Troy-Bilt MXZ-3A30NA, MXZ-4A36NA Purging Procedures, Leak Test, And Test Run, Gas Charge

4. PURGING PROCEDURES, LEAK TEST, AND TEST RUN

4-1. PURGING PROCEDURES AND LEAK TEST

1)	Remove service port cap of stop valve on the side of the outdoor unit
	gas pipe. (The stop valve will not work in its initial state fresh out of the
	factory, totally closed with cap on.)
2)	Connect gauge manifold valve and vacuum pump to service port of
	stop valve on the gas pipe side of the outdoor unit.
3)	Run the vacuum pump. (Vacuumize for more than 15 minutes.)
4)	Check the vacuum with gauge manifold valve, then close gauge mani-
	fold valve, and stop the vacuum pump.
5)	Leave as it is for one or two minutes. Make sure pointer gauge mani-
	fold valve remains in the same position. Confirm that pressure gauge
	shows –0.101 Mpa [Gauge] [–760 mm Hg (–30 in. Hg)].
6)	Remove gauge manifold valve quickly from service port of stop valve.
7)	After refrigerant pipes are connected and evacuated, fully open all
	stop valves on both sides of gas pipe and liquid pipe. Operating with-
	out fully opening lowers the performance and this causes trouble.
8)	Refer to 1-4., and charge the prescribed amount of refrigerant if
	needed. Be sure to charge slowly with liquid refrigerant. Otherwise,

		–0.101MPa	Compound pressure
		[–760 mm Hg
*4 to 5 turns	Stop valve cap	(–30 in. Hg)]	gauge (for R410A)
*Close	(Torque 19.6 to 29.4 N•m,		Pressure gauge
	200 to 300 kgf•cm, 15 to		(for R410A)
*Open	22 ft•lb)		Gauge manifold
		Stop valve	valve (for R410A)
Hexagonal wrench		for GAS Handle	Handle High
		Low	Charge hose
			(for R410A)
Service port cap
(Torque 13.7 to
17.7 N•m, 140 to

180 kgf•cm, 10 to
13 ft•lb)	Vacuum pump
Stop valve	(for R410A)
for LIQUID

composition of the refrigerant in the system may be changed and af-

fect performance of the air conditioner.

9) Tighten cap of service port to obtain the initial status.

10) Leak test

Precautions when using the control valve

ControlA
valveOpen	Service port
Close
Body	Charge hose
	(for R410A)

When attaching the control valve to the service port, valve core may de- form or loosen if excess pressure is applied. This may cause gas leak.

When attaching the control valve to the service port, make sure that the valve core is in closed position, and then tighten part A. Do not tighten part A or turn the body when valve core is in open position.

4-2. GAS CHARGE

Perform gas charge to unit.

1 Connect gas cylinder to the service port of stop valve.

2Perform air purge of the pipe (or hose) coming from refrigerant gas cylinder.

3Replenish specified amount of the refrigerant, while operating the air conditioner for cooling.

Note:

In case of adding refrigerant, comply with the quantity specified for the refrigerating cycle.

CAUTION:

When charging the refrigerant system with additional refrigerant, be sure to use liquid refrigerant. Adding gas refrigerant may change the composi- tion of the refrigerant in the system and affect normal operation of the air conditioner. Also, charge the system slowly, otherwise the compressor will be locked.

To maintain the high pressure of the gas cylinder, warm the gas cylinder with warm water [under 40°C (140°F)] during cold season. But never use naked fire or steam.

				Union
				Stop valve
				Liquid pipe
				Union
Indoor	D	C	B	A
unit
				Union
				Stop valve with
				service port
				Gas pipe
				Union
Refrigerant gas
cylinder
operating valve				Gauge manifold
(for R410A)
				valve (for R410A)

Charge hose (for R410A)

Refrigerant gas cylinder for R410A with siphon

Refrigerant (liquid)

Electronic scale for refrigerant charging

Outdoor unit

(MXZ-4A36NA)