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40
2. 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. 41.
Fig. 39 — Setting Up Installation Guide
Fig. 40 — Positioning Installation Guide
Fig. 41 — Threaded Rod Dimension
Condensate Piping
The unit is supplied with a
3
/
8
-in. ID flexible hose for connec-
tion 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. 42.
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.
Fig. 42 — Condensate Piping
Duct Collars
Up to 2 branch ducts can be attached per unit. Branch duct
and fresh air duct collars can be attached to the unit chassis
by following the steps below:
1. Refer to Fig. 2-4
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.
5. Replace washable filter with the pleated filter provided
with fresh air duct collar kit.
NOTE: See Fig. 2-4 for branch duct and fresh air duct locations
and dimensions.
Piping Installation
1. Branch piping to and from the unit should include swing
joints to allow for expansion and contraction of the pip-
ing 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. 43.
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.
7. On 2-pipe systems with microprocessor controls, install
the factory-provided Changeover Sensor on the main
supply water line upstream from the unit where water
maintains flow. This ensures accurate readings of water
temperature. Wire extension and a plug are included.
Fig. 43 — Installing Piping
AIR VENT
UNION
S
TRAINER
S
HUT-OFF
VALVE
S
UPPLY
RETURN
S
HUT-OFF
VALVE
CIRCUIT
S
ETTER
UNION
2-WAY CONTROL
VALVE
UNION
HO
S
E BIB DRAIN
HOT/CHILLED
WATER COIL