Shower Valve Repair · Newmarket

Scalding and pressure balance

Since the 1990s, Ontario code has required shower valves that protect against sudden temperature swings. A pressure-balancing valve uses a spool that shifts when hot or cold pressure drops, keeping the mix steady. Thermostatic valves sense temperature directly. Both can clog with scale and grit from our water, and both need their parts to move freely. Older houses may still have two-handle valves with no protection at all.

Cartridge swap

Most single-handle shower valves have a replaceable cartridge. When the handle gets tight, the temperature drifts, or the shower drips after it is shut off, a new cartridge usually solves it. We shut off water at the valve stops or the main, pull the trim, remove the old cartridge and flush the body before fitting the new one. Then we set the rotational limit stop so the lever cannot reach a scalding setting.

Behind the wall

• Leaks inside the wall show up as stains on the ceiling below or loose tiles.
• Some old valves have no access panel; we may cut one from a closet behind the shower.
• When the valve body itself is corroded, replacement means opening tile or the back wall.
• We can fit a new valve to existing tile with a wide trim plate in many cases.

1. Diagnose from the front.
2. Open access if needed.
3. Replace or rebuild the valve.
4. Test pressure and temperature, then close up.