Carrier Transicold 69NT40-561-001, Руководство по эксплуатации и обслуживанию

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T-340 7–20
7.18.2 Removing the Solenoid Valve
1. Pump down the compressor (see Section 7.4 ) and frontseat both suction and discharge valves.
2. Remove the valve. The preferred method of removing the solenoid valve is to cut the connection between
the brazed section and the valve, using a small tube cutter. Remove the valve.
Alternately, heat inlet and outlet connections to valve body and remove valve.
3. Clean the valve stem with mild cleaner, if necessary.
7.18.3 Installing the Solenoid Valve
1. Fit the new solenoid valve into position and braze. Use a wet rag to keep valve cool whenever brazing.
7.18.4 Installing the Solenoid Valve Coil:
1. Install the brass spacer on the valve stem.
2. Lubricate both o-rings with silicone provided in the kit.
3. Install bottom coil o-ring on the valve stem.
4. Install the solenoid coil on the valve stem.
5. Place the top coil o-ring on the coil mounting screw and secure the coil to the valve using a torque wrench.
Torque the screw to 25 in-lbs.
6. Connect coil wires using butt-splices and heat shrink tubing.
7.19 Economizer Expansion Valve (EXV)
The economizer expansion valve (EXV) is an automatic device that maintains constant superheat of the refrigerant
gas leaving at the point of bulb attachment, regardless of suction pressure.
Unless the valve is defective, it seldom requires maintenance other than periodic inspection to ensure that the ther
-
mal bulb is tightly secured to the suction line and wrapped with insulating compound.
NOTE
The economizer expansion valve is a hermetic valve, it does not have adjustable superheat (see Figure 7.13 ).
Figure 7.13 Economizer Expansion Valve
7.19.1 Removing the Economizer Expansion Valve
1. Pump down the compressor (see Section 7.4 ) and frontseat both suction and discharge valves. Evacuate if
unit is not equipped with service valves (see Section 7.6.1 ).
2. Turn unit power off and remove power from the unit.
3. Remove cushion clamps located on the inlet and outlet lines.
4. Remove insulation (Presstite) from expansion valve bulb.
5. Unstrap the bulb, located on the economizer line.
Inlet
Outlet