Closed HVAC loops are out of sight. By the time corrosion shows as a fouled coil or a leaking valve, the damage has been running for months at an inhibitor level nobody was measuring.
The Operating Reality
A closed heating or chilled water loop serves fan coils, air handlers and heat exchangers in a commercial building or campus, with make-up water and a dosing point on the return line.
Why Manual Dosing Falls Short
Make-up dilutes inhibitor and carries in fresh oxygen and hardness. Manual top-up gives a saw-tooth concentration: protected right after dosing, unprotected before the next round.
How Automatic Chemical Dosing Fits
- Automatic feed holds the band flat, lifting corrosion protection substantially compared with intermittent manual dosing.
- Controller feedback from pH, ORP and conductivity runs with an error under ±5% and adapts to the loop’s own pattern.
- 316L wetted parts and compatible materials handle chlorinated make-up water in HVAC duty.
Selection Checklist
- Define the control signal first (pH, ORP, conductivity or flow-proportional) before sizing the pump.
- Size the metering pump to the lowest expected dose with margin, not to the peak dose.
- Confirm chemical compatibility of wetted parts (316L, PVC, PVDF) with every product to be fed.
- Provide containment, leak detection and dry-running protection in the dosing room design.
- Integrate the skid with PLC, DCS or remote telemetry so dose is visible in the control room.
Related Products
- Automatic Chemical Dosing System
- Automatic Condenser Tube Cleaning System (ATCS)
- Constant Pressure Water Make-up System
FAQ
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