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Refrigeration
Suction Accumulators
QUESTION:
Can two suction accumulators be compared or cross-referenced by nipple size
and external dimensions only?
ANSWER:
NOT AT ALL! - Internal design can be of even greater importance!!
After a compressor slugs, oil must be returned to the crankcase at a fast enough rate to prevent bearing damage,
and at the same time liquid refrigerant must be metered back slowly enough to prevent valve or other compressor
damage. Therefore, orifice and internal tube design is very important and there must be a sufficient number of
model choices for EXACT SELECTION.
1. Liquid flood back can break valves, pistons, and damage compressors severely. However, a PROPERLY
DESIGNED inlet deflector can increase EFFECTIVE HOLDING CAPACITY by as much as 20%, thereby
decreasing flood back. Some manufacturers do not provide inlet deflectors at all!
2. To maintain compressor capacity, pressure drop through the accumulator must be at a minimum. Therefore, the
evaporator temperature (a measure of load) must be considered along with the capacity of the condensing unit.
See Application Tables for correct sizing information.
3. But to accomplish the above, proper internal design and a sufficient number of model choices must be available.
Refrigeration Research offers over 50 models for EXACT SELECTION. - TO FORCE A SQUARE PEG INTO
A ROUND HOLE CAN BE VERY COSTLY. - Don’t take a chance. Use only suction accumulators made by
REFRIGERATION RESEARCH.
SELECTION OF A SUCTION ACCUMULATOR:
The suction accumulator should not necessarily be selected to have the same size inlet and outlet as the
compressor suction line. It is more important to select the suction accumulator well within the limits of (1) pressure
drop and (2) oil return as shown on the following page. Total amount of charge to be held (3) is also important.
The actual refrigerant holding capacity needed for a suction accumulator is governed by the requirements of the
particular application. There is a great variation in refrigeration systems and this must be considered. Where
possible, the capacity selected should be checked by actual test. Normally the accumulator should not be sized
for less than 50% of the total system capacity. If in doubt, consult the compressor manufacturer. Steel nipples are
available on special order.
THE LARGEST SELECTION OF
SUCTION ACCUMULATORS IN
THE INDUSTRY!
Suction Accumulators
