Advertisement
Blade
ADJUSTING MINIMUM FLOW (TK-HC, TK-C)
VARITHERM SMALL SQUARE VAV DIFFUSER
Minimum flow is adjusted by turning the damper opening
cam until the damper blades are open the correct amount.
Determine the correct blade opening for the required percent
ADJUSTING MIMINUM FLOW & TEMPERATURE SETPOINTS
minimum flow from the graph in
opening as shown in
Fig. 3
ADJUSTING TEMPERATURE
FIG. 5 PERCENT MINIMUM FLOW VS. BLADE OPENING
SETPOINTS (TK-HC, TK-C)
Fig 5. Percent Minimum Flow vs. Blade Opening
The TK-HC Therma-Fuser diffuser is factory set for
PERCENT of AIR FLOW CAPACITY vs. BLADE OPENING
74° F/28°C for both heating and cooling. Because heat
100
loads in various rooms differ and individual occupants
prefer different temperatures, it is recommended that the
80
thermostats should not be adjusted until after a few days of
operation.
60
Room temperature set points are adjusted by screwing
the thermostats in or out – in for cooler or out for warmer.
40
Determine the set point by aligning the white indicator with
the °F or °C numbers on the temperature scale (See
20
The thermostats may be slightly harder to screw in or out
0
when warm because the shaft is extended, putting more
0
.10
.20
pressure on the thermostat. If you are unable to turn the
(0)
(2.5)
(5.1)
BLADE OPENING — INCHES
thermostat in this situation, cool the thermostat by holding
an ice cube to the large end. The shaft will then contract and
the thermostat will turn easily for adjustment.
FIG. 6 ROOM TEMPERATURE SET POINT ADJUSTMENT
Read setpoints here
Fig 6. Room temperature set point adjustment
RECOMMENDED ADJUSTMENTS FOR
VARIOUS CONDITIONS
Room
Blade
Temp.
Position
Cooling
Too
Open
Adjust cooling for higher room temperature set point.
Mode
Cold
(Screw cooling thermostat out.)
Closed
Therma-Fuser diffuser is correct. Check if cooling is
still required, and if not, turn cooling unit off.
Too
Open
Therma-Fuser diffuser is correct. Check for lack of
Warm
air or for too warm air temperature.
TK-HC
Closed
Adjust cooling thermostat for lower room tempera-
ture set point. (Screw cooling thermostat in.)
Heating
Too
Open
Therma-Fuser diffuser is correct. Check for lack of
Mode
Cold
air or too low air temperature.
Closed
Adjust heating thermostat for higher room tempera-
ture set point. (Screw heating thermostat out.)
4
VARITHERM SMALL SQUARE VAV DIFFUSER - Manual | priceindustries.com/vavdiffusers
TK-HC
Too
Open
Adjust heating thermostat for lower room tempera-
Warm
ture set point. (Screw heating thermostat in.)
Closed
Therma-Fuser diffuser is correct. Check if heating is
still required, and if not, turn it off.
Small Steel Rule
5. Measure the blade
Fig.
and adjust the damper opening cam.
.30
.40
.50
.60
.70
(7.6)
(10.2)
(12.7)
(15.2)
(17.8)
(MM)
Thermostats
Recommended
Action
BLOW PATTERNS (TK-HC, TK-C, TK
Adjusting Minimum Flow (VKD-HC, VKD-C)
A major selling feature of the TK-HC diffusers is the a
Minimum flow is adjusted by turning the damper opening
to easily add or remove blow patterns in the field. Thi
cam until the damper blades are open the correct amount.
done by blocking the air off behind the blades on the
Determine the correct blade opening for the required percent
appropriate sides.
minimum flow from the graph in Fig. 5. Measure the blade
DO NOT:
opening as shown in Fig. 3 and adjust the damper opening
— Disconnect the spokes.
— Tape, screw or otherwise lock the blade closed.
cam.
— Block the venturi nozzle.
Adjusting Temperature Setpoints
DO block air flow behind the blades or between the
standoffs. (Standoffs are the supports between the
The VKD-HC Varitherm Small Square VAV diffuser is factory
Fig.
6).
housing and the diffusion plate.) Ways to do this are:
set for 74° F/28°C for both heating and cooling. Because heat
1.
loads in various rooms differ and individual occupants prefer
.80
different temperatures, it is recommended that the thermostats
(20.3)
should not be adjusted until after a few days of operation.
Room temperature set points are adjusted by screwing
2. Field installed directional baffles. These are made
the thermostats in or out – in for cooler or out for warmer.
Determine the set point by aligning the white indicator with the
°F or °C numbers on the temperature scale (See Fig. 6).
The thermostats may be slightly harder to screw in or out when
warm because the shaft is extended, putting more pressure
on the thermostat. If you are unable to turn the thermostat in
The rule for blocking the appropriate side is: Always b
this situation, cool the thermostat by holding an ice cube to the
the side adjacent to the thermost. (See
large end. The shaft will then contract and the thermostat will
Figure 3 @200%
When blocking for direction, reduce maximum air vo
turn easily for adjustment.
for a given static pressure and throw in the performan
guide by:
Appearance
Panel
Fig 7. Field installed foam baffle
Gauge
1250 to
2300 fpm
This unbalances the loads on the center bearings.
Factory installed directional baffles. These are str
metal wrapped around the standoffs to block one
or three sides. These can be removed in the field
first removing the diffusion plate assembly.
1-1/8"/ 28.575mm diameter x 5-5/8"/143mm lon
insulation (Armaflex) for 3/8"/ 9.525mm refrigera
lines. Insert between the housing and the diffusio
plate/blade assembly and wedge between the sta
(See Fig. 7). Take care to clear the damper hinge
that the damper operates freely.
Diffusion
Damper
Housing
Blow Patterns
3 way (D3)
2 way opposite (D2)
2 way corner (D2C)
1 way (D1)
Probe
Figure 7 @ 200%
for exam
Fig. 8
Reduction
.80
.64
.59
.45
THERMA-FUS
DIFFUSER
Advertisement
