Radiant heating manifold annual maintenance checklist

Occupants told which floors go cool and drain hoses run

Owner and occupants told which zones are off and for how long, water let cool before draining, purge hoses run to a drain or container clear of finishes.

Circulator, zone controller and any mixing station locked and tagged

Every power source feeding the manifold locked by each worker; refilled and vented, then the temporary release for hot checks (people clear, locks off by their owners), re-locked before hands go in.

Each loop isolated and purged clear of air and debris

Loops purged one at a time to the drain until the water runs clear and air-free, isolation and purge valves operating without seizing.

System water and treatment checked

Fill water and treatment confirmed against the manufacturer's guidance, no visible rust or sludge in the purge stream, glycol condition logged where used.

System refilled to the cold-fill pressure after the purge

Fill valve or makeup brings the system back to its cold-fill setting on the manifold gauge, vents bled again, no loop left drained or valved off.

Zone controller terminations checked before power returns

Torque-verified at the transformer primary, low-voltage leads at the wiring center and actuators checked secure, no heat marks or pinched cable, before the temporary release.

Every actuator removed, seat checked and re-cycled

Actuators pulled and the valve pins move freely by hand, seats clean, actuators reseated and confirmed cycling on a call.

Circulator and mixing valve exercised through range

Pump runs smooth with no bearing noise, mixing valve driven through its range and holding the supply temperature it targets.

Floor supply high limit tested where a limit control is fitted

Limit tripped through its own test function or a setpoint change, hot water to the floor stopped, then reset; test kept short so no floor overheats.

Manifold rebalanced to the loop schedule after purging

Each flow meter set to its scheduled flow with the system hot and running, settings recorded on the manifold log, no loop left starved.

Return temperature compared at every loop port after balancing

Each loop's return port read with an IR thermometer once the system settles, a loop running much colder than its neighbors traced for air or blockage.

Each thermostat opens only the loops tagged for its room

One zone raised at a time, only the actuators on that room's tagged loops open, any mismatch in wiring or tags recorded and the loop schedule updated.

Floor surface temperatures surveyed in every zone

Beyond the quarterly spot read, each zone scanned with an IR camera once up to temperature, against the surface limit and last year's survey, cold areas noted.

Locks removed by whoever hung them and zones returned to auto

Locks and tags removed by the person who applied them, pump and heat source in auto, thermostats back to the owner's setpoints, drain hoses off and caps on.

Loop flows, temperatures and floor changes recorded for the owner

Final flow per loop, temperatures, pressure, water treatment result and any reported floor covering changes recorded against the manifold tag, repairs listed.