Descale your washing machine monthly by adding 100g of citric acid powder directly to an empty drum and running the hottest, longest cycle available, followed by a plain rinse cycle. In Toronto and the GTA, moderately hard tap water deposits limescale on heating elements, drum walls, and internal hoses — reducing efficiency, stiffening clothes, and shortening the appliance's lifespan. Descaling takes under two hours with no hands-on effort.
Quick Summary
- Best descaler: Citric acid (100g in drum) — more effective than vinegar for calcium deposits
- Frequency: Monthly in Toronto/GTA (hard water area)
- Cycle: Hottest setting, empty drum, no detergent — then one rinse cycle
- Signs you need it: Stiff clothes, white film on darks, musty smell, longer cycles
- Front-load: Use drum clean cycle if available; wipe gasket after
Why Toronto Homeowners Need to Descale More Often
Toronto's municipal tap water has a hardness of approximately 124–150 mg/L — classified as moderately hard. Over a month of regular washing, this translates to a meaningful layer of calcium carbonate (limescale) coating the inside of the drum, the heating element, and the water inlet valve.
The heating element is the most vulnerable component. It operates at high temperature, which accelerates scale crystallisation on its surface. A thick layer of limescale acts as an insulator — the element must work harder and run longer to heat the same amount of water. Over time, this causes the element to overheat and fail. Heating element replacement is one of the most common washing machine repairs in the GTA — and most cases are directly attributable to hard water scale.
What You Will Need
- Citric acid powder — available at bulk food stores, pharmacies, and hardware stores for $3–$6 per 250g. 100g per descaling cycle.
- OR a commercial washing machine descaler — Calgon, Oust Washing Machine Descaler, or Affresh. Follow product instructions.
- Microfibre cloth for wiping the drum and gasket after the cycle
Step-by-Step: How to Descale a Washing Machine
Start with an empty drum
Remove all laundry and any items left inside. Check the drum for forgotten socks or small items. Descaling must be done on an empty machine — clothing interferes with the process and concentrated acid can damage fabric.
Add citric acid directly to the drum
Dissolve 100g (about 6 tablespoons) of citric acid powder in a cup of warm water, then pour it directly into the drum — not the detergent dispenser. The dispenser will dilute and flush out the acid before it can work on the drum and internal components. Do not add any detergent, fabric softener, or other products.
Select the hottest long cycle
Choose the hottest wash temperature available — 60°C minimum, 90°C if your machine offers it. Select the largest or heaviest load setting to ensure maximum water volume. Many front-loaders have a dedicated Drum Clean or Tub Clean cycle — use this if available, as it is optimised for internal cleaning.
Run the full cycle
Allow the cycle to run completely without opening the machine or interrupting it. The heated citric acid solution circulates through the entire water path — drum, pump, hoses, heating element, and water inlet. The acid dissolves calcium and magnesium carbonate deposits that water alone cannot shift.
Run a plain rinse cycle
Select a rinse and spin cycle with no products added. This flushes residual citric acid from the system so it does not contact your next laundry load. The acid is food-safe, but concentrated residue on fabrics can affect some dyes.
Wipe the drum and door seal
Open the machine and wipe the interior drum with a damp cloth — you may see dislodged white scale particles that have settled on the drum floor. On front-loaders, pull back the rubber door gasket and wipe inside the folds where scale and mould accumulate together. Leave the door open for 1 hour to air-dry.
Front-Load vs Top-Load: Descaling Differences
Front-Load Washers
- Use the Drum Clean / Tub Clean cycle if available
- Lower water usage concentrates minerals — more prone to scale
- Wipe the door gasket after descaling — scale weakens rubber
- Check and clean the pump filter monthly as scale deposits can accumulate there
Top-Load Washers
- No dedicated drum clean cycle on most models — use hottest, largest cycle
- Can pause cycle after drum fills for a 30-minute soak — increases descaler contact time
- Wipe under the drum rim and around the agitator base after the cycle
- Check the fabric softener dispenser cup — scale builds up there too
Prevention tip: Add a water softening detergent additive (Calgon Washing Machine Water Softener) to every load if you do high-volume laundry. This is the most effective way to prevent scale from forming on the heating element between descaling cycles.
Do not mix descalers. Never add citric acid and bleach in the same cycle — this produces toxic chlorine gas. If you recently ran a bleach cycle, run a plain rinse cycle first before descaling with citric acid.
Frequently Asked Questions
Descale monthly if you live in a hard water area like Toronto or the GTA. Toronto tap water hardness is around 124–150 mg/L (moderately hard), which causes noticeable scale buildup over 4–8 weeks of regular use. If your clothes feel stiff or you see white film on dark items, increase descaling frequency to every 2 to 3 weeks.
Yes, citric acid is safe for most washing machines when used correctly — in the drum on a hot cycle, rinsed afterward. It is gentler than vinegar on rubber seals and more effective than white vinegar at dissolving calcium deposits. Avoid using it too frequently (more than twice a month) as repeated acid exposure can eventually affect seals.
White vinegar works as a mild descaler and deodoriser, but citric acid is approximately three times more effective at dissolving limescale at the same concentration. For light buildup or routine maintenance, vinegar is fine. For established scale deposits, use citric acid or a commercial descaling product.
Key signs of limescale buildup include: clothes feeling rough or stiff after washing, white chalky residue on dark garments, reduced water flow during cycles, longer cycle times, a musty smell that persists despite cleaning, and visible white crust around the detergent dispenser or door seal.
Yes, Calgon and similar water softening additives work by binding to the calcium and magnesium ions in hard water before they can deposit as scale. Used with every wash in hard water areas, they protect the heating element (the most vulnerable component) from scale buildup. They are most effective as prevention — removing established scale requires a dedicated descaling cycle.
The descaling process is similar for both, but front-loaders are generally more affected by hard water because their lower water levels during the wash concentrate minerals. Many front-loaders have a dedicated Drum Clean or Tub Clean cycle — use this setting for descaling. Top-loaders can be paused mid-fill for a 30-minute soak to maximise the descaler's contact time.
Call a certified technician if: descaling does not restore normal performance after 2 cycles, the machine is not heating water at all (a sign the heating element may be failed beyond scale damage), water is not draining, or the machine displays error codes. Our $89 diagnostic fee is waived when you proceed with repair.