Aprilaire 600a Installation Instruction

READ COMPLETE SAFETY INSTRUCTIONS AND INSTALLATION TEMPLATE BEFORE STARTING

This product must be installed by a qualified heating and air conditioning contractor. Failure to do so could result in serious injury from electrical shock.

This product must be installed in compliance with all local, state and federal codes.

ATTENTION INSTALLER:

AUTOMATIC HUMIDIFIER MODEL 600

The Model 600 Aprilaire can be installed on either

the supply or return plenum of a forced air

handling system and is easily reversible for

installation with right hand or left hand bypass duct

connections. The humidifier dimensions and

serviceability must be considered when selecting

the best location for the humidifier. Here are 2

examples of many types of installations.

P.O. BOX 1467 • MADISON, WI 53701-1467 • CALL 800/334-6011 • FAX [phone]

RETURN

SUPPLY

RETURN

SUPPLY

Horizontal

Upflow

90-1110

90-1079

WARNING

1. ELECTRICAL SHOCK HAZARD.

Disconnect electrical power to the
furnace before starting installation.
Failure to do so could result in
serious injury from electrical shock.

2.

SHARP EDGES HAZARD. Sharp

edges may cause serious injury from
cuts. Use care when making plenum
openings and handling ductwork.

3.

RISK OF SCALDING. Water

temperature over 125°F can cause
severe burns and scald instantly.
Shut off the hot water supply before
disconnecting or tapping into any
hot water supply line.

SPECIFICATIONS

HUMIDIFIER DIMENSIONS

Width (including solenoid valve): 153⁄8Ó

Height

(including drain spud): 15

3

⁄4”

Depth

: 10

1

⁄4”

BYPASS DUCT OPENING

6” diameter

PLENUM OPENING

97⁄8”W x 125⁄8”H

WATER FEED RATE

3 gph

ELECTRICAL DATA

24 VAC-60 Hz, 0.5 AMP

CAUTION

1. Do not install humidifier where freezing temperatures
could occur. The water line could freeze and crack
causing water damage to the home.

2. Do not install humidifier or bypass connection on the
furnace jacket.

3. Do not install humidifier or bypass connection on a
plenum face where the blanked off ends of the cooling
coil will restrict air movement through the humidifier.

4. Do not set humidity level above recommended or to
recommended level if condensation exists on inside
windows of any unheated space, as condensation
damage may result. Excess humidity can cause
moisture accumulation which can allow the possibility
for mold growth in the home.

5. Do not connect Model 600 transformer to
blower motor wiring. Premature component
failure may result.

6. When installing Humidifier Control on
downflow furnace, ensure blower continues to
run after a heat call is satisfied to eliminate
high temperatures from damaging the Control.

7. Do not install humidifier where water pressure
exceeds 125 psi, since damage to the
humidifier may result. Follow codes in effect
concerning pressure reduction.

8. Do not install humidifier on systems with
greater than 0.4 in. wg pressure differential
between supply and return plenums.

RISK OF PROPERTY AND EQUIPMENT DAMAGE.

INSTALLATION

OPTIONS

WIRING DIAGRAM

(SEE STEP 8 ON BACK AND “HUMIDIFIER CONTROL SAFETY AND INSTALLATION INSTRUCTIONS” FOR DETAILED WIRING INSTRUCTIONS)

NOTE

FOR INSTALLATION IN MANUAL MODE,
REPLACE OUTDOOR TEMPERATURE
SENSOR WITH PLASTIC RESISTOR CASE
AND ATTACH MANUAL FACE PLATE.
SEE “HUMIDIFIER CONTROL SAFETY
AND INSTALLATION INSTRUCTIONS”
INCLUDED WITH EACH HUMIDIFIER.

COMMUNICATION

TERMINALS FOR 8570

THERMOSTAT

24 VAC FURNACE ACCESSORY TERMINALS

(10 VA MINIMUM) OR

24 VAC TRANSFORMER (10 VA MINIMUM)

IMPORTANT

DO NOT WIRE TRANSFORMER
INTO FURNACE BLOWER CIRCUIT.

WATER SUPPLY

CONNECT DRAIN LINE HERE

SHUT-OFF

(SADDLE VALVE)

YELLOW 24 V

SOLENOID

VALVE WIRES

I-

R

I+

C

24V

ODT

H

FURNACE

BLOWER MOTOR

NORTH, EAST

OR WEST SIDE

OF HOME

OUTDOOR

TEMPERATURE

SENSOR

ABOVE EXPECTED

SNOW LINE

COMMON

MODEL 50 CURRENT SENSING RELAY
(NOT SUPPLIED) REQUIRED IF 24 VAC
POWER SOURCE FOR CONTROL IS
POWERED CONTINUOUSLY.

DO NOT INSTALL IN TRANSFORMER
PRIMARY CIRCUIT.

READ COMPLETE SAFETY INSTRUCTIONS AND INSTALLATION TEMPLATE BEFORE STARTING

TEMPLATE MUST BE LEVEL

– TOP –

READ REVERSE SIDE FIRST! READ REVERSE SIDE FIRST!

IMPORTANT! Be sure owner’s manual containing

instructions for operation and warranty information is given to

owner in order to avoid unnecessary calls. Warranty is void unless

humidifier is installed by qualified heating and air conditioning

contractor due to possible misapplication of product.

1. Remove front cover by pressing

center tabs on top and bottom of the
cover (1) and base (2). Pull feed tube
(3) out of the water distribution tray
(4). Tip the Water Panel

®

Evaporator
assembly forward and lift it out of
the humidifier. (See Figure 1)

2. The humidifier comes assembled

for left side discharge. If converting
to right side discharge, the base can
be rotated so round collar is facing
to the right. Swap the location of the
hole plug (10) and drain spud (9) if
using a right side discharge. To
remove the cap, push and twist from
inside the housing while lifting the
cap up slightly on the outside. To
remove the drain spud, twist and
push from the outside of the base.

3. Using a level, position this

template at least 3 inches above the
furnace housing or cooling coil, if
applicable, for clearance of the
drain line. Trace around template
edges. Remove the template and
accurately cut the plenum opening
9

7

⁄8” x 125⁄8”, being careful to avoid

injury from sharp edges.

4. Place the humidifier into the

plenum opening, install six sheet
metal mounting screws (not
furnished) at the top and sides of the
humidifier interior.

5. Install a 6”collar in a convenient

location on the opposite plenum.
Attach a 90° elbow and measure the
length of 6” round duct required to
make the connection. The design of
the humidifier collar provides a solid
connection with the bypass duct
through the use of inside support ribs
and pre-formed holes for sheet metal
screws. Slip the duct inside the
collar of the humidifier, up to the
support ribs. Using the pre-formed
holes at the top and bottom of the
humidifier collar, secure the duct to
the humidifier collar with two sheet
metal mounting screws (not
furnished). Support bypass ducts
longer than 4 feet to prevent sagging.

6. Reinstall the Water Panel

®

Evaporator assembly back into the
base, with the bottom of the scale
control insert (6) sitting firmly in the
inside of the drain spud (9). Push the

feed tube back into the water
distribution tray. (See Figure 2) Put
the front cover back on. If the
nameplate (11) is upside down,
remove it by gently squeezing the
tabs of the nameplate from inside
the cover and pushing out. Rotate
the nameplate so it is right side up,
and snap back into place. Turn
damper handle (8) to the open
position “WINTER” for the heating
season, or closed position
“SUMMER” for the cooling season.

7. Install the Aprilaire Humidifier

Control in the return duct using the
installation instructions enclosed
(see Wiring Diagram, opposite side).
For detailed installation and wiring
instructions, see “Humidifier Control
Safety and Installation Instructions”
included with the humidifier

8. The Automatic Humidifier Control

must be powered by a 24 VAC power
source connected to the “R” and “C”
terminals on the Control. The 24 VAC
humidifier solenoid valve receives
power through the Control. Connect
the yellow wires to the “H” terminals

NOTE: BEFORE LEAVING
THE JOB SITE, MAKE SURE:

1. Saddle valve is fully open.

2. All plumbing connections
are watertight.

3. Humidifier functions
properly.

4. Bypass damper is in
proper position.

Figure 1 Figure 2 Figure 3

10007019 B2204009A 05.06

90-1067 90-1068 90-1069

90-1070

FURNISHED ITEMS

ITEMS NOT FURNISHED

Built-in bypass damper

24 VAC Transformer
Automatic Humidifier Control
Automatic Humidifier Control

Installation Sheet

Saddle valve

Humidifier Installation Template

Mounting screws (sheet metal screws)

Water supply line (1⁄4” copper)

Drain line (1⁄2” I.D. hose)

Low voltage wire
Bypass ductwork

Model 50 Current Sensing Relay

(if required)

on the Control. Do not connect yellow

wires to “ACC” or “HUM” terminals
on furnace or damage to the
humidifier could result.

In order for the humidifier to turn on,
the furnace blower must be
operating and the control must be
calling for humidity. The interface
between the Model 600 humidifier
and the furnace to detect blower
operation can be accomplished
several different ways:

A. If the Control is powered directly
from 24 VAC “ACC” or “HUM”
terminals on the furnace, which are
activated only during furnace blower
operation or a heat call, then the
yellow wires from the humidifier can
be connected directly to the “H”
terminals on the Control.

B. If the Control is powered by a
transformer connected to 120 VAC
“ACC” or “HUM” terminals on the
furnace, which are activated only
during furnace blower operation or a
heat call, then the yellow wires from
the humidifier can be connected
directly to the “H” terminals on the
Control.

C. If the Control is powered from a
continuous 24 VAC source, then a
Model 50 Current Sensing Relay (not
included) must be installed in the
humidifier circuit. (Yellow wires
connected to “H” terminals on
Control.)

Do not wire transformer into furnace
blower circuit. The transformer can

be powered from the 120 VAC line
before it enters the furnace.

9. Tap into a water supply line with

the saddle valve furnished. See
instructions on saddle valve package.
The humidifier will function with cold,
hot, softened or unsoftened water.
The use of service hot water
(140°F MAX.) and constant blower
operation will provide maximum
evaporative capacity. When

installing humidifier on heat pump

system, humidifier must be supplied
with service hot water.

NOTE: The saddle valve is designed
to be fully opened or closed. Do not
use it to regulate water flow.

10. Connect tubing from the saddle

valve to the inlet side of the solenoid
valve using

1

⁄4” O.D. copper tubing

(not furnished). DOUBLE WRENCH

TO PREVENT LEAKING!
(See Figure 3)

11. Drain spud is designed to

accept

1

⁄2” I.D. plastic hose (not
furnished). Run drain line from drain
spud to floor drain. CAUTION: If hose

clamp is used, do not over tighten,
drain spud could crack. Be sure
drain line has continuous slope.
NOTE: Do not sweat or directly
attach metal drain line to fitting. Do
not use solvent type adhesive when
connecting plastic drain line, since
damage to fitting could result.

12. Open saddle valve completely

and turn on furnace. Turn up
humidifier control so that humidifier
will turn on. Allow humidifier to run
until water is observed coming out
of the drain line. Check to see if
humidifier and saddle valve are
watertight. Check operation to make
sure that all electrical components
function properly by utilizing
humidification system check-out
section in the “Humidifier Control

Safety and Installation Instructions”.
Set humidifier control to

recommended level.

1. Front Cover

2. Base

3. Feed Tube

4. Water Distribution Tray

5. Water Panel Evaporator

6. Scale Control Insert

7. Integral Damper

8. Damper Handle

9. Drain Spud

10. Hole Plug

11. Nameplate

12. Solenoid Valve

PARTS LIST

2

7

10

12

4

3

5

9

8

6

1

11