Chapter - 121,122 Flashcards
What are the inert gases?
Dry nitrogen
Carbon dioxide
Argon
When refrigerants that contain chlorine are burned what is produced
Phosgene gas
What are two ways ammonia leaks can be detected
Litmus paper and sulphur candle
Where is the initial refrigerant added to the system
The high-pressure side
Where do noncondensible gases collect
In the condenser
Why is higher than normal head pressure undesirable
Because it increases power consumption and adds stress to the system
How are noncondensible gases removed from the system
By manual or automatic purging
What can cause a high discharge pressure in a refrigeration system
An overcharge system and noncondensible gases
What is the primary function of a chilling coil in an automatic purger
To separate refrigerant vapour from the noncondensible gases
What are two devices used to detect leaks in a Freon system
Halide torch and electronic leak detector
What is the reason for opening the bypass valve when starting the compressor?
So the compressor is started in an unloaded state
