Test the boiler under load, check the expansion tank, inspect the relief valve, look at your basement supply lines, and test your hose bibs. These five checks take about an hour in October and prevent most of the no-heat calls we get in January. Here’s how to do each one.
1. Test the boiler under load
Fire up the boiler on a mild fall day and run the system for an hour. Watch the pressure gauge, check that every zone is calling and heating correctly, and listen for unusual sounds. A noisy circulator bearing in October is a $300 repair. The same bearing failing at 11pm in February is a $300 repair plus after-hours rates plus unhappy tenants. Our boiler and heating service covers annual pre-season checks.
2. Check the expansion tank
A waterlogged expansion tank causes pressure swings that stress the boiler and relief valve. Press the Schrader valve on the tank. If water comes out instead of air, the tank is waterlogged. This is a half-hour fix that prevents relief valve failures and pressure spikes.
3. Inspect the relief valve
Pull the lever briefly to make sure it lifts and reseats cleanly. If it dribbles after you release it, it needs replacement. Relief valves that stick open dump pressure (and your heat) into the drain.
4. Look at your supply lines in the basement
Galvanized supply lines in older buildings show deterioration at the joints first. Look for white mineral deposits or rust staining. Either indicates a joint that’s past its service life and likely to fail under winter thermal cycling. Our plumbing service covers supply line inspection and replacement.
5. Check your outdoor hose bibs
Freeze-proof hose bibs prevent split pipes at the foundation, but only if they’re installed correctly. Test that the valve fully closes and that water stops flowing immediately. If there’s a trickle after shutoff, the seat is worn and it will freeze.
If you’d rather have us do the walkthrough, our commercial and property maintenance program covers pre-season mechanical room checks for multi-family buildings across Brooklyn and Queens.