Vogt P-24AL, Руководство по обслуживанию

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P24AL & P34AL Service Manual
SERVICING OPERATIONS
12/2016
9-18

Apply soap solutions with a narrow brush or spray bottle to all joints, welds, or areas of
suspicion. The solution will form bubbles if there is a leak.

Sulfur sticks and test paper can be obtained from your ammonia supplier.

Light the end of the sulfur stick and pass it around suspected points of leakage. A white cloud
will form where a leak is, even if it is very small.

Moisten a strip of test paper and pass it around the suspected area. If the paper comes in contact
with ammonia, it will turn red. Coils submerged in water, or condenser cooling water may be
tested by dipping a strip directly in the water. If ammonia is present, the paper will turn red.
Always remove refrigerant pressure from the vessel, tubing, or component part before repairs are
attempted.
Non-condensable Gasses. Satisfactory operation of the machine is not possible if non-condensable
gases (usually air) are present in the system. Excessive condensing pressure is an indication of such
gases. Excessive condensing pressure in water-cooled condensers may also be due to the
accumulation of scale in the cooling coil or due to insufficient cooling water or excessive water
temperature. See Chapter 7 “Water-Cooled Condensers”, and Chapter 9 “Condenser Cleaning”.
Purging Non-Condensables . Air and other non-condensable gases in a refrigeration system are not
desirable. Purging air from your Tube-Ice machine will greatly improve system performance and
save money.
Non-condensable gas effects are:
1.
Higher condensing pressure than what should match the condensed liquid temperature.
2. Greater electrical power consumption.
3. Reduced refrigeration capacity.
4. Longer than normal compressor running time.
5. Slow ice release and long thaw cycle.
Air collects mostly in high pressure condensers, receivers, and other high-pressure components. It is
most commonly found in the coolest, lowest-velocity area of these components.
Evaporative condensers usually have purge points at the top of the outlet header of each circuit.
Receivers usually have a purge point at the top, away from the inlet, where it is coolest and the gas
velocity is the lowest.
The freezer can be purged through the valve at the top of the suction accumulator, but should be
done only during the thaw cycle or after the system has been idle at least two hours.