Jun 21, 2005 · The company I work for purchased one of these valves to install in one of our test units in our shop several years ago. After studying the valve, its operation, and the theory behind it, we installed and tested the valve under simulated loads. In and of itself, it worked “for the most part” as the manufacturer claimed.

Jan 22, 2015 · If you already have the Rawal valve just use it. So far as I can understand them all they are is an expansion chamber in the suction line into which HG is injected. Incorporated in with that is a desuperheating liquid injection valve into the same expansion chamber - to control compressor inlet temp under very low evap load.

Oct 12, 2015 · Anyone have any experience with the Rawal APR control in residential application? Have single stage AC w/WH dehum. Dehum runs almost 24/7. Prefer to have AC perform as a decent 2 stage, which this controller does.

Mar 25, 2012 · From speaking with Al B. the regional sales engineer for rawal, they accomplish increased run times by limiting the evap temperature. Reply 03-26-2012, 10:06 PM #19

Apr 6, 2017 · The Rawal valve would also use more energy to do less work, since the back pressure will be higher. Besides that, because the hot gas is not being piped into the evaporator inlet, I would be concerned with oil return to the compressor over extended run time - such as several months of shoulder seasons. Sent from my SCH-I545 using Tapatalk

Jun 2, 2017 · A Rawal valve on first stage and a dehumidistat to energize first stage on a rise in RH past set point along with constant fan would be my choice. On a drop in dry bulb under setpoint I would energize a stage or two of electric reheat.

Jun 14, 2021 · An idea that might be applicable is the Rawal Devices APR control. Google it. It is a combination HGBP and Desuperheating txv with a mixing chamber made for just such an application. A handy retrofit.

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TEST mode and open the Rawal valve. n) Allow system to stabilize and check sub cooling again. o) Add/Remove refrigerant as necessary to maintain about 4 degree of sub cooling. p) Remove gauges and replace service port covers. q) If charging for the fi rst time note all required conditions in startup sheets and record weight of all refrigerant ...

Aug 30, 2016 · This can be accomplished with either a scroll compressor with a slide plate on the scroll plate, a scroll compressor with a hot gas unloader (causes scroll plates to separate and stop refrigerant from pumping), an inverter driven compressor that has analog variable speed (not staged) to keep coil temperature above freezing, or a Rawal valve for ...