20
2. Adjust the height of the cassette until the guide is level
with the bottom of the false ceiling.
3. Secure the unit in position with locknuts and washers on
both sides of the unit bracket. Ensure the threaded rod
does not protrude more than 2 in. below the mounting
bracket as shown in Fig. 22.
Condensate Piping —
The unit is supplied with a
3
/
8
in.
ID flexible hose for connection to copper or plastic drain
piping.
When installing the unit, the following points should be
remembered:
1. Maximum pump lift is 30 inches.
2. The highest point in the condensate piping should be as
close to the unit as possible. See Fig. 23.
3. Condensate piping should slope downwards in the direc-
tion of water flow with a minimum gradient of 1 inch in
100 inches. There must not be any uphill gradients other
than in the first 30 in. of piping from the unit.
4. When multiple units are connected to a common conden-
sate drain, ensure the drain is large enough to cope with
the volume of condensate from all units. It is also recom-
mended to have an air vent in the condensate piping to
prevent any air locks.
5. Condensate piping must not be installed where it may be
exposed to freezing temperatures.
Duct Collars —
Branch duct and fresh air duct collars can
be attached to the unit chassis by following the steps below:
1. Refer to Fig. 1-3
to become familiarized with knockout
hole locations.
2. The insulation is pre-cut to aid location and removal of
the relevant section. Rub hand across surface of insula-
tion to reveal exact location of knockout.
3. Remove the metal knockout from the chassis.
4. Attach the duct collar to the chassis using self-tapping
screws.
NOTE: Branch ducts are round and 5 to 6 inches in diameter.
Fresh air ducts are 3 in. x 3 in. squares.
Piping Installation
1. Branch piping to and from the unit should include swing
joints to allow for expansion and contraction of the piping
without placing a strain on the unit coil.
2. Install pipe unions and shutoff valves in lines to and from
each coil to allow maintenance or replacement of unit
without shutting down and draining entire system. See
Fig. 24.
3. Include a circuit setter in return line for water flow
regulation.
4. A drain valve (hose bib) should also be provided for each
coil line to allow removal of water from the coil if located
in an area subject to freezing.
5. It is advisable to use a pipe line strainer before each coil.
6. Provide adequate pipe hangers, supports, or anchors to
secure the piping system independently of the unit.
Piping Insulation —
Chilled water and condensate pipes
should be insulated right up to the unit chassis to prevent con-
densation which can damage the ceiling and objects located be-
low the piping. Chilled water valves must also be insulated to
prevent sweating.
Fig. 20 — Setting Up Installation Guide
a42-4023
Fig. 21 — Positioning Installation Guide
a42-4024
Fig. 22 — Threaded Rod Dimension
a42-4020
Fig. 23 — Condensate Piping
a42-4021
Fig. 24 — Installing Piping
A42-4025_LA.eps
