Service & Repair Kits – Models 2901099700 & 2902016100

Two valve-service kits engineered for rotary screw air compressors in the 37–55 kW class (GA-frame family). 2901099700 is a minimum-pressure valve (MPV) repair kit — the valve that holds system pressure at the separator outlet, prevents air backflow into the sump, and ensures the compressor loads/unloads cleanly. 2902016100 is an inlet-valve (loading valve) service kit — the poppet assembly that controls free air delivery by opening/closing the airend intake under signal from the controller. Both kits consolidate all wear-items (seals, springs, O-rings, poppet components) so a single order covers a full valve refresh without piecemeal sourcing.

Key Features

• 2901099700 (MPV kit): Spring, valve seat, O-ring set, retaining clip — restores the 3.5–4.5 bar crack pressure typical on 37–55 kW frames

  
  

• 2902016100 (Inlet valve kit): Poppet, spring pack, piston seal, O-ring set, actuating diaphragm hardware — covers both pneumatic-actuated and servo-actuated inlet designs

  
  

• Viton O-rings standard for continuous 80–100 °C oil-mist service; NBR secondary seals on low-temp positions

  
  

• All elastomers compounded for PAO- and ester-based compressor synthetics (ISO VG 46)

  
  

• Direct-fit to the OEM valve body — no machining, no shimming

  
  

Technical Specifications

Application Guidance

Both kits serve GA37, GA45, GA55-class fixed-speed and VSD screw compressors used in workshops, light manufacturing, food-processing, and pneumatic-conveying systems.

2901099700 – Symptoms calling for MPV rebuild: separator ΔP climbs prematurely (>0.8 bar clean→dirty spread narrowing), oil carryover rises >5 ppm, or the compressor "creeps" air back into the sump on unload (you'll hear hiss at the separator housing after stop). The MPV lives at the separator outlet elbow — depressurize, unbolt the valve body (25–35 N·m when reassembling), swap spring + seat + O-rings from the kit.

2902016100 – Symptoms calling for inlet-valve service: slow load/unload transition, "hang" at part-load, or the compressor fails to reach full flow despite controller calling 100 %. The inlet valve sits on the airend intake; remove the actuator, unbolt the flange (20–30 N·m), rebuild poppet + spring + seals. On pneumatic-actuated versions, also check the pilot line for restriction — a clogged pilot orifice mimics a bad valve.

⚠️ Both valves see oil-mist at 80–95 °C continuously. If the existing O-rings look swollen or flattened, move the whole machine to Viton trim — NBR is acceptable but Viton doubles service life in hot loops.

Installation Notes

1. Lock out electrics, vent receiver and oil circuit to 0 bar before touching either valve.

   
   

2. MPV (2901099700): Unbolt valve body from separator outlet elbow. Mark spring orientation — the closed-coil end faces the seat. Lubricate new O-rings with fresh compressor oil, torque body bolts evenly (25–35 N·m). Check crack pressure with a gauge tee at the separator outlet after reassembly; should hold 3.5–4.5 bar before lift-off.

   
   

3. Inlet valve (2902016100): Remove actuator (pneumatic piston or servo motor). Unbolt flange, lift old poppet, clean seat bore with lint-free cloth. Fit new poppet seal + spring, torque flange bolts cross-pattern (20–30 N·m). Reconnect actuator, cycle load/unload manually, watch for smooth transition (typically 0→100 % in 2–4 s).

   
   

4. Run 5 min, recheck for leaks at valve body and actuator fittings.

   
   

5. Log service hours, crack pressure (MPV), and load/unload timing (inlet valve).

   
   

Quality

• O-rings & seals compounded for 80–100 °C continuous oil-mist (PAO/ester)

  
  

• Spring rate matched to OEM crack pressure (MPV) / stroke force (inlet)

  
  

• Poppet & seat finish per OEM surface-roughness spec (Ra ≤ 0.8 on seat)

  
  

• Batch-checked for dimensional conformity to valve-body bore

  
  

Ordering

Specify 2901099700 (MPV repair kit, 37–55 kW frames) or 2902016100 (inlet/loading valve kit, 37–55 kW frames). Each kit ships with component checklist. Provide compressor model + serial number to confirm sub-revision — GA37 vs. GA55 MPV seat angle and inlet-valve actuator type (pneumatic vs. servo) vary across builds.

All values nominal; confirm crack pressure, actuator type, and flange bolt torque against your machine's service manual before installation.