Liebert Mini-Mate2 MCD24A, Руководство пользователя, Страница: 26 / 80

Site Preparation and Installation
Liebert
®
Mini-Mate2
™
18
Plenum Installation
The 2- and 3-ton non-ducted evaporators can use the optional ceiling-mounted plenum to provide
four-way air distribution. The plenum fastens to the bottom of the evaporator. The plenum includes a
16 in. x 25 in x 4 in (406x635x102mm) MERV 8 filter (per ASHRAE 52.2-2007).
1. The evaporator should be mounted above the bottom of the T-bar supports with at least 30 in.
(762mm) clearance from return air end to wall (for replacing filter).
2. Check the contents of the plenum kit.
3. Follow the installation instructions included with the plenum kit.
Connections for Ducted Systems
In a ducted configuration, the direct drive evaporator has a maximum allowable external static
pressure of 0.3" wg (7.6 mm). Use flexible ductwork or non-flammable cloth collars to attach ductwork
to the unit and to help control the transmission of vibrations to building structures. Insulation of
ductwork is vital to prevent condensation during the cooling cycle. The use of a vapor barrier is
required to prevent absorption of moisture from the surrounding air into the insulation.
If the return air duct is short, or if noise is likely to be a problem, sound-absorbing insulation should
be used inside the duct. Ductwork should be fabricated and installed in accordance with local and
national codes.
5.5.3 Piping Connections and Coolant Requirements
The following pipe connections are required:
• A drain line from the evaporator coil drain pan (This line also serves as the drain for the optional
humidifier.)
• A drain line from the secondary drain pan beneath the unit.
• A water supply line to the optional humidifier (if applicable).
• Refrigerant piping connections between the evaporator unit and the condensing unit (air, water,
or glycol). If the evaporator unit is chilled water, connections to the building chilled water source
are required.
Drain Line
NOTICE
Risk of water backing up in the evaporator coil drain line. Can cause building and equipment
damage from overflowing water.
Do not install an external trap in the drain line. This line already has a factory-installed trap
inside the cabinet.
This line may contain boiling water. Use copper or other suitable material for the drain line.
A 3/4 in. (19.1 mm) NPT female connection is provided for the evaporator coil condensate drain. This
line also drains the humidifier, if applicable. The drain line must be located so it will not be exposed to
freezing temperatures. The drain should be the full size of the drain connection.
The evaporator drain pan includes a float switch to prevent operation if drain becomes blocked.
NOTE
Do not operate the unit without filters installed in the return air system.
Table 7 Cooling unit air flow at 0.3 IWG (75PA) ESP
Fan Speed
2 Ton
CFM (CMH)
3 Ton
CFM (CMH)
High 885 (1504) 1250 (2124)
Low 800 (1359) 1000 (1699)