Condensate Drain - Carrier AERO 39MN Installation, Start-Up And Service Instructions Manual

LEGEND
ASC — Auxiliary Side Connector
TXV — Thermostatic Expansion Valve
Refrigerant Check Valve
Condensate Drain —
drain line at the units drain connection; use 1
pipe. See Fig. 78A and 78B for correct drain layout. Ensure
adequate depth below base rail for the condensate trap.
When calculating trap depth on draw-thru or blow-thru ap-
plications, remember that it is not the total static pressure but
the upstream or downstream static resistance that is trapped
against. For instance, when calculating the trap depth for a
cooling coil condensate pan on the draw-thru side, trap
against the coil pressure drop in that coil section and any oth-
er pressure drops upstream of it.
Fig. 78A — Condensate Drain, Draw-Thru
Trapping (All Sizes)
Fig. 77 — Hot Gas Bypass Piping
Install a condensate-trapping
/ -in. standard
1
2
a39-4307
a39-4178
ENSURE ADEQUATE
HEIGHT/CLEARANCE
FOR DRAIN TO FLOOR
Fig. 78B — Condensate Drain, Blow-Thru
Trapping (All Sizes)
Using Fig. 79A and 79B, P
trap depth height.
For the draw-thru example, P
the cooling coil section plus all upstream static pressure,
2.5 inches. To account for such fluctuations as dirty filters,
1 inch is added to P for the trap depth height (see Fig. 79A).
1
Traps on draw-thru units must store enough condensate to
prevent losing the drain seal at start-up. The "
dimension ensures that enough condensate is stored.
For the blow-thru example, P
positive pressure which is the fan's external pressure of
2.3 inches minus any static pressure losses between the fan and
drain, in this case 1.2 in. wg from the cooling coil (see Fig.
79B).
For all units, provide condensate freeze-up protection as
required. On units with internal spring isolators, be sure the
unit is mounted to allow sufficient clearance for the required
drain trap depth.
89
a39-4439
P + 1/2"
1
1/2"
MINIMUM
can be calculated to determine
1
is equal to the static pressure in
1
1 / P minimum"
2 1
is equal to the coil's maximum
1
114