Air Handling System Monitor


Air Handling System Monitor
Air Flow/No Flow Switch
Air Flow Confirmation Switch
Low Air Flow Alarm Switch

Application Background:

Industrial and commercial HVAC systems are basically air handling systems that supply quality air for the buildings and facilities in which they are installed. Confirmation of the air flow throughout the system is important and vital to the efficient and effective delivery of the conditioned air be it cooled or heated.

Application Solution:

There are several air flow monitoring technologies including: paddle/flapper types and turbine vanes. All have proven to work with varying degrees of success. Some rely on operator’s time and attention, while some have mechanical parts and are prone to wear, hang-up, and fail.
A better solution for air flow detection at a specific point in a HVAC system is the Thermal Differential Switch. The TD switch has two thermal sensing devices (RTD’s) encased in stainless steel tips. One sensor detects the temperature of the ambient air while the second has a small current applied to create a thermal differential above the ambient air temperature. The differential temperature between a fluid flowing and not flowing is different. Therefore the detection of flow at the sensor probe is a simple, reliable technique for a point flow monitor.
With a single process connection into a HVAC duct or line either through a MNPT or flange fitting, a TD probe can be strategically located to monitor for flow of the air. When the probe detects the air flow, the TD switch activates a relay output to confirm that flow is occurring.
Any of the Delta M Corporation microtuf® and Versa-Switch® flow switch product models can provide the solution in this application. The microtuf® II flow switch is the most cost effective model for this application.

Air Handling System Monitor

For more details see Section 4.3 of the FS2100 manual to see how a set-point can be established for your specific application.

Recommended Products:

VERSA-SWITCH® – VS5100 Series Premium Mass Flow Switch
Dry Line Indication - Chemical Injection Monitor
Safety Relief Valve Monitor - Soot Blower Feed Water Monitor
Rotating Equipment Lubrication - Vapor Recovery Monitor
Gas Booster Monitor - Exhaust/Air Purge Monitor
  • User Selectable Power – 110/220VAC/24VDC
  • Optional Remote Electronics for easy setup
  • Nearly any Process Connection - Custom or Common
  • 2nd Channel for Detection of:
         Dry Lines, Temperature or Unit Diagnostics
  • Two year workmanship warranty