The usual suspects
A small system leak
A weeping radiator valve or fitting — often hidden under floors, announced only by the gauge.
A waterlogged expansion tank
When its air cushion fails, pressure swings wildly and the relief valve starts dumping.
A passing relief valve
A safety valve that never fully reseats dribbles pressure away down its pipe.
Bleeding without topping up
Every radiator bleed removes water — if no one re-pressurizes after, the gauge slides.
Find the leak once.
Radiator valves, relief valves and expansion tanks are the usual suspects — we chase it to the source, price upfront.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
Worth trying first (5 minutes, free)
- 1
Watch the gauge for a week: note how fast it falls — psi per day tells us leak size.
- 2
Look for the drips: radiator valves, visible pipes, and the relief valve’s discharge pipe (is it damp?).
- 3
Top up to ~12–15 psi via the filling loop if you know it — and count how often you must.
Still not working? Then it’s a technician job — and the sooner it’s booked, the sooner the house is comfortable again. Book the visit →
Stop and book a pro if…
- Pressure falls within hours, not weeks.
- The relief valve pipe drips constantly.
- Ceiling or floor stains near heating pipes.
- The boiler locks out on low pressure repeatedly.
Why homeowners hand it to us
- You approve the price first. Upfront quote before a single screw turns.
- Same-day service. Book in a minute, hear from a tech within 1 business hour.
- 500+ jobs done by 4.9★ rated, professional technicians.
- Fixed right, guaranteed. If it’s not right, we make it right.
Quick answers
Is topping up bad for the boiler?
Occasionally, no. Weekly, yes — fresh water brings oxygen and minerals that corrode and scale the system from the inside. The leak is always cheaper than the habit.
How do you find a hidden leak?
Pressure-drop patterns, inspection of every accessible fitting, and isolating zones to bracket the loss. Most "hidden" leaks are at accessible valves — floors-up demolition is the rare case, and you’d approve any step first.
What if it’s the expansion tank?
A routine swap that instantly stabilizes pressure — and one of the most common answers. Upfront-priced at the visit.
Done guessing?
Every top-up adds fresh, mineral-rich water that ages the system. Book the real fix.
Book My Same-Day Visit60 seconds online · or call (206) 486-6373
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