Section 8. Refrigerant Line Leak Check; Section 9. Evacuation; Section 10. Service Valves - Trane 5TTR5018 Installation And Operation Manual

Section 8. Refrigerant Line Leak Check

8.1 Check For Leaks
After completion of field piping for split systems, the field pipework shall be pressure tested with nitrogen and then
vacuum tested prior to refrigerant charging, according to the following requirements:
1. The minimum leak test pressure of the lineset and indoor coil shall be the high side design pressure, unless the
high side of the system, cannot be isolated from the low side of the system in which case the entire system
shall be pressure tested to the low side design pressure.
2. The test pressure after removal of pressure source shall be maintained for at least 1 hour with no decrease of
pressure indicated by the test gauge, with test gauge resolution not exceeding 5% of the test pressure.
Important: Under no circumstances shall potential sources of ignition be used in the searching for or detection of
refrigerant leaks.
Important: The following leak detection methods are deemed acceptable for all refrigerant systems:
• Electronic leak detectors calibrated for R454B
• Bubble method
STEP 1 - Pressurize the refrigerant lines and evaporator coil to 150 PSIG using dry nitrogen.
STEP 2 - Check for leaks by using a soapy solution or bubbles at each brazed location.
Note: Remove nitrogen pressure and repair any leaks before continuing.
STEP 3 - Once the initial leak check is complete, complete a system pressure test. Pressurize the system to the
design pressure of the system for a minimum of 60 minutes. Do not add additional refrigerant or test gas after
reaching the design pressure. The system should show no loss of pressure once pressurized. Once the pressure
test is complete follow the steps for evacuation.

Section 9. Evacuation

9.1 Evacuate the Refrigerant Lines and Indoor Coil
Important: Do not open the service valves until the refrigerant lines and indoor coil leak check and evacuation
are complete.
STEP 1 - Evacuate until the micron gauge reads no higher than 350 microns, then close off the valve to the
vacuum pump.
STEP 2 - Observe the micron gauge. Evacuation is complete, if the micron gauge does not rise above
500 microns in one (1) minute and 1500 microns in ten (10) minutes.
Once evacuation is complete, blank off the vacuum pump and micron gauge, and close the valve on the manifold
gauge set.

Section 10. Service Valves

10.1 Open the Gas Service Valve
Important: Leak check and evacuation must be completed before opening the service valves.
NOTE: Do not vent refrigerant gases into the atmosphere.
STEP 1 - Remove valve stem cap.
STEP 2 - Using an adjustable wrench, turn valve stem 1/4 turn counterclockwise to the fully open position.
STEP 3 - Replace the valve stem cap to prevent leaks. Tighten finger tight plus an additional 1/6 turn.
8 18-AC129D1-1B-EN