Lobb WS-3300 Installation Instructions
Attention Installer: Read Complete Safety and Installation Instructions Before Starting.
Introduction
The Lobb WS-3300 is the most efficient flo-thru whole
house humidifier you could have chosen to install. It
uses 75% less water that other comparable flo-thru
models on the market today.
Installation Instructions
1. It is recommended that the WS-3300 be installed on
the return air plenum. However, if this is not accessible,
the warm air plenum can be used. Select a spot on the
plenum that allows for easy access when service or
maintenance is required.
2. Draw a level line for the template on the furnace
plenum. Make sure the bottom of the template is at
least 3 inches above the furnace jacket for the water
supply line and drain hose. Place mounting template in
position, making sure it is level. See sketch #726.
3. Drill the four (4) mounting hole locations. They are
marked with a +. Cut the inside opening of the mounting
template, leaving the outside lines visible. Be careful to
avoid injury from sharp edges. See sketch #726
4. Remove the top cover of the WS-3300 and set aside.
Lift front of distribution tray and remove evaporator pad
first, then remove distribution tray.
5. Carefully place the WS-3300 cabinet into the opening
in the plenum. Insert the 4 mounting screws into the
holes and tighten the cabinet to the plenum.
Make the by-pass connection using the necessary hard
pipe and elbows or flex duct.
6. The WS-3300 is designed with a reversible side
cover plate for the by-pass opening. Carefully select
the location for the by-pass connection, and install a
snap-in collar. Secure side cover plate on opposite
opening with nut and bolt provided.
7. Re-install distribution tray. Lift the front on the distri-
bution tray, slide evaporator pad into position, then
lower distribution tray on top of the evaporator pad.
Sculptured bottom of evaporator pad should fit into pan
liner.
8. Select the nearest water pipe, to install the water line
to the humidifier. Tap into the water supply line with the
self-tapping saddle valve furnished. The saddle valve
must be completely open or closed. Connect an appro-
priate length of ¼” plastic-poly tubing (not supplied)
and connect it from the saddle valve to the inlet side of
the solenoid. A hard water line is preferred.
Use of copper tube voids warranty
9. Install the humidistat per instructions provided with
the humidistat. The general rules for the installation of
thermostats also apply to the humidifier.
10. Wiring – 24 volts. All wiring must comply with local
codes and ordinances. Shut off the furnace power and
locate the blower motor junction box. Mount the 24 volt
transformer on the box and tap the primary 120 volt
leads to the motor wires. Wire the solenoid in series
with the 24 volt terminals on the transformer and
humidistat. See the wiring diagram below.
11. Attach ½ inch I.D. PVC pipe or plastic tubing from
the WS-3300 drain at the bottom of the cabinet to the
nearest floor drain. Make sure the drain pipe is draining
properly and has continuous slope with no traps. PVC
is recommended, however, ½ inch I.D. plastic hose can
be used as long as there is proper slope with no traps.
