14
McQuay IM 672-3
Installation Guidelines
Water Heating Coils
•
Water supply and water return connections extend through
the end panel of the coil section. All connections are labeled
on the end panel.
•
Water supply and water return connections are male NPT
iron pipe.
•
When installing couplings, do not apply undue stress to the
connection extending through unit panel. Use a backup pipe
wrench to avoid breaking the weld between the coil
connection and header.
•
Follow recommendations of the control manufacturer
regarding types, sizes, and installation of controls.
•
Do not use hot water coils with entering air below 40°F.
•
If fresh air and return air are to be heated by a hot water coil,
carefully design the system to provide thorough mixing
before air enters the coil.
•
To prepare coils for winter operation, see “Removing and
Replacing Components” on page 27.
Drain Pan Traps
Run drain lines and traps full size from the drain pan
connection. Install drain pan trap to allow condensate to drain
freely. On both blow-through and draw-through units, the trap
depth and the distance between the trap outlet and the drain
pan outlet must be twice the static pressure in the drain pan
section under normal operation so the trap remains sealed. See
Figure 24
.
Figure 24: Allow adequate distance between trap outlet
and drain pan outlet
Internal Isolation Assembly Adjustment
On units with internally isolated fan and motor assemblies, the
assemblies are secured for shipment.
Before operating the unit:
Remove the shipping brackets and tie-down bolts (see
Figure 26) and discard. The shipping brackets located on the
opposite drive side of the unit are difficult to access from the
drive side of the unit. Either remove them before the unit is
assembled, or remove the panel on the opposite drive side to
gain access.
The spring isolators under the four corners of the fan and
motor assembly are factory adjusted while the fan was not
running. See Table 1 below. With the unit operating at normal
cfm and static pressure, all the isolators should be at the same
height opening. If adjustments are required, loosen the 1/2"
cap screw on top of the isolator and turn the adjusting bolt to
lower or raise the fan and motor base. Retighten the cap screw
when adjustments are completed.
For models 040 through 090, the isolators should be at equal
height during fan operation (6"). Center the fan outlet in the
outlet panel opening. If adjustment is required, loosen the cap
screw on top of the isolator assembly. Turn the adjustment nut
below the fan frame to lower or raise the fan motor and frame
assembly. Retighten the cap screw on top of the isolator
assembly. See Figure 25
.
Figure 25: Adjusting large spring mount assembly
CAUTION
Improper installation, use, or maintenance of water
heating coils can cause equipment damage.
Read and follow instructions carefully.
ATTENTION
Si l’installation, l’utilisation ou l’entretien des
serpentins de chauffage à eau sont inadéquats,
ceci endommagera l’équipement.
Lire et suivre attentivement les instructions.
P r e s s u r e ( P )
a t t h e d r a i n p a n
2 P
2 P
Table 1: Spring mount adjustments
Spring mount adjustment at rest
Fan discharge
position
Top or bottom
horz. H
Downblast
H
Upblast H
Unit sizes 003–035
1
3.75
3.75
4.25
2
4.25
3.75
4.25
3
4.25
3.75
4.25
4
3.75
3.75
4.25
Unit sizes 04–-090
1
6.00
6.00
6.50
2
6.50
6.00
6.50
3
6.50
6.00
6.50
4
6.00
6.00
6.50
Adjusting bolt
6"