Friedrich H)A24K75L Manual Do Utilizador

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Remove the leads from the compressor terminals and set  

the ohmmeter on the lowest scale (R x 1). 

Touch the leads of the ohmmeter from terminals common  

to start (“C” to “S”). Next, touch the leads of the ohmmeter  

from terminals common to run (“C” to “R”).

Add values “C” to “S” and “C” to “R” together and check 

resistance from start to run terminals (“S” to “R”).  Resistance 

“S” to “R” should equal the total of “C” to “S” and “C” to “R.”  

 

In  a  single  phase  PSC  compressor  motor,  the  highest  

value will be from the start to the run connections (“S” to  

“R”). The next highest resistance is from the start to the  

common connections (“S” to “C”). The lowest resistance  

is from the run to common. (“C” to “R”) Before replacing a 

compressor, check to be sure it is defective. 

Turn  off  electric  power  before  service  or 

installation.  Extreme  care  must  be  used,  if  it 

becomes  necessary  to  work  on  equipment 

with power applied.

 

Failure to do so could result in serious injury or 

death.

Many  compressor  failures  are  caused  by  the  following  

conditions: 
1.    Improper air flow over the evaporator. 

2.    Overcharged refrigerant system causing liquid to be 

returned to the compressor. 

3.    Restricted refrigerant system. 

4.    Lack of lubrication. 

5.    Liquid refrigerant returning to compressor causing oil 

to be washed out of bearings. 

6.    Noncondensables  such  as  air  and  moisture  in  

          the  system.  Moisture  is  extremely  destructive  to  a 

        refrigerant system. 

Use  an  ohmmeter  set  on  its  highest  scale.  Touch  one 

lead to the compressor body (clean point of contact as a 

good  connection  is  a  must)  and  the  other  probe  in  turn 

to each compressor terminal. If a reading is obtained the 

compressor is grounded and must be replaced.

Check the complete electrical system to the compressor 

and  compressor  internal  electrical  system,  check  to  be 

certain that compressor is not out on internal overload. 

Complete evaluation of the system must be made whenever 

you suspect the compressor is defective. If the compressor 

has been operating for sometime, a careful

 examination 

must be made to determine why the compressor failed.  

Certain unit components operate at 

temperatures hot enough to cause burns.

Proper safety procedures must be followed, 

and proper protective clothing must be 

worn.

Failure to follow this warning could result 

in moderate to serious injury. 

With power off, remove the leads from compressor termi-

nals. If the compressor is hot, allow the overload to cool 

before starting check. Using an ohmmeter, test continu-

ity across the terminals of the external overload. If you 

do not have continuity; this indicates that the overload is 

open and must be replaced. 

The overload is embedded in the motor windings to 

sense the winding temperature and/or current draw. The 

overload is connected in series with the common motor 

terminal.

1. With no power to unit, remove the leads from the com-

pressor terminals. Allow motor to cool.

2. Using an ohmmeter, test continuity between terminals 

C-S and C-R. If no continuity, the compressor overload is 

open and the compressor must be replaced.