Refrigerant Migration in a Split-Unit Air Conditioner.
Refrigerant Migration in a Split-Unit Air Conditioner.
(5445 K)
Mulroy, W.; Didion, D.
No. 2868;
ASHRAE Transactions, Vol. 91, No. 1A, 193-206, January
1985.
Keywords:
refrigerants; air conditioning; valves; standards;
tests; degradation; test facilities; valves; equations
Abstract:
The relationship between cyclic refrigerant migration
and cyclic loss for a residential, split-system air
conditioner has been investigated. The cyclic
refrigerant migration was measured at different points
in the
operating cycle by simultaneously shutting five
pneumatically operated valves that isolated the
refrigerant in the
major system components. The refrigerant was then
removed, weighed, and returned to the system. The unit
tested was found to have a high initial increasing
capacity as trapped refrigerant was returned to the
system
fmm the accumulator. The unit performance was also
compared to single and double time constant regressive
approximations and to the time constant calculated from
the evaporator mass and heat transfer coefficient.
Although relationships between migrated refrigerant and
cyclic capacity were observed, no practical refrigerant
migration test method that would be less burdensome than
the cyclic tests of ASHRAE Standard 116 appears
possible at this time.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899