Is It an Emergency?

A small drip from a fitting or valve is not an emergency — but schedule service soon. A large leak, water pooling on the floor, or a leak near electrical components is an emergency. Shut the boiler off at the power switch and call for service.

Common Causes of Boiler Leaks

Pressure Relief Valve (PRV)

The most common source of boiler leaks. The PRV is a safety device that releases water if pressure gets too high. If it's dripping, the system pressure may be too high, or the valve itself may be failing. Either way, this needs a technician.

Corroded Pipes or Fittings

Chicago's older housing stock means many boilers have original pipes from the 1950s–1980s. Corrosion at joints and fittings is common. A technician can usually repair individual fittings without replacing the whole system.

Pump Seal Failure

The circulator pump has seals that wear over time. A leaking pump seal usually shows as a drip from the pump body. Pump replacement is a straightforward repair.

Heat Exchanger Crack

A cracked heat exchanger is a more serious problem. If the boiler is old and the heat exchanger is leaking, replacement is usually the right call.

What to Do While Waiting for Service

Place a bucket or towels under the leak. Don't add water to the system unless you know what you're doing — overfilling can make the pressure problem worse. If the leak is large or near electrical components, shut the boiler off.