Archive for the ‘Refrigeration Notes’ Category

January 11, 2013

Evaporator: liquid to a gas…. cold line…absorbing heat
Compressor: vapour back to a liquid….hot line giving off heat

Azeotrope & Fractional Hermetric Sealed Compressor

September 24, 2010

It’s common to carry at least 6 different refrigerants in the van.

These are called “Azeotropes”.

What is Hermetically Sealed Compressor?

In hermetically sealed compressor, the compressor and the motor are enclosed in the welded steel casing and the two are connected by a common shaft. This makes the whole compressor and the motor a single compact and portable unit that can be handled easily. The hermetically sealed compressor is very different from the traditional open type of compressors in which the compressor and the motor are different entities and the compressor is connected to the motor by coupling or belt.

Nitrogen Purge

March 10, 2010

Nitrogen is used to purge and dry the lines of any moisture after welding etc. This moisture can’t be condensed in the system. Moisture carrodes the motor windings and breaks down the oil in the motors.

Atmosphere pressure is 14.7

Water Cooled Refrigeration Systems

January 17, 2010

When water supply is turned off the compressor runs, builds up heat and head pressure.(Which is basicaly the same thing). Head pressure is normaly at aprox 150. At 300 manual head pressure sensors are tripped and the compressor will not run. Automatic reset head pressure sensors will cycle on and off continuously until water is restored. Cooling will not be effective during cycling.
If water is turned off to a building you must turn refrigeration off too!

TX Throttles amount of refrigeration to control super heat