THERMA-FUSER
™
THERMALLY POWERED VAV DIFFUSER
INSTALLATION, BALANCING & MAINTENANCE
FORM 10.2 REV
1704
Copyright © Acutherm 2003
MODULAR VAV SYSTEMS
Models:
ST-C
VAV cooling only.
ST-HC
VAV cooling and VAV heating.
(See Fig. 1 for dimensions.)
TABLE OF CONTENTS
Installation Instructions . . . . . . . . . . . . . . . . . . 1
System Balancing . . . . . . . . . . . . . . . . . . . . . . . . 2
Adjusting Miminum Flow . . . . . . . . . . . . . . . . . 2
Adjusting Temperature Setpoints . . . . . . . . . . 3
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Controlling the System . . . . . . . . . . . . . . . . . . . 3
Trouble Shooting . . . . . . . . . . . . . . . . . . . . . . . . 4
Blow Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Ten Year Warranty . . . . . . . . . . . . . . . . . . . . . . . 6
DAMAGED FREIGHT CLAIM PROCEDURE
When the diffusers are received, inspect for damage which
may have occured during shipment. If damage is evident, it
should be noted on the carrier's freight bill. A written request
for inspection by the carrier's agent should be made at once.
STORAGE
Cartons should always be stacked on end with the arrows on
the cartons pointing up. Do not stack cartons flat on the
sides. Excessive weight may cause damage to the diffusers.
Do not store for prolonged times at temperatures exceeding
130°F/56°C.
IDENTIFICATION
Diffusers are factory shipped one per carton. The model des-
ignation is on the diffuser and on the carton.
INSTALLATION PRECAUTIONS
When installing diffusers, make sure construction debris does
not enter the diffuser or duct system.
Because the models ST-C and ST-HC control room tempera-
ture by sensing the room air induced up the center of the
room, care should be taken not to disturb room air induction
and entrainment. For example, location next to walls or drop-
ped lights results in the reflection of primary air back at the
Therma-Fuser diffuser and should be avoided. A three-way
blow Therma-Fuser diffuser should be used in this instance if
either the light or the Therma-Fuser diffuser cannot be relo-
cated.
INSTALLATION INSTRUCTIONS
1. Inspect the carton for damage before opening. Notify car-
rier if external damage exists. Submit all claims for ship-
ping damage to the carrier.
2. Move diffusers (in cartons) to installation area. Note unit
identification.
3. Remove cardboard box and cardboard insert. Discard
packing material.
4. If other than 4 way blow pattern is factory installed, note
the "AIRFLOW" markings on the top of the diffuser and
locate those sides in the proper direction.
5. Install in ceiling grid. Install T-bar support wire close to
each corner of diffuser. Make sure that only wire sus-
pended T-bars are used to support diffuser weight. (Adap-
tor frames are available for other than lay in ceilings.)
6. Connect and secure the supply duct to the collar. Flexible
duct should NOT be formed in a centerline radius of less
than 1½ times the duct diameter.
7. Do NOT reset the temperature set point on the ST-C and
ST-HC models until the space is occupied. The set point is
factory preset for average conditions (74°F/23°C).
8. Balance the system. See
System Balancing
.
9. After the air conditioning system is started and after the
space is occupied
, where necessary adjust the temperature
set point on ST-C and ST-HC models to suit the occupant.
See
Adjusting Temperature
.
OPERATING INSTRUCTIONS
Operating instructions for models ST-C and ST-HC are
located on the back of the appearance panel. See
Fig. 2.
NECK SECTION
*595±2mm Square with 16±2mm lip available
—specify 595mm square.
Fig 1. Dimensions
Inlet
Desig-
nation
6
8
10
12
OD
Inches
±
1
/
16
5
15
/
16
7
15
/
16
9
15
/
16
11
15
/
16
mm
±3
150
200
250
300
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