Danfoss CXH Installation guide

Instructions

Danfoss scroll compressors

CXH

A: Model number

D: Supply voltage, Starting current & Maximum operating current

B: Serial number

E: Housing service pressure

C: Refrigerant

F: Factory charged lubricant

Installation and servicing of the compressor by qualified personnel only. Follow

these instructions and sound refrigeration engineering practice relating to

installation, commissioning, maintenance and service.

R410A

CXH140

These Danfoss scroll compressors are protected against overheating

and overloading by an internal safety motor protector. However, an ex-

ternal manual reset overload protector is recommended for protecting

the circuit against over-current.

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LPS

180 s

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LLSV

The compressor must only be

Under all circumstances,

used for its designed purpose(s)

the

EN378

(or

other

and within its scope of application

applicable

local

safety

Fuses.....................................................................

(refer to «operating limits»).

regulation)

requirements

Compressor contactor....................................

Consult Application guidelines and

must be fulfilled.

Control relay.......................................................

Safety lock out relay

datasheet available from cc.danfoss.

Pump-down pressure switch...........................

com

High pressure safety switch............................

The compressor is delivered under

The

compressor

must

Control device....................................................

Liquid Line Solenoid valve

LLSV

nitrogen gas pressure

(between

handled with caution in the

Discharge gas thermostat............................

DGT

0.3 and 0.7 bar) and hence can-

vertical position

(maximum

Fused disconnect...............................................

not be connected as is; refer to

offset from the vertical : 15°)

Compressor motor.............................................

the «assembly» section for further

Safety pressure switch....................................

LPS

details.

Control circuit ....................................................

AllWiring diagrams are with pump-down cycle

1 – Introduction

These instructions pertain to the Danfoss scroll compressors CXH used for air-conditioning systems. They provide necessary information regarding safety and proper usage of this product.

2 – Handling and storage

• Handle the compressor with care. Use the

dedicated handles in the packaging. Use the compressor lifting lug and use appropriate and safe lifting equipment.

•Store and transport the compressor in an upright position.

•Store the compressor between -35°C and 50°C.

•Don’t expose the compressor and the packaging to rain or corrosive atmosphere.

3 – Safety measures before assembly

Never use the compressor in a flammable atmosphere.

•The compressor ambient temperature may not exceed 50°C during off-cycle.

•Mount the compressor on a horizontal flat surface with less than 3° slope.

•Verify that the power supply corresponds to the compressor motor characteristics (see nameplate).

FRCC.PI.032.A3.02 - 8510269P01B

•When installing CXH, use equipment specifically reserved for HFC refrigerants which was never used for CFC or HCFC refrigerants.

•Use clean and dehydrated refrigeration-grade copper tubes and silver alloy brazing material.

•Use clean and dehydrated system components.

•The piping connected to the compressor must be flexible in 3 dimensions to dampen vibrations.

4 – Assembly

•In parallel assemblies of CXH the compressor requires a rigid mounting on the rails. Use the rigid spacers from the tandem mounting kit or the rigid spacers delivered with dedicated tandem compressors.

•Slowly release the nitrogen holding charge through the schrader port.

•Remove the gaskets when brazing rotolock connectors.

•Always use new gaskets for assembly.

•Connect the compressor to the system as soon as possible to avoid oil contamination from ambient moisture.

•Avoid material entering into the system while cutting tubes. Never drill holes where burrs cannot be removed.

•Braze with great care using state-of-the-art technique and vent piping with nitrogen gas flow.

•Connect the required safety and control devices. When the schrader port is used for this, remove the internal valve.

5 – Leak detection

Never pressurize the circuit with oxygen or dry air. This could cause fire or explosion.

• Pressurize the system on HP side first and then on LP side. Never let the pressure on LP side exceed the pressure on HP side with more than 5 bar. Such pressure difference could cause internal compressor damage.

• Do not use dye for leak detection.

• Perform a leak detection test on the complete system.

• The test pressure must not exceed :

Models	LP side	HP side
CXH140	33.3 bar	45.5 bar

• When a leak is discovered, repair the leak and repeat the leak detection.

6 – Vacuum dehydration

•Never use the compressor to evacuate the system.

•Connect a vacuum pump to both the LP & HP sides.

•Pull down the system under a vacuum of 500 µm Hg (0.67 mbar) absolute.

•Do not use a megohmmeter nor apply power to the compressor while it is under vacuum as this may cause internal damage.

7 – Electrical connections

•Switch off and isolate the main power supply. See overleaf for wiring details.

•Allelectricalcomponentsmustbeselectedasper local standards and compressor requirements.

•Refer to page 2 for electrical connections details.

• The Danfoss scroll compressors only works correctly in one rotation direction. Line phases L1, L2, L3 must absolutely be connected to compressor terminals T1, T2, T3 to avoid reverse rotation.

•Use ø 4.8 mm (3/16”) screws and ¼” ring terminals for the power connection. Fasten with 3 Nm torque.

Danfoss A/S, 6430 Nordborg, Denmark

•The thermostat connection (if present) is a ¼” AMP-AWE spade connector.

•The compressor must be connected to earth with the 5 mm earth terminal screw.

8 – Filling the system

•Keep the compressor switched off.

•Fill the refrigerant in liquid phase into the condenser or liquid receiver. The charge must be as close as possible to the nominal system charge to avoid low pressure operation and excessive superheat. Never let the pressure on LP side exceed the pressure on HP side with more than 5 bar. Such pressure difference could cause internal compressor damage.

•Keep the refrigerant charge below the indicated charge limits if possible. Above this limit; protect the compressor against liquid flood-back with a pump-down cycle or suction line accumulator.

•Never leave the filling cylinder connected to the circuit.

Compressor models	Refrigerant charge
	limit (kg)
CXH140	7.9

9 – Verification before commissioning

Use safety devices such as safety pressure switch and mechanical relief valve in compliance with both generally and locally applicable regulations and safety standards. Ensure that they are operational and properly set.

Check that the settings of high-pressure switches and relief valves don’t exceed the maximum service pressure of any system component.

•A low-pressure switch is recommended to avoid vacuum operation. Minimum setting for CXH: 1.5 bar g.

•Verify that all electrical connections are properly fastened and in compliance with local regulations.

•When a crankcase heater is required, it must be energized at least 6 hours before initial startup and start-up after prolonged shutdown for sump heaters.

10 – Start-up

•Never start the compressor when no refrigerant is charged.

•All service valves must be in the open position.

•Balance the HP/LP pressure.

•Energize the compressor. It must start promptly. If the compressor does not start, check wiring conformity and voltage on terminals.

•Eventual reverse rotation can be detected by following phenomena; the compressor doesn’t build up pressure, it has abnormally high sound level and abnormally low power consumption. In such case, shut down the compressor immediately and connect the phases to their proper terminals. CXH140 has no internal reverse rotation protection. Prolonged reverse rotation will damage the compressors.

•If the internal overload protector trips out it must cool down to 60°C to reset. Depending on ambient temperature, this may take up to several hours.

11 – Check with running compressor

•Check current draw and voltage.

•Check suction superheat to reduce risk of slugging.

•Observe the oil level in the sight glass (if provided) for about 60 minutes to ensure proper oil return to the compressor.

•Respect the operating limits.

•Check all tubes for abnormal vibration. Movements in excess of 1.5 mm require corrective measures such as tube brackets.

•When needed, additional refrigerant in liquid phase may be added in the low-pressure side as far as possible from the compressor. The compressor must be operating during this process.

•Do not overcharge the system.

•Never release refrigerant to atmosphere.

•Before leaving the installation site, carry out a general installation inspection regarding cleanliness, noise and leak detection.

•Record type and amount of refrigerant charge as well as operating conditions as a reference for future inspections.

12 – Maintenance

Internal pressure and surface temperature are dangerous and may cause permanent injury. Maintenance operators and installers require appropriate skills and tools. Tubing temperature may exceed 100°C and can cause severe burns.

Ensure that periodic service inspections to ensure system reliability and as required by local regulations are performed.

To prevent system related compressor problems, following periodic maintenance is recommended:

•Verify that safety devices are operational and properly set.

•Ensure that the system is leak tight.

•Check the compressor current draw.

•Confirm that the system is operating in a way consistent with previous maintenance records and ambient conditions.

•Check that all electrical connections are still adequately fastened.

• Keep the compressor clean and verify the absence of rust and oxidation on the compressor shell, tubes and electrical connections.

13 - Warranty

Alwaystransmitthemodelnumberandserialnumber with any claim filed regarding this product.

The product warranty may be void in following cases:

•Absence of nameplate.

•External modifications; in particular, drilling, welding, broken feet and shock marks.

•Compressor opened or returned unsealed.

•Rust, water or leak detection dye inside the compressor.

•Use of a refrigerant or lubricant not approved by Danfoss.

•Any deviation from recommended instructions pertaining to installation, application or maintenance.

•Use in mobile applications.

•Use in explosive atmospheric environment.

•No model number or serial number transmitted with the warranty claim.

14 – Disposal

Danfoss recommends that compres sors and compressor oil should be recycled by a suitable company at its site.

Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products already on order provided that such alterations can be made without subsequential changes being necessary in specifications already agreed.

FRCC.PI.032.A3.02 - 8510269P01B