Model IGX Make-Up Air
42
®
For complete furnace information reference the Indirect Gas-Fired Heat Modules IOM. Available turndown control
options include:
Electronic Modulation
Single Furnace
Unit
4:1- uses modulating valve and furnace
controller
*High turndown uses a 4:1 modulating
valve with a proprietary manifold and
furnace controller
Two Furnace
Unit
8:1- uses one 4:1 modulating furnace with
furnace controller and one 2-stage furnace
4:1 - uses two 4:1 modulating furnaces
controlled in parallel
*High turndown furnaces in a series
configuration use one high turndown
furnace and one 2-stage furnace
*High turndown furnaces in a parallel
configuration use two high turndown
furnaces, controlled in parallel
Three Furnace
Unit
12:1 - uses one 4:1 modulating furnace,
one 2 stage furnace and one 1-stage
furnace
*High turndown uses one high turndown
furnace, one 2-stage furnace, and one
1-stage furnace
* High turndown furnace patent pending
.
Staged
Single Furnace
Unit
8 stage
Troubleshooting
Furnace