Water Source Heat-Pump Controller, McQuay – Mark IV replacement

Replacement for the McQuay Mark IV controllers


The C515 is a generic replacement for the McQuay MarkIV controllers P/N 056792401K, 60638801 and 056792402K. It wires exactly the same and is dimensionally identical to the original board. It has two significant advantages, one lower price and the fact that it can activate both a 24 VDC reversing solenoid and a 24 VAC reversing solenoid selectable by a jumper.

Solid State lockout Circuit with Fault indication (HPS, LPS, LTS, Condensation and Under / Over voltage).
USD, CSD and ESD inputs.
Three relays controls the: Compressor, Fan and RV.
5 Minutes Anti-Short Cycle protection and 5 inputs for monitoring fault sensors.
Random start.
4 Diagnostics LED’s.
Intelligent reset logic.
Test mode.
Communication with the ET thermostat.
Cassis mount.
Operate on 24 VAC.

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