heatcraft-refrigeration-p h-im-fl1a User Manual

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7
Phase Loss Monitor
The combination phase sequence and loss monitor relay 
protects the system against phase loss (single phasing), phase 
reversal (improper sequence) and low voltage (brownout). 
When phase sequence is correct and full line voltage is present 
on all three phases, the relay is energized as the normal 
condition indicator light glows.
NOTE: If compressor fails to operate and the normal condition 
indicator light on the phase monitor does not glow, then the 
supplied electrical current is not in phase with the monitor. This 
problem is easily corrected by the following steps:
1.  Turn power off at disconnect switch.
2.  Swap any two of the three power input wires.
3.  Turn power on. Indicator light should glow and 
compressor should start.
4.  Observe motors for correct rotation.
Recommended Refrigerant Piping Practices 
 
The system as supplied by Heatcraft Refrigeration Products
was thoroughly cleaned and dehydrated at the factory. Foreign 
matter may enter the system by way of the evaporator to 
condensing unit piping. Therefore, care must be used during 
installation of the piping to prevent entrance of foreign matter.
Install all refrigeration system components in accordance with 
applicable local and national codes and in conformance with 
good practice required for the proper operation of the system. 
The interconnecting pipe size is not necessarily the same size 
as the stub-out on the condensing unit or the evaporator. 
The following procedures should be followed: 
(a)  Do not leave dehydrated compressors or filter-driers on 
   
condensing units open to the atmosphere any longer  
   
than is absolutely necessary. 
(b)  Use only refrigeration grade copper tubing, properly  
   
sealed against contamination.  
(c)  Suction lines should slope 1/4" per 10 feet towards the 
   
compressor. 
 
  (d)  Suitable P-type oil traps should be located at the base of 
   
each suction riser of four (4) feet or more to enhance oil  
   
return to the compressor. 
(e)  For desired method of superheat measurement,  
   
a pressure tap should be installed in each evaporator  
   
suction line in the proximity of the expansion valve bulb. 
(f)  When brazing refrigerant lines, an inert gas  should  
   
be passed through the line at low pressure to  
   
prevent scaling and oxidation inside the tubing.  
   
Dry nitrogen is preferred.  
(g)  Use only a suitable silver solder alloy on suction and  
   
liquid lines. 
(h)  Limit the soldering paste or flux to the minimum  
   
required to prevent contamination of the solder  
   
joint internally. Flux only the male portion of the  
   
connection, never the female. After brazing, remove  
   
excess flux. 
(i)  If isolation valves are installed at the evaporator, full port 
   
ball valves should be used.
Figure 4. Example of Pipe Support
Refrigerant Pipe Support
 
 
  1.  Normally, any straight run of tubing must be supported  
   
in at least two locations near each end of the run. Long  
   
runs require additional supports. The refrigerant lines  
   
should be supported and fastened properly. As a guide,  
   
3/8 to 7/8 should be supported every 5 feet; 1-1/8 and  
   
1-3/8 every 7 feet; and 1-5/8 and 2-1/8 every 9 to 10  
   
feet. 
2.  When changing directions in a run of tubing, no corner  
   
should be left unsupported. Supports should be placed a  
   
maximum of 2 feet in each direction from the corner. 
3.  Piping attached to a vibrating object (such as a  
   
compressor or compressor base) must be supported  
   
in such a manner that will not restrict the movement  
   
of the vibrating object. Rigid mounting will fatigue the  
   
copper tubing. 
4.  Do not use short radius ells. Short radius elbows have  
   
points of excessive stress concentration and are subject 
   
to breakage at these points. 
5.  Thoroughly inspect all piping after the equipment  
   
is in operation and add supports wherever line vibration  
   
is significantly greater than most of the other piping. 
   
Extra supports are relatively inexpensive as compared  
   
to refrigerant loss.
Figure 5. Condensing Unit / Compressor to Wall Support.