Aprilaire 720 Cleaning Instructions

Hard Water
Installation
Annual replacement of the orifice and cleaning of the
valve is required to maintain optimal performance.
*To determine water connection, trace the water inlet (L) back to the water source to see if it is connected to a softener or contact your
service technician. Itchy skin, poor soap lather, and mineral residue or buildup on faucets or appliances are signs of hard water.
WARNING: Take note of humidifier control setpoint and turn dial to off position before starting.
1. Remove cover (A) by depressing latch (B) and pulling
away from base (C). Remove HydroCore (D) then
brush away any mineral deposits from the base.
2. Plug the drain port (E) or raise the end of the flexible drain
line (F) above the valve and secure to create a trap.
3. Pour white vinegar into the valve cup (G) up to the
clean line (H). Soak for up to 30 minutes.
4. Use a small plastic bristle brush to remove buildup in the
valve cup then drain vinegar solution. Flush with water.
5. Replace the rubber seal cap (I) and orifice (J) assembly
(PN: 70000037). See Orifice Replacement Instructions.
6. If applicable, remove the drain line and flex it to loosen
any mineral deposits or blockages then flush with water.
If it does not clear, replace it. Reattach drain line,
ensuring it has a constant downward slope and is not
flattened or blocked.
7. Install fresh HydroCore and test to confirm proper
function.
NOTE: Inlet strainer is designed to last for the life of the solenoid valve assembly and should not be removed from the water inlet (L).
Orifice Replacement Instructions
REQUIRED ANNUALLY FOR HARD WATER
1. Remove rubber seal cap (I) from the orifice (J).
2. Using the wings on the orifice, rotate it counterclockwise to carefully loosen
*
and remove it from the valve assembly. Ensure no debris enters the orifice
cavity (K).
3. Insert the new orifice, turn clockwise to tighten (finger-tight plus 1/8 to 1/4
turn-do not over-tighten), and press the rubber seal cap onto the orifice.
*If necessary, use an 11/16" socket or pliers to help remove the orifice.
10021529B • 01.25
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AprilAire reserves the right to change specifications without notice.
Cleaning Instructions
for Humidifiers with HydroCore
*
Soft or Softened
Water Installation
Replace the orifice and clean the valve
every 3 years or as needed based on usage.
A
B
I
J
H
K
G
L
E
ASSEMBLY
A. COVER
B. LATCH
C. BASE
D. HYDROCORE L
E. DRAIN PORT
F. DRAIN LINE
(Included with Hard Water Kit)
*
F
C
VALVE
G. VALVE CUP
H. CLEAN LINE
I. RUBBER SEAL CAP
J. ORIFICE
K. ORIFICE CAVITY
L. WATER INLET
Contact
AprilAire
Technical
Support
for details:
800.334.6011
™
D