Tip: Read and understand the manufacturer's instructions
that accompany the humidifier Safety Tips: Before installing a humidifier turn off the furnace as well as the electrical power to it.
Installing a Humidifier
1) Mark the Placement of the Humidifier
In a typical installation, you tape a paper template for the humidifier on the
warm air plenum above the furnace. Use a level to make sure the lines of the template are level. Also mark the position of the humidifier duct on the
cold air return if needed. Then, using metal
cutting snips cut through the template and sheet metal along the lines of the template. To protect yourself, wear work gloves and safety
2) Install the Humidifier
Position the humidifier in the warm air plenum, making sure it is level. It's important to level the humidifier for even water distribution;
Then fasten the humidifier in place, following the manufacturer's instructions.
3) Cut Hole for
bypass Duct (if a bypass type)
Using metal snips, cut through the cold air return to make a hole for the humidifier
. some kit's comes with a mounting collar for the bypass.
4) Connect Duct (if a
Using flexible duct or a length of standard metal duct and an elbow fitting, connect the humidifier to the
cold air return.
5) Installing Water Supply to the Solenoid Valve
A typical humidifier has a solenoid valve to control water flow. This needs a small
1/4" flexible copper pipe or hard plastic tubing that runs from the saddle valve to the
6) Install a saddle valve
(if permitted by code)
on the hot water supply pipe. Clamp it to the
pipe, and turn the handle to pierce the pipe.
7) Provide for Overflow or drain
Whole house humidifiers typically have a catch basin that recirculates water, or
a 1/2" drain hose like this one.
8) Install the Humidistat
Following the instructions that accompany the humidifier, install the humidistat on the
cold air return or near the existing thermostat. A humidistat allows you to regulate the indoor humidity.
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Additional logos, brands, models, and product information are registered
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Copyright ©1999, 2000, Morrison Mechanical
Last modified: August 29, 2000