Model IGX Make-Up Air
38
®
Start-Up
Repeat
Supply Fan, Pre-Start Checks and Start-Up;
Pre-Start: Indirect gas-Fired Heating; and Start-Up:
Indirect gas-Fired Heating
sections in this IOM. This
will ensure that the gas and air are set properly before
the heating season begins and should lead to trouble
free operation all winter.
Gas Train
Check the gas connections, joints and valves annually
for tightness. Apply a soap and water solution to all
piping; watch for bubbling which indicates a leak.
Evaporative Cooling Module
Shut off the water and drain all exposed lines when the
outside temperature drops below 45ºF (7.2ºC).
Clean all interior parts of any mineral deposits or foreign
materials that may have built-up during the cooling season.
Replace any worn or non-functioning parts.
Winterizing Chilled Water Coils
During the winter, chilled water coils need to be
protected against freezing. Manufacturer recommends
protecting the coils by either blowing-out the coils or by
flushing the coils.
Blowing-Out Coils
1. Close valves on the supply and return lines.
2. Open drain valves and/or drain plug. Remove vent
plug to allow coil to drain faster.
3. After coil is fully drained, connect a blower to the
caps. Do not connect the blower to the air vent or
drain plug.
4. Close the vent plug on the header that the blower
is connected to. Open the drain valve or cap on the
other header.
5. Turn on blower for 30 minutes. Place mirror at
discharge. If the mirror fogs up, repeat procedure
until no fog appears on the mirror.
6. After drying the coil, wait a few minutes then repeat
Step #5.
7. Leave drains open and do not install plugs until
beginning of cooling season.
Maintenance
Seasonal: Heating/Cooling
Flushing Coils
Manufacturer recommends the use of inhibited glycol
(such as propylene or ethylene) to flush water coils
to protect against freezing. Additionally, the use of
inhibited glycol provides corrosion protection.
The table below indicates the percentage of glycol
required to prevent freezing in a coil at a given outdoor
air freeze point. Completely fill coil with solution. Drain
coil. Residual glycol fluid per these concentrations can
be left in the coil without concern of freezing. Recovered
fluid can be used to flush other coils.
Combustion Blower Motor
Motor maintenance is generally limited to cleaning.
Cleaning should be limited to exterior surfaces only.
Removing dust and grease build-up on the motor
housing assures proper motor cooling. Use caution
and do not allow water or solvents to enter the motor
or bearings. Under no circumstances should motors or
bearings be sprayed with water, steam or solvents. The
motor bearings are pre-lubricated and sealed, requiring
no further lubrication.
Percent of
Ethylene
Glycol
by Volume
Freeze Point
Percent of
Propylene
Glycol
by Volume
Freeze Point
ºF
ºC
ºF
ºC
0
32
0
0
32
0
10
25
-4
10
26
-3
20
16
-9
20
19
-7
30
3
-16
30
8
-13
40
-13
-25
40
-7
-22
50
-34
-37
50
-28
-33
60
-55
-48
60
-60
-51
