Boiler runs but radiators or baseboards stay cold

Safety first: Piping can be hot; use gloves.

• Feel the pipes: If the boiler is hot but supply and return pipes to the system remain cool, circulation is not occurring.
• Check circulator: Listen and feel the circulator pump. If it is silent and cold during a call for heat, check its power connection and any pump relay on the Pennco control.
• Inspect valves: Ensure all isolation valves and zone valves are open and operating.
• Bleed air: Open air vents on radiators and near the boiler to remove trapped air that can stop flow.
• If pump is powered but not moving water: The circulator may be seized or failed and should be replaced.