Marco grabbed his multimeter. He bypassed the computer, went straight to the solenoid coil, and measured resistance. It should have been 20 ohms. It read 1.2—a dead short.
He added his own note to the PDF—a photo of the failed solenoid and a timestamp. Then he changed the filename to:
If the manual is restricted, contact an authorized Daikin/McQuay parts distributor. They can provide the exact service bulletins, parts lists, and wiring diagrams associated with your serial number. Safety First
Check the pressure drop across the oil filter. A high differential pressure ( ) indicates clogging. Every 10,000 Hours (or Annually) mcquay hsa screw compressor service manual best
: Synthetic Polyalphaolefin (PAO) or specialized mineral oils as outlined in the specific model manual. 📅 Section 3: Preventive Maintenance Schedule
The slide valve regulates the capacity of the compressor (typically from 25% to 100%). It moves longitudinally along the rotor mesh to change the suction bypass point. The service manual details the hydraulic or electronic actuator setup, piston seals, and calibration steps for the slide valve. Bearings and Thrust Assemblies
For proper service of a McQuay HSA screw compressor , technicians should follow standard maintenance procedures for single-screw compressors, emphasizing lubrication integrity and capacity control testing. The HSA series belongs to the McQuay "HallScrew" family, which utilizes a single main rotor and two gate rotors for balanced compression. Marco grabbed his multimeter
If a compressor requires a major overhaul, the manual serves as the definitive blueprint. It outlines the precise sequence for dismantling the compressor, inspecting the bearings, and reassembling the unit without damaging internal seals or rotors. Best Practices for McQuay HSA Compressor Maintenance
Page 47 stopped him cold.
McQuay HSA compressors are robust, but their internal bearings and seals will eventually wear down. A major overhaul—guided strictly by the manual—involves disassembling the compressor, replacing the main bearings, inspecting the rotors for wear, and replacing all O-rings and gaskets. Troubleshooting Common HSA Compressor Issues It read 1
There, circled in red, was a note: “If slide valve position reads correct but temp climbs, ignore the transducer. Check the unloader solenoid for internal leakage. 90% of HSAs die here.”
Field test for capacity slide movement and glyd ring tightness. Workshop-level detailed leak check of the capacity system. Lubrication and Fluids: