Cleveland Controls · Division of UniControl Inc. · Cleveland, Ohio since 1942

Cleveland Controls Air Pressure Switches —
NS2, AFS, FS-751, RFS & Specialty Series

Memphis Control Center stocks and special-orders Cleveland Controls air pressure sensing switches for commercial and industrial HVAC, combustion air proving, duct heater, energy management, food service, and hazardous location applications. NS2 Series — OEM fixed set-point and field-adjustable kit switches for residential and light commercial HVAC (induced draft fan and combustion air proving on furnaces and boilers). AFS Series — field-adjustable switches for commercial HVAC and energy management (0.05"–12.0" W.C., NEMA-1 through NEMA-7/9 hazardous location models). FS-751 Series — fixed, nonadjustable switches with conduit enclosure for duct heaters and ovens. RFS Series — OEM replacement furnace switches. All switches sense positive, negative, or differential air pressure and are rated for air and byproducts of combustion. Cleveland Controls is a division of UniControl Inc., manufacturing at 1111 Brookpark Road, Cleveland, Ohio 44109 since 1942. 366 products — most are special order. Call (901) 458-2000 for availability and lead times.

Division of UniControl Inc. Cleveland, Ohio since 1942 UL · CUL · CSA · CE · Aust. Gas Assoc. 366 Products · Special Order
OEM & Aftermarket CoverageNS2 fixed set-point switches are specified OEM by furnace and boiler manufacturers — match by exact part number for compliant replacement
Made in Cleveland Since 1942Cleveland Controls has manufactured at 1111 Brookpark Road, Cleveland, Ohio for over 80 years as a division of UniControl Inc.
Positive · Negative · DifferentialAll Cleveland Controls switches sense positive, negative, or differential air pressure — configured by which ports the sample lines connect to
Application Help AvailableCross-reference your existing part number or set point — call (901) 458-2000. We've been sourcing Cleveland Controls switches since 1967
⚠ Special Order — Call for Availability: Most Cleveland Controls products at Memphis Control Center are special order with variable lead times. Call (901) 458-2000 or contact us before ordering to confirm availability and estimated ship date. Have your existing part number or OEM equipment model number ready — do not order by set point alone, as the same set point may be available in multiple configurations.

Cleveland Controls — Series Guide

Cleveland Controls manufactures multiple switch series, each for specific application requirements. All series sense positive, negative, or differential air pressure via a diaphragm and snap-acting switch. Sample medium: air and byproducts of combustion that will not degrade silicone or polycarbonate. Contact us to cross-reference a part number.

NS2 Series NS2 — OEM Fixed Set-Point & Field-Adjustable Kits

The Cleveland Controls NS2 Series is a compact, economical family of air pressure sensing switches for residential and light commercial HVAC applications. The most common application is induced draft fan proving and combustion air proving on gas furnaces and boilers — the switch verifies the draft inducer is running before ignition is allowed to proceed. Two variants:

NS2 with fixed set-point (e.g. NS2-1018-00, NS2-0461-00, NS2-1166-00): Factory-calibrated at a specific set point. Part numbers ending in a non-zero suffix (NS2-XXXX-00, -01, etc.) are typically OEM-specified fixed set-point models. The set point is not readable directly from the part number digits — always match the complete part number or verify against the Cleveland Controls datasheet or your equipment's service manual.

NS2-0000-xx field-adjustable kits (e.g. NS2-0000-00, NS2-0000-01, NS2-0000-03): Field-adjustable range of 0.10"–10.0" W.C. Includes springs, orifice restrictors, and brackets. Used when an exact OEM fixed switch is unavailable or when a field-configurable replacement is needed.

Construction (both variants): Glass-filled polycarbonate housing, post-cured silicone diaphragm, integral SPDT snap-acting switch, three 90° male quick-connect terminals. Color-coded ports: high pressure = black, low pressure = gray. Operating range: 0.05"–10.0" W.C. Max pressure: 14" W.C. Operating temperature: −40°F to 190°F (−40°C to 88°C). Product life: 100,000 cycles minimum. Approvals: UL, CUL, CSA, CE, Australian Gas Association.

Fixed Set-Point (OEM) or Adjustable Kit 0.05"–10.0" W.C. Range SPDT · SPST Options Glass-Filled Polycarbonate −40°F to 190°F 100,000 Cycles Min. UL · CUL · CSA · CE Fan Proving · Combustion Air
AFS Series AFS — Field-Adjustable Air Pressure Switches

The Cleveland Controls AFS Series are general-purpose field-adjustable air pressure proving switches for commercial HVAC, energy management, food service, and industrial applications. Unlike NS2 fixed set-point switches, AFS switches allow the set point to be configured in the field. Set point range: 0.05"–12.0" W.C. (varies by model). Senses positive, negative, or differential air pressure.

SPDT snap-acting switch. 300 VA pilot duty (higher than NS2's 125 VA). 120–277 VAC. Housing styles range from basic open-mount (AFS-222, AFS-227, AFS-275) to NEMA-7/9 explosion-proof (AFS-952, for Class I hazardous locations). AFS-460 includes a manual reset requiring operator intervention after actuation. Applications: package burners, duct heaters, furnaces, fuel-burning equipment, kitchen exhaust, pool and spa heaters, building energy management.

Models on your site: AFS-275-206 (adjustable SPDT), AFS-952-2 (NEMA-7/9 hazardous location, 0.05"–12.0" W.C., 300 VA, 120–277 VAC).

Field-Adjustable 0.05"–12.0" W.C. SPDT · 300 VA Pilot Duty 120–277 VAC NEMA-1 / -5 / -7 / -9 Options Commercial HVAC · Energy Mgmt Food Service · Industrial
FS-751 Series FS-751 — Fixed Nonadjustable with Conduit Enclosure

The Cleveland Controls FS-751 Series is a fixed set-point (nonadjustable) airflow proving switch in a conduit enclosure — used in duct heater, oven, and HVAC applications requiring physical protection and a non-adjustable switch. Standard set point: 0.05" W.C. SPDT.

Variants on your site: FS-751 (with compression fitting), FS-751-112 (with covered switch), FS-751-337 (SPDT with delay timer), FS-751-339 (SPST with delay timer), FS-751-385 (Arrow Flow replacement model), FS-BO-178 (TUTCO replacement model). The 21123-112 is an 8" sensing probe with barb end — a replacement accessory compatible with FS series switches.

Fixed · Nonadjustable 0.05" W.C. Standard Conduit Enclosure Duct Heater · Oven · HVAC Delay Timer Variants TUTCO · Arrow Flow Replacements
RFS · DDP · DFS · DFSL/H Specialty Series — Replacement, Differential & Fixed

RFS-4100 (Replacement Furnace Switches): OEM replacement switches for specific residential and commercial furnace models. Match by original equipment part number — do not substitute by set point alone.

DDP-106 (Differential Pressure Switches): Adjustable differential air pressure sensing switch. SPDT. Used for filter monitoring, duct static pressure control, and fan proving in commercial HVAC. Models DDP-106-200 and DDP-106-112 on your site.

DFS-448 (Fixed Airflow Switch): Fixed set-point, positive pressure sensing. DFS-448-153 on your site — used in commercial HVAC fan proving where only positive pressure sensing is required.

DFSL-CO / DFSH-CO (Fixed with Enclosure Box): Fixed set-point SPDT switches with an included enclosure box ("CO" suffix). DFSL-CO = 0.2" W.C.; DFSH-CO = 0.4" W.C.

RFS = OEM Replacement Furnace DDP = Differential · Adjustable DFS = Fixed · Positive Only DFSL = 0.2" W.C. · DFSH = 0.4" W.C. CO = With Enclosure Box

Series Selection — Which Switch Do I Need?

Use this table to narrow down the correct series. Always match the complete part number for OEM replacements — set point alone is not sufficient. Contact us or call (901) 458-2000 to cross-reference.

SeriesSet Point RangeAdjustable?ContactsElectricalPrimary Application
NS2 (fixed)0.05"–10.0" W.C. (factory set)No — OEM fixedSPDT / SPST28–125 VA · 24–277 VACResidential / light commercial furnace & boiler fan proving; OEM-specified
NS2-0000-xx (kit)0.10"–10.0" W.C.Yes — field adj.SPDT28–125 VA · 24–277 VACField-configurable replacement for residential / light commercial HVAC
AFS (standard)0.05"–12.0" W.C.Yes — field adj.SPDT300 VA · 120–277 VACCommercial HVAC, energy management, package burners, duct heaters, food service
AFS-9520.05"–12.0" W.C.Yes — field adj.SPDT300 VA · 120–277 VACHazardous locations — NEMA-7/9 explosion-proof
FS-7510.05" W.C. (fixed)No — fixedSPDT / SPSTVaries by modelDuct heaters, ovens — conduit enclosure; delay timer variants available
RFS-4100OEM-specifiedNo — OEM fixedSPDTVariesDirect replacement for specific residential / commercial furnace models
DDP-106Adjustable (model-specific)Yes — field adj.SPDTVariesDifferential pressure — filter monitoring, duct static, fan proving
DFS-448Fixed (model-specific)No — fixedSPDTVariesPositive-pressure airflow proving only
DFSL-CO0.2" W.C. (fixed)No — fixedSPDTVariesFixed set-point with enclosure box
DFSH-CO0.4" W.C. (fixed)No — fixedSPDTVariesFixed set-point with enclosure box
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Need to cross-reference a Cleveland Controls switch?

Have your complete part number or OEM equipment model number ready — we'll find the right switch and check availability.

Cleveland Controls — Frequently Asked Questions

Common questions on selecting, cross-referencing, and replacing Cleveland Controls air pressure switches. Contact us or call (901) 458-2000.

How do I find the correct replacement for a Cleveland Controls NS2 pressure switch?

Match the complete part number exactly — for example NS2-1018-00 or NS2-0461-00. The digits in an NS2 part number are an internal model code; they do not directly encode the set point as a readable decimal value, so don't try to calculate the set point from the number. Look up the set point on the Cleveland Controls NS2 datasheet (available at clevelandcontrols.com), on your switch label, or in your equipment's service manual. If you only have the furnace or boiler make and model, call us at (901) 458-2000 and we can help identify the correct switch.

What is the difference between NS2, AFS, and FS-751 series?

NS2: Compact OEM-specified switches for residential and light commercial HVAC — primarily induced draft fan proving. Available as factory-fixed set-point models and field-adjustable kits (NS2-0000-xx). Fixed models must be replaced with the identical part number for OEM compliance. AFS: Field-adjustable (0.05"–12.0" W.C.) for commercial HVAC, energy management, food service, and industrial applications. Higher pilot duty (300 VA) than NS2. AFS-952 is NEMA-7/9 rated for hazardous locations. FS-751: Fixed, nonadjustable switches in a conduit enclosure — for duct heaters, ovens, and applications requiring physical protection. Delay timer variants available.

What does an air pressure switch do in a furnace or boiler?

It is a safety interlock that proves the draft inducer motor is running before the ignition sequence begins. The inducer creates a negative pressure (vacuum) in the flue pathway. When that vacuum reaches the switch's set point, the switch closes and tells the control board it is safe to open the gas valve and fire the igniter. If the inducer is not running — failed motor, blocked flue, bad capacitor, frozen condensate drain — the switch stays open and the furnace won't fire. This prevents unsafe combustion conditions and carbon monoxide production. Always replace with the exact OEM part number.

Can I replace a fixed NS2 switch with an adjustable kit or AFS switch?

An adjustable NS2-0000 kit or AFS switch can be set to the same trip point — but OEM manufacturers specify fixed switches because the set point cannot be accidentally changed in the field. An adjustable switch substituted in a combustion air proving circuit creates a risk of later tampering that would defeat the safety interlock. For code-compliant and warranty-compliant replacements, use the exact NS2 part number. If that part is discontinued or unavailable, contact us and we can help identify approved alternatives.

Who makes Cleveland Controls switches and where are they manufactured?

Cleveland Controls is a division of UniControl Inc., manufacturing at 1111 Brookpark Road, Cleveland, Ohio 44109 — (216) 398-0330 — clevelandcontrols.com. Founded in 1942 by Norman Hahn as Cleveland Fuel Equipment Company, renamed Cleveland Controls, Inc. in 1958, and reorganized as a UniControl Inc. division in 1994. The air pressure switch product lines continue under the Cleveland Controls brand. Memphis Control Center has been sourcing Cleveland Controls switches since 1967.

For emergencies, outside of business hours, call #901-604-7069