1. Open all the electric switches before starting any
servicing.
2. Remove the cover of the return piping located
in the panel, breaking the connection tags with
a screwdriver and a hammer.
3. In order to remove the cover of the supply piping
break the front and right connection tags with
a screwdriver and a hammer. Push the grid
downwards in order to break the back and the
left portion of the tags.
4. If the unit piping must be fastened to the fl anges
of the vertical opening of the unit base panel
(only for jackstand applications), make it at this
moment.
5. It is recommended that the insulation of the base
panel around the vertical return air opening
perimeter is fastened to the base panel with an
aluminum belt. The applicable local codes can
require an aluminum belt to prevent the glass
wool from being exposed.
6. Cover the two horizontal conduit openings with
the conduit covers of the conduit cover kit. Make
sure the opening is watertight and air tight.
7. After completing the unit conversion, perform
all the safety and start-up controls of the unit.
AIR INJECTION
Picture 4 – Openings for the Injection and
Vertical Return Piping
AIR
RETURN
NOTE: The design and installation of the piping
system must comply with all NFPA standards for
the insulation of ventilation and air conditioning
systems for non-residential types; NFPA 90A for
residential types; NFPA 90B; and with all the local
codes and ordinances.
Adhere to the following criteria when selecting,
dimensioning and installing the piping system:
1. Select and dimension the piping, supply air
stopcocks and return air grids, according to the
recommendations of the American Society of
Air Conditioning, and Refrigeration Engineers
(ASHRAE).
2. Use a fl exible joint between the hard piping and
the unit in order to avoid the transmission of
the vibration. The transition coupling can be
screwed or fastened to the piping louvers. Use
proper joints to guarantee an hermetic sealing
for the water and air.
3. The units are supplied from factory with an air
fi lter. To take it out, it is necessary to remove the
cover located on the opening for the horizontal
fl ow return.
4. Dimension the piping for the maximum required
air fl ow (either for heating as for cooling), for the
unit that is being installed. Do not let the piping
size abruptly increase or reduce, otherwise the
performance can be affected.
AIR INJECTION
INJECTION
Picture 5 – Openings for the Injection and
Horizontal Return Piping
AIR
RETURN
RETURN
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