Nortec 0-10 V Wall & Duct Humidistat - Manual

2556314—D | 03 October 2014 Introduction | 1
0-10 V Wall & Duct Humidistat Installation Instructions
This document covers the operation and installation instructions for the following Nortec Digital Humidistats:
Part #:
Description:
1510142 0-10 V Digital Wall Humidistat
2520266* 0-10 V Digital Duct Humidistat
Note: Part #2520266 is comprised of two parts:
1509857
Duct Sensor
2520261 Humidistat w/o sensor
1510142 – 0-10 V Digital Wall Humidistat Installation
Location
1. The wall humidistat should not be installed on an outside wall.
2. The sensor should be installed away from any heat source and away from direct sunlight.
3. The wall surface should be flat and clean.
4. Any draft originating from the wall interior should be prevented from interacting with the humidity sensor. A vapor barrier should be
installed.
5. Nortec recommends using a sealed, single-gang electrical mounting box (recessed in wall) to mount the wall humidity sensor.
Installation
1. Pull cables 6” (15cm) out of the wall
2. To remove the front face with the digital display, loosen the retaining screw at the bottom of the case. Pull firmly but gently on the bottom
of the front face to unplug the face from the backboard. The front face will unhinge from the top retaining clips.
3. Connect the control wires to the terminals according to the wiring diagram(s). Table 1 outlines the terminal layout of the digital
humidistat.
4. Secure the metal bracket to the mounting box using 2 screws. Make sure the screw heads do not stand out more than 1/5” (5mm) from
the mounting surface.
5. Mount the front face onto the metal bracket. Ensure the top clips engage the grooves on the top of the metal bracket. Carefully lower the
front face until the interconnector reaches the mounting plate. Ensure the connector pins are aligned with the plug on the back plate.
While inserting the connectors, a slight resistance will be felt. Continue pressing gently until the front face is fully seated and tighten the
retaining screw to secure the face.
2520266 – 0-10 V Digital Duct Humidistat Installation
Part #1509857 – Duct Sensor Installation
Location
1. The duct sensor should be installed directly on the duct in an area where the air is well mixed with uniform flow.
2. The supply air sensor should be mounted downstream of the steam distributor at a distance 1.5 times the absorption distance (typically
10-12 ft or 3-3.7 m).
3. If a return air humidity sensor is used it should be mounted close to the air inlet but downstream from a return fan if one is present.
Installation
1. Open the housing by removing the 4 screws securing the housing together.
2. Push the probe through the center hole and tighten the 2 mounting screws.
3. Drill a 1/2” (13mm) hole in the duct and insert the probe into the air stream.
4. Secure the sensor to the duct using 2 sheet-metal screws.
5. Connect the signal wires to the sensor terminal strip. Table 1 outlines the terminal layout of the digital humidistat.
6. Connect the plug from the temperature probe to the PCB board into the plug marked ‘PROBE’.
7. Close the cover and secure using the 4 Screws removed in step 1.
Part #2520261 – Humidistat w/o Sensor Installation
Refer to the installation instructions on page 1 for Part #1510142 – Wall Humidistat Installation.
Table 1: Humidistat Terminal Layout
Wall Humidistat - (Part # 1510142) Humidistat w/o Sensor - (Part # 2520261)
Ground 1 1
24 VAC 2 2
Outdoor Temperature Input 8 8
Control Output 6 6
Duct Sensor Input N/A 7