Honeywell C7400 User Manual

SYSTEM ENGINEERING GUIDE
63-2484—03
Solid State Economizer System
(CONSISTING OF: C7046C DISCHARGE AIR SENSOR OR C7150B MIXED AIR SENSOR, C7400 SOLID STATE ENTHALPY
SENSOR OR C7660 SOLID STATE TEMPERATURE SENSOR, M7415, M7215 OR M8405 DAMPER ACTUATORS OR MODU-
LATING DIRECT COUPLED ACTUATORS (MS7503 or MS7505) T6031H THERMOSTAT AND W7459 OR W7212 SOLID
STATE ECONOMIZER LOGIC MODULE)
APPLICATION
The Solid State Economizer System provides an economical
method of providing cooling air by incorporating outdoor air in
the first stage of cooling in heating, ventilating and air
conditioning (HVAC) systems. The Solid State Economizer
System consists of the C7046C Discharge Air Sensor or
C7150B Mixed Air Sensor, C7400 Solid State Enthalpy
Sensor or C7660 Solid State Temperature Sensor, M7215,
M7415 or M8405 Damper Actuators or Modulating Direct
Coupled Actuators (MS7503 or MS7505), T6031H Thermostat
and W7212A,C or W7459A,C Solid State Economizer Logic
Module.
FEATURES
C7046C Discharge Air Sensors have probe lengths of 8 in.
(203 mm) and nominal sensor resistance of 3000 ohms at
77°F (25°C).
• No setting or calibration required.
• Solid state components not affected by dust or dirt.
• Fast reacting.
• Rugged aluminum insertion probe.
C7150B Mixed Air Sensor is used with the W7212/W7459
Economizer Module to sense mixed or discharged air in roof-
top packaged air conditioning equipment.
• No setting or calibration required.
C7400 Solid State Enthalpy Sensor and C7660 Solid State
Temperature Sensors are used with the W7212/W7459 Solid
State Economizer Logic Module to sense outdoor and return
air enthalpy or temperature.
• C7400 senses and combines temperature and humidity
(enthalpy) of outdoor air (heat index).
• C7660 senses temperature only and can only be used
in single referential control. Use C7400 enthalpy for
differential control.
• When enthalpy/temperature of outdoor air increases,
the outdoor air damper closes to a preset minimum
position.
• When enthalpy/temperature of outdoor air is low, the
outdoor air damper opens to reduce the building
cooling load.
C7150B
M7215/M7415/
M8405
C7046C
W7459A,C
C7400A/C7660
W7212A,C
T6031H

Honeywell C7400 Specifications

General

Brand	Honeywell
Model	C7400
Category	Control Systems
Language	English

Summary

Introduction to the Solid State Economizer System

System Features

Details the capabilities and benefits of the Solid State Economizer System components.

System Application

Describes the use of the Solid State Economizer System in HVAC applications.

Economizer System Components

Damper Actuators

Details M7415, M8405, MS7503, MS7505 actuators for economizer control.

Logic Modules and Thermostats

Introduces W7459, W7212 logic modules and T6031H thermostat.

Component Specifications

Discharge and Mixed Air Sensors

Specifications for C7046 Discharge Air and C7150B Mixed Air Sensors.

Enthalpy and Temperature Sensors

Specifications for C7400 Enthalpy and C7660 Temperature Sensors.

Actuator, Thermostat, and Logic Module Specifications

Damper Actuator Specifications

Provides specifications for M7415 and M8405 damper actuators.

Logic Module Specifications

Details specifications for W7459 and W7212 economizer logic modules.

Installation Procedures

Actuator and Sensor Installation

Guidelines for installing actuators and the C7046C discharge air sensor.

Logic Module Mounting

Instructions for mounting W7459 and W7212 economizer logic modules.

Settings and Operation

System Settings and Adjustments

Covers minimum damper position and enthalpy setpoint adjustments.

Economizer Sequence of Operation

Describes how the economizer operates under various conditions.

Troubleshooting and Checkout

Economizer Troubleshooting Guide

Provides steps for diagnosing and checking economizer system issues.

Checkout Procedures

Details the steps for checking the W7212, W7213, W7214 economizers.