Evaporator Expansion Valve (TXV) Replacement

Note TXV can be accessed through the evaporator access door.

  1. Perform a low side pump down or reclaim charge depending on the unit. Release the 2-3 lbs pressure from the low side.

  2. Open the evaporator access panel.

  3. Install plywood or heavy cardboard on top of coil on the left and right side. This will protect the coil from damage.

  4. Remove the left side motor and fan and position in right side opening. Do not unwire the motor the harness is long enough.

  5. Remove TXV standoff mount.

  6. Remove the panel to gain access to the TXV element.

  7. Cut the one ty band off the insulation around the element. Peel back the insulation to expose the clamp holding the element. Loosen the clamp and remove the element from the tube.

  8. Unsolder the three tubes to the TXV and remove the valve from the unit.

  9. Prepare the tubes in the unit and on the new TXV for installation.

  10. Solder in the new TXV. Use 15% silver solder 203-364.

  11. Pressurize the refrigeration system and check for leaks (Refer to Leak Testing Refrigeration System). Repair leak if required.

  12. Evacuate the system (Refer to Evacuation and Cleanup of Refrigeration System).

  13. Install element in tube on suction line. Tighten clamp. Reapply insulation around bulb and secure with a ty band.

  14. Install the element access panel and install grommets. Install TXV mount.

  15. Install left side motor and fan.

  16. Open service valves or recharge unit with R-404A/R-452A (Refer to Charging System with Refrigerant).

  17. Perform a controller pretrip test to verify system operation.

      
  1 TXV Mount
  2 Access Panel
  3 Element
  4 Tube on Suction Line
     
     
Parent topic: Refrigeration Maintenance