Honeywell MP904A5047 Product Description

The MP904A5047 is a modulating spring‑return pneumatic damper operator with integrated positioner manufactured by Honeywell. It converts 3‑10 psi proportional pneumatic control signal into precise linear mechanical stroke output to regulate air dampers and ventilation valves. Built with cast‑aluminum housing and rolling neoprene diaphragm, this actuator delivers 90 mm full stroke and high peak thrust force. The built‑in positive positioner continuously compensates load‑caused position drift, maintaining accurate damper position under variable duct static‑pressure. Widely deployed in commercial HVAC, boiler combustion air control and industrial ventilation systems, this legacy actuator is now end‑of‑life and mainly used as maintenance spare‑part for existing installations.

Product Features

• Integrated modulating positioner, eliminates positioning deviation induced by changing damper load and duct pressure
• Spring‑return fail‑safe design, returns damper to preset safety position upon loss of air supply pressure
• 90 mm adjustable linear stroke, stroke travel can be mechanically limited via field‑installed stop nuts
• 3‑10 psi standard input signal range, adjustable signal start‑point for on‑site system matching
• High peak output thrust force, suitable for large‑size and high‑torque air dampers
• 1/4‑inch barbed air fitting for polyethylene tubing connection, simple pneumatic‑loop wiring
• Dual mounting configurations: internal Moduflow duct‑mount or external shaft‑bracket installation
• Wide working temperature range ‑30 °C ~ +70 °C, robust diaphragm construction for long‑term HVAC cyclic operation
• Obsolete original model; functional replacement series: Honeywell MP918A series actuators

Application Scenarios

• Commercial building HVAC air‑handling unit supply‑air and return‑air damper modulation control
• Boiler and furnace combustion‑air dampers for fuel‑air ratio regulation
• Industrial factory ventilation and exhaust‑gas system damper positioning
• Multi‑zone building pressure control and fresh‑air intake volume adjustment
• Retrofit spare‑part replacement for legacy Honeywell pneumatic HVAC control systems
• Process plant auxiliary ventilation and air‑flow regulation loops
• Central air‑conditioning plant pneumatic sequence‑controlled multi‑damper coordination projects

Frequently Asked Questions