Every water heater repair starts with a free diagnostic estimate. Call 416-910-2550 or contact us online for same-day service across Mississauga.
Frequently Asked Questions
Q: How much does water heater repair cost in Mississauga?
A: Thermocouple replacement costs $180 to $320. T&P valve replacement costs $150 to $280. Anode rod replacement with tank flush costs $200 to $350. Electric heating element replacement costs $200 to $380. All prices are flat-rate. Call 416-910-2550 for a free diagnostic estimate.
Q: Why does my hot water run out faster than it used to?
A: Reduced hot water volume is most commonly caused by sediment accumulation at the tank bottom (reducing effective tank capacity), a failed lower heating element on electric tanks, or a broken dip tube directing cold water directly to the hot outlet. A tank flush and diagnostic visit restores full capacity in most cases.
Q: How do I know if my water heater needs to be repaired or replaced?
A: Repair is the right choice if the tank is under 10 years old and the failed component is a thermocouple, element, anode rod, or T&P valve. Replace if the tank is over 12 years old, has a leaking tank body, or has had multiple component failures in the past 2 years. We provide honest repair-vs-replace guidance during the diagnostic visit.
Q: Is it safe to relight my own pilot light?
A: Relighting a pilot light following the manufacturer instructions on the water heater label is generally safe if the pilot went out recently and there is no smell of gas. If you smell gas, do not attempt to relight — leave the building and call Enbridge Gas at 1-866-763-5427. If the pilot will not stay lit after 2 attempts, call 416-910-2550 for a thermocouple inspection.
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Or Give Us A Call: 416-910-2550
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