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22 Service 

Copeland Scroll compressors have copper plated steel suction and discharge tubes. These tubes are far more robust 
and less prone to leaks than copper tubes used on other compressors. Due to the different thermal properties of steel 
and copper, brazing procedures may have to be changed from those commonly used. For brazing of the tubes see 
Figure 11 and the following procedures. Since the discharge stub contains a check valve, care must be taken not to 
overheat it as well as to prevent brazing material from flowing into it. 
 

23 New 

Installations 

 

The copper-coated steel tubes on scroll compressors can be brazed in approximately the same manner as 
any copper tube. Recommended brazing materials: Any silfos material is recommended, preferably with a 
minimum of 5% silver. However, 0% silver is acceptable. 

 

Be sure tube fitting inner diameter and tube outer diameter are clean prior to assembly. 

 

Using a double-tipped torch apply heat in area 

 

As the tube approaches brazing temperature, move the torch flame to area 2. 

 

Heat area 2 until braze temperature is attained, moving the torch up and down and rotating around the tube 
as necessary to heat the tube evenly. Add braze material to the joint while moving the torch around the joint 
to flow braze material around the circumference. 

 

After the braze-material flows around the joint, move the torch to heat area 3. This will draw the braze-
material down into the joint. The time spent heating area 3 should be minimal. 

 

As with any brazed joint, overheating may be detrimental to the final result. 

 

 
 
 
 
Figure 11: Suction tube brazing 
 
 
 
 
 

 

24 Field 

Service 

To disconnect:  
 

 

Heat joint areas 2 and 3 slowly and uniformly until the braze material softens and the tube can be pulled out 
of the fitting. 

 
To reconnect: 
 

 

 Recommended brazing-materials: Silfos with minimum 5% silver or silver braze used on other compressors. 
Due to the different thermal properties of steel and copper, brazing procedures may have to be changed from 
those commonly used. For brazing of the tubes see Figure 11 and the following procedures. 
Since the discharge stub contains a check valve, care must be taken not to overheat it as well as to prevent 
brazing material to flow into it. 

 

C6.2.9/0203-1004/E 10 

Summary of Contents for Copeland Scroll ZH 15 K4E

Page 1: ...Scroll compressors for Dedicated Heat Pumps ZH15 K4E ZH45 K4E Application Guidelines ...

Page 2: ...perature Protection 5 10 Standard Motor Protection 6 11 Low Ambient Cut Out 6 12 Pressure Controls 6 13 Shut Off 6 14 Starting 6 15 Deep Vacuum Operation 6 16 Brief Power Interruptions 6 17 Electrical Installation 7 18 High Potential Testing 8 19 Compressor Functional Check 8 20 Excessive Liquid Floodback 9 20 1 Continuous Floodback 9 20 2 Repeated Floodback during Defrost 9 21 Installation 9 22 S...

Page 3: ...ting oils must be used Do not start the compressor until it is charged with refrigerant Correctly used the compressor and the pressure line piping may reach temperatures that may cause burning if touched Wear safety goggles when working on open systems If the refrigerant needs to be removed from the system do not disperse it in the environment use the correct equipment method of removal For storag...

Page 4: ...E Model Designation Z H 26 K 4 E TFD 524 1 2 3 4 5 6 7 8 1 Z Compressor family Z Scroll 2 H Dedicated heat pump compressor 3 Nominal heating capacity kW 50 Hz and 7 C evaporating 50 C condensing using multiplier 1 3 Ex 26K 8 6 kW 4 Nominal heating capacity multiplier K 1 M 10 5 Model variation 6 POE Oil 7 Motor version 8 Bill of Material 4 Application Envelope Tc C Te C R407C Mid point Figure 1 Ap...

Page 5: ...of the compressor Figure 2 Minimum bottom shell temperature tb One characteristic of POE is that it is far more hygroscopic than mineral oil Figure 3 Only brief exposure to ambient air is needed for POE to absorb sufficient moisture to make it unacceptable for use in a refrigeration system Since POE retains moisture chemically it is not possible to completely remove it through the use of vacuum Co...

Page 6: ...ot exceed the following values 3 6 kg for ZH 15 K4E ZH 26 K4E 4 5 kg for ZH 30 K4E ZH 45 K4E A CCH is to prevent refrigerant migrating into the shell during standstill periods It is recommended to fit a CCH if the compressor is located outside the building the system charge is above the limits shown and no accumulator is piped to provide free liquid drainage during the off cycle as shown For corre...

Page 7: ...startup low voltage starting characteristics are excellent for Copeland Scroll compressors 15 Deep Vacuum Operation The danger of pulling deep vacuums is avoided due to an internal low vacuum protection which prevents the scrolls pumping unloads when the pressure ratio exceeds approximately 20 1 In order to avoid nuisance trips it is recommended to set the low pressure control as described in Sect...

Page 8: ...n depending upon phasing of the power to L1 L2 and L3 Since there is a 50 50 chance of connecting power in such a way as to cause rotation in the reverse direction it is important to include notices and instructions in appropriate locations on the equipment to ensure proper rotation direction is achieved when the system is installed and operated Verification of proper rotation direction is made by...

Page 9: ...Compressor Functional Check It is not desirable to perform functional compressor tests where the compressor is turned on with the suction service valve closed to check how low the compressor will pull suction pressure Rather the following diagnostic procedure should be used to evaluate whether the Copeland Scroll compressor is functioning properly 1 Proper voltage to the unit should be verified 2 ...

Page 10: ...ge levels above the limits given in Section 8 it may be necessary to fit an accumulator to trap a certain amount of the returning liquid A good indication of liquid return can be low sump temperatures Figure 2 Obtain a sample compressor with a side sight tube to measure liquid level in the compressor Set the system up in a configuration with the indoor unit elevated approximately 1 m above the out...

Page 11: ...rch flame to area 2 Heat area 2 until braze temperature is attained moving the torch up and down and rotating around the tube as necessary to heat the tube evenly Add braze material to the joint while moving the torch around the joint to flow braze material around the circumference After the braze material flows around the joint move the torch to heat area 3 This will draw the braze material down ...

Page 12: ...and discharge line can briefly but repeatedly reach temperatures above 177 C as the compressor cycles on its internal protection devices Care must be taken to ensure that wiring or other materials which could be damaged by these temperatures do not come into contact with the shell 27 System Charging Procedure Rapid charging on only the suction side of a single phase Scroll equipped system or conde...

Page 13: ...ference is that the vibration characteristic of the Scroll compressor although low includes two very close frequencies one of which is normally isolated from the shell by the suspension of an internally suspended compressor These frequencies which are present in all compressors may result in a low level beat frequency that can be detected as noise coming along the suction line into a house under s...

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