Huba Control 605.99E42 Combi Boiler Air Pressure Switch (Horizontal 52/42 Pa - Vertical 62/52 Pa)

This is one of the most critical safety components of the system (air flow switch), monitoring whether flue gas is properly expelled by the fan in room-sealed combi boilers. Manufactured to the quality of Huba Control, one of the industry's leading manufacturers, this original spare part reliably solves the common field faults "the fan runs but the combi boiler does not go to ignition" or "no spark".

Key Technical Specifications and OEM Values

• Brand and Model: Huba Control / 605.99E42 (Alternative Code: 6225734 - CVXAHD)
• Operating Pressure Values (Depending on Mounting Orientation): The sensitivity of this model changes with gravity. According to the label values, it switches at 52/42 Pa in Horizontal (Orizzontale) mounting and at 62/52 Pa in Vertical (Verticale) mounting.
• Electrical Rating: 1(0.5)A / 250V AC. Its standard micro-switch design sends a stable, lossless dry-contact signal to the electronic board.
• Connection Design: It has 2 pin (faston) terminals resistant to condensation and oxidation, and standard silicone hose inlets (P1, P2).

Technician Tips and Installation Warnings in the Field

• Watch the Mounting Orientation: When fitting the new air pressure switch, keep exactly to the orientation (horizontal or vertical) of the old part inside the combi boiler. Otherwise the diaphragm inside will respond at the wrong pressure value (such as 62 instead of 52 Pa) and the appliance will go to fault again.
• Before replacing the pressure switch, always check inside the pitot tube (venturi) at the fan motor outlet and the silicone hoses leading to the pressure switch. Accumulated soot or dust, or even the slightest melting/hole in a hose, will prevent your newly fitted pressure switch from reading the pressure.
• When fitting the terminals (spade connectors), check for oxidation; poor contacts prevent the pressure switch signal from reaching the board.