Before You Start: Confirm It's the Boiler
In a typical Greater Vancouver mechanical room, a boiler sits among water lines, a hot water tank, sometimes a softener, and drain pipes. The first job is to confirm the drip is genuinely from the boiler and not condensation or a neighbouring fitting.
Dry everything thoroughly, then place dry paper towel or cardboard directly under the boiler and around the pipes feeding it. Check back in an hour or two. Fresh water that reappears specifically beneath the boiler casing or its connections confirms a real boiler drip worth tracing.
A crucial safety note before you go further: if there's any gas smell or your CO alarm sounds, stop immediately. Leave the home, call FortisBC at 1-800-663-9911 or 911 from outside, then call us at 604-359-1081 when you're safe.
Check 1: The Pressure Gauge and Discharge Pipe
Start with the easiest and most common cause. Read the pressure gauge on the front of the boiler. A normal cold reading is about 1.0–1.5 bar. If it's sitting above 2.5 bar, the system is over-pressurised and the relief valve may be discharging — which can drip down and appear underneath the unit.
Then find the relief valve discharge pipe, which usually routes outside. If it's wet or dripping, the relief valve has lifted and your "underneath" drip is actually escaping pressure. The cause behind that is typically a waterlogged expansion vessel or an open filling loop.
While you're there, confirm the filling loop (the small braided silver hose) has both valves fully closed. An open loop slowly over-pressurises the system and is a frequent, easily-missed cause.
Check 2: Pump, Air Vent, and Pipe Fittings
Look directly up from where the water is collecting. The drip is being pulled down by gravity, so the source is usually somewhere above the puddle. Inspect the circulator pump for water or limescale crusting around its body — a failing pump seal weeps and drips straight down.
Check the auto air vent (a small brass cylinder, often near the top of the unit) for seepage, and run your eye along the visible pipe fittings and unions for moisture or white limescale trails that mark where water has been evaporating. Metro Vancouver's water leaves these telltale deposits over time.
Don't dismantle anything. You're looking and reporting, not repairing — these observations let our technician arrive with the right parts and go straight to the source.
Check 3: Signs of Something More Serious
A few signs warrant a faster call. Rust-coloured or brown water suggests internal corrosion, possibly at the heat exchanger. A pressure gauge that drops steadily over days means water is escaping somewhere internal. And if the boiler keeps locking out or won't fire, the leak may be affecting its operation.
These point beyond simple seal-and-valve territory toward the pump, the expansion system, or the heat exchanger — components that need a Red Seal gas fitter to diagnose and, in some cases, that tip an older boiler toward replacement.
Note what you see (colour of the water, gauge behaviour over a day, any error codes) and share it when you call. The more detail, the faster and more accurately we can help.
When to Call GasBoilers.ca
If the drip persists, if you can't find an obvious harmless source, or if you spot any of the more serious signs above, it's time for a professional. Switch the boiler off, protect your floor, and stop re-pressurising a leaking system.
GasBoilers.ca, a CanroHeat Division, covers Vancouver, Burnaby, Richmond, Surrey, Coquitlam, the North Shore and the wider Lower Mainland. We trace drips to their true source, fix what's economical, and give honest replace-versus-repair advice when needed. Call 604-359-1081 to book — same-day and weekend service available where possible.