AFS

Supported Applications

The ACI AFS Series Differential Pressure Switches are general-purpose proving switches designed for HVAC and Energy Management applications. These devices sense positive, negative, or differential air pressure to monitor filter blockage, prove flow conditions (excessive or insufficient), and trigger alarms or control actions.

• Monitoring Filter Blockage
• Proof of Flow
• Prove Excessive or Insufficient Air Flow/Pressure
• Alarms and Control Systems

Operating Conditions & Performance

The series operates within an ambient temperature range of -40 to 180°F (-40 to 82°C) and a humidity range of 10 to 95% RH, non-condensing. Maximum pressure ratings are specified at ½ psi (0.03 bar; 3.45 kPa). Measured media includes air or combustion by-products that will not degrade silicone.

Performance ranges vary by model:

• AFS-222: Input/Set Point Range of 0.05 +/- 0.02" to 12" wc; Field Adjustable "Operate" Range from 0.07 to 12.0" wc.
• AFS-262: Input/Set Point Range of 0.05 +/- 0.02" to 2.0" wc; Set Point Range starting at 0.07" to 2.0" wc.
• AFS-460: Input/Set Point Range of 0.40 +/- 0.06" to 12.0" wc; Field Adjustable "Operate" Range from 0.46" to 12" wc.

The approximate switching differential is progressive, increasing from 0.02 +/- 0.01" wc at the minimum set point to 0.8" wc at the maximum set point. Life expectancy exceeds 100,000 cycles for AFS-222/AFS-262 and 6,000 cycles for AFS-460 models.

Configuration Options

The series offers configurable contact arrangements, reset styles, and process connections to meet specific installation needs. The enclosure is constructed of galvanized steel with a conduit opening accepting ½" conduit (7/8" diameter).

• Contact Arrangements: SPDT w/Automatic Reset (AFS-222/262), SPST-N/C w/Manual Reset (AFS-460), DPDP w/Manual Reset (AFS-460-137), and 2 SPST-NC Lead/Lag Manual Reset (AFS-460-DSS).
• Electrical Ratings: AFS-222/262 support 300 VA pilot duty @ 115 to 277 VAC, 60 Hz; 15A non-inductive to 277 VAC. AFS-460 supports 15A @ 125, 250, or 277 VAC / ½A @ 125 VDC, ¼A @ 250 VDC.
• Process Connections: Integral compression fitting accepting ¼" OD rigid or semi-rigid metallic tubing. The "-112 Option" includes two barbed fittings for ¼" flexible plastic tubing (Part# 18311).

Key Product Differences

The AFS Series is distinguished by model-specific pressure ranges and switching logic:

• AFS-222 & AFS-262: Feature SPDT contacts with automatic reset. The AFS-222 covers a broader range (0.05 to 12" wc) compared to the low-range AFS-262 (0.05 to 2.0" wc).
• AFS-460: Features SPST-N/C contacts with manual reset, requiring operator intervention upon actuation.
• AFS-460-DSS: A dual-switch variant offering 2 SPST-NC Lead/Lag (manual reset) for applications needing separate set points. The Lag Switch B Set Point is configured as a percentage after the Lead Switch A Set Point, ranging from up to 5% to up to 35% depending on the pressure range.
• AFS-460-137: Provides DPDT contacts with manual reset and an input range of 0.60 to 12.0" wc.