Aprilaire 1770A - LOCALIZED INSTALLATION AND OPERATION

FIGURE 6 – Drain Trap
90-961
MECHANICAL INSTALLATION (CONTINUED)
DRAIN
1. Adjust feet of dehumidifier to allow a 2-1/2” minimum clearance
for drain trap. See Figure 6. Use the 90° elbow if necessary for
clearance restrictions. See Figure 7.
2. Use PVC primer and cement for drain assembly to the dehumidifier
drain outlet.
3. Complete assembly by piping the 3/4” PVC trap to a drain or
condensate pump. Make sure the drain line has a constant
downward slope and is not kinked.
4. To prime the drain trap and to verify the drain line is not blocked,
slowly pour a pint of water into the dehumidifier drip pan located
below the coil.
CAUTION
1. Drain trap must be primed with water before use.
2. A condensate pan with a float switch is required in attic
installations.
High Side
Low Side
Drain Outlet
Drain Trap
2-1/2
Arrows on
trap show
water flow
direction
FIGURE 7 – Drain Trap with 90° Elbow
90-961
High Side Low Side
Drain Trap
90° PVC Elbow
FIGURE 8 – Float Switch Wiring
If the dehumidifier is installed in an attic or another location requiring
leak protection, the unit should be placed in a condensate pan with
a normally closed, condensate overflow safety switch (float switch).
Remove the jumper from the float switch terminals on the control board
and wire the float switch to the terminals. See Figure 8.
FLOAT
SWITCH
LOW VOLTAGE NORMALLY
CLOSED FLOAT SWITCH
90-1429
FLOAT SWITCH
6