Manual 2100-498B
Page 3 of 17
GENERAL
GENERAL INFORMATION
The ventilator should only be installed by a trained
heating and air conditioning technician. These
instructions serve as a guide to the technician installing
the ventilator package. They are not intended as a step
by step procedure with which the mechanically inclined
owner can install the package.
The ventilator housing is shipped in one carton which
contains the electrical harness, miscellaneous hardware
and installation instructions.
The economizer installation will function normally with
the 2-stage thermostats already specified for usage with
this 2-stage cooling unit.
If the “free cooling” of the economizer cannot keep up
with the cooling demand, it will de-energize the
economizer and will then operate on 2nd stage
mechanical cooling. Because of this, all units
equipped with an economizer need to be equipped
with the low ambient control. For field installed
applications, install Bard Low Ambient Control Kit per
Table (below):
If using a Bard Master Controller, the Bard MC3000
controller is designed to control two (2) redundant Bard
Wall Mount units equipped with economizers. Refer to
the MC3000 Installation Manual (or consult Bard
Technical Service) for the required connections and
sequence of operation.
UNPACKING
Upon receipt of the equipment be sure to compare the
model number found on the shipping label with the
accessory identification information on the ordering and
shipping document to verify that the correct accessory
has been shipped.
Inspect the carton housing of each ventilator as it is
received, and before signing the freight bill, verify that
all items have been received and that there is no visible
damage. Note any shortages or damage on all copies of
the freight bill. The receiving party must contact the
last carrier immediately, preferably in writing,
requesting inspection by the carrier’s agent. Concealed
damage not discovered until after loading must be
reported to the carrier within 15 days of its receipt.
DESCRIPTION
The WGEIFM-3C economizer is designed to be used
with Bard W24G to W36G 1-stage cooling, 1-stage
heating gas electric model wall mounts that are
equipped with fan cycling controls. The WGSEIFM-5
economizer is designed to be used with Bard WG*S 2-
stage cooling and W42-60G 1-stage cooling, 1-stage
heating gas electric model wall mounts that are
equipped with fan cycling controls. They are an
electromechanical economizer system designed to
provide “free” cooling where the outdoor air
temperature is cool enough to provide the needed
cooling without running the compressor. When cooling
is needed, the system automatically takes advantage of
the cold outdoor air when available, and uses it for first
stage cooling. Thus reducing the need to run the air
conditioning compressor – providing lower operating
costs and increasing the service life of the equipment. If
the outdoor air gets too warm or humid to be helpful, the
enthalpy control detects the condition and automatically
operates the internal damper and switches on the
mechanical cooling. This is all accomplished
automatically without attention from the user to achieve
maximum savings. See Figure 6 for a block diagram of
the economizer operation logic flow. The unit is
equipped with a full modulating type damper motor,
which controls the damper position to a factory set
minimum supply air temperature.
MODELS
When installed in model series (refer to Table 1), all
EIFM models provide built in exhaust provisions.
When
the damper blade opens to bring fresh air in, the damper
also opens an exhaust relief. The exhaust air will flow
into the condenser section of the unit. The condenser
fan will help draw exhaust air out.
LEDOM HTIWESUROF STINUGNIWOLLOF
5-MFIESGW
S3GW S4GW S5GW
C3-MFIEGW
G42W G03W G63W
C5-MFIEGW
G24W G84W G06W
TABLE 1
1G06W-1G42W6-AMC
S5GW-S3GW82-AMC
D1G06W-D1G42W82-AMC
