The Castair RS114 is a 1-1/4" NPT standard regulator rated at 250 maximum PSI and 400 CFM, sold without a gauge (*). The RS114 sits one step below the RS112 in the Castair regulator lineup — a 1-1/4" body handling 400 CFM, rated to 250 PSI inlet. This is a main-header regulator for medium to large industrial air supply systems. It is appropriate where you need high-flow pressure regulation without the full 1-1/2" pipe sizing that the RS112 requires.
Application and Sizing Context
The RS114 fits installations where:
- 1-1/4" header piping: Your supply header is 1-1/4" and you need pressure regulation at the main header before branching to drop legs and individual stations
- 400 CFM demand: Your aggregate downstream demand falls in the range serviced by 15–30 HP compressors or smaller duplex installations — the RS114's 400 CFM capacity matches without over-sizing
- 250 PSI system: Full-system-pressure rated — safe to install directly on a high-pressure header without being the weakest component in the line
- No-gauge preferred: Monitoring is done downstream, or a gauge will be added separately to the gauge port on this unit
Castair Regulator Lineup — Where RS114 Fits
- C-RS12 — 1/2" Std, 250 PSI, 104 CFM — individual station or small drop leg
- C-RS34 — 3/4" Std, 250 PSI, 162 CFM — small header or high-demand station
- C-RS10 — 1" Std, 250 PSI, 162 CFM — medium header
- RS114 (*) — this unit — 1-1/4" Std, 250 PSI, 400 CFM — medium to large header, no gauge
- RS112 (*) — 1-1/2" Std, 250 PSI, 500 CFM — large main header, no gauge
The filter/regulator combination units (C-FRS12, C-FRS34, etc.) include a 5-micron filter and gauge — appropriate for individual stations. The RS114 and RS112 are regulators only, for main-line header applications where filtration is handled upstream.
Installation Recommendation
Install an upstream 5-micron particulate filter (FS114 for 1-1/4" lines, or FS112 for 1-1/2") before this regulator in any installation where pipe scale, rust, or debris could enter from the tank side. Debris on the regulator poppet seat causes pressure creep and regulator failure. A good upstream filter protects the regulator investment.
Technical Specifications
- Part Number: RS114* (no-gauge configuration)
- Inlet/Outlet Size: 1-1/4" NPT
- Maximum Inlet Pressure: 250 PSI
- Flow Rating: 400 CFM
- Gauge: Not included (gauge port present for field installation)
- Category: Air Drying Equipment — Filters/Regulators
- Manufacturer: Cast Air
Why Buy From OEM Diagnostic Tools?
Castair air system regulators and filtration components stocked and shipped from our warehouse. Free shipping on qualifying orders. Free tech support at 866-217-0063. Full Castair manufacturer warranty. Call us if you need help sizing regulators for your system layout.
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