Applications
Specialty Applications
Some of the toughest jobs in DX are not about comfort, they are about holding a critical condition. When the space cannot tolerate a swing in temperature or humidity, or the equipment has to run reliably at very low load, standard on/off staging runs out of room. This is where Rawal Devices variable capacity does its most demanding work.
How to read this page
Depending on how precise the discharge-air control must be, the fix is either the mechanical APR Control or the electronic APR‑E Valve, and a Rawal Devices Engineer helps pick the right one.
Where it matters most
Critical Environments
Cleanrooms
The APR‑E Valve held discharge air to about ±1°F across ISO Class 8 to Class 1 cleanrooms in an ASHRAE research project on a single-stage unit.
Laboratories
Laser and optical labs where temperature and humidity swings disrupt alignment (APR Control on 2-ton 100% outside-air units ran 15+ years and survived an R-22 to R-407C conversion), and test labs (a 3-ton unit pulled from over 80% RH down to 47 to 53% RH).
Medical Imaging & Radiology
MRI and PET-CT rooms swing from full load to idle, the APR Control holds roughly 68 to 72°F and 48 to 52% RH in compliance-critical spaces.
Pharmaceutical Manufacturing
Within required ranges for regulated environments on 100% outside air, a retrofit dropped RH from 65% to 45% at 68°F in about a day.
Cold Storage & Low-Temp
Where standard DX risks coil freeze-up at low load, the APR Control holds suction pressure to keep the coil above freezing, valued for immediate availability.
Indoor Agriculture & Grow Rooms
Rapidly shifting sensible and latent ratios over light cycles, the APR Control modulates to the load and the APR‑E Valve controls discharge dewpoint for VPD, reducing reheat and humidifier load.
Surgical Suites & Hospitals
Tight temperature and humidity for operating-room environments.
High Air-Changes Environments
Labs, compounding pharmacies, and imaging suites needing 15 to 30+ air changes per hour.
Broadcast & Newsrooms
Quiet operation under variable single-zone loads.
Beyond this list
Doing Something Unusual?
The environments above are the ones we can point to with published results, but they are far from the full range. If your load profile is odd, your tolerances are tight, or you have been told it cannot be done on standard DX, that is exactly the conversation we want to have.
Tell a Rawal Devices Engineer what you are trying to hold and on what equipment. If a mechanical APR Control or an electronic APR‑E Valve can do the job, we will size it to your application through a complimentary engineering consultation, and if it cannot, we will tell you that too.
Get Expert Help
Complimentary application sizing, matched to the right valve, with a one-business-day response.
Talk to an Engineer[email protected] · 800‑727‑6447 · rawal.com