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7

CONTROL SETUP

General —

The 35E single-duct VAV (variable air volume)

terminal is designed to supply a varying quantity of cold prima-
ry air to a space in response to a thermostat demand. Some
units have reheat options to provide heating demand require-
ments as well. Most VAV terminals are equipped with pressure
compensating controls to regulate the response to the thermo-
stat independent of the pressure in the supply ductwork.

To balance the unit, it is necessary to set both the maximum

and minimum set points of the controller. The many types of
control options available each have specific procedures re-
quired for balancing the unit.

Set Points —

Maximum and minimum airflow set points

are normally specified for the job and specific for each unit on
the job. Where maximum and minimum airflow levels are not
specified on the order, default values are noted on unit ID label.

Field Adjustment of Minimum and Maximum
Airflow Set Points —

Each 35E unit is equipped with a

flow probe that measures a differential pressure proportional to
the airflow. The relationship between flow probe pressures and
cfm is shown in the Linear Probe CFM vs Pressure Signal
Graph (Fig. 6). This chart is attached to each unit.

System Calibration of the Linear Averaging
Flow Probe —

To achieve accurate pressure independent

operation, the velocity sensor and linear averaging flow probe
must be calibrated to the controller. This will ensure that air-
flow measurements will be accurate for all terminals at system
start-up.

System calibration is accomplished by calculating a flow

coefficient that adjusts the pressure fpm characteristics. The
flow coefficient is determined by dividing the flow for a given
unit (design air volume in cfm), at a pressure of 1.0 in. wg dif-
ferential pressure, by the standard pitot tube coefficient of
4005. This ratio is the same for all sizes if the standard linear
averaging probe is used.

Determine the design air velocity by dividing the design air

volume (the flow at 1.0 in. wg) by the nominal inlet area
(sq ft). This factor is the K factor.

Carrier inlet areas are shown in the table below. The design

air volume is also shown in this table. It can be determined
from this table that the average design air velocity for 35E units
is equal to 2656 fpm at 1.0 in. wg.

.

NOTE: For Carrier ComfortID™ terminals, all flow sizes are normal-
ized using a single Probe Multiplier (PMF) for all sizes equal to
2.273.

Record the information on a performance sheet (see

Fig. 7). This will provide a permanent record of the balanc-
ing information.

installation location information

box size

cooling minimum airflow (cfm) limit

cooling maximum airflow (cfm) limit

reheat (cfm) limit (if applicable)

heating minimum airflow (cfm) limit (if applicable)

heating maximum airflow (cfm) limit (if applicable)

calibration gain (after balancing)

set points

PNEUMATIC CONTROLS

Preparation for Balancing (Control Sequences
1102 and 1103)

1. Inspect all pneumatic connections to assure tight fit and

proper location.

2. Verify that the thermostat being used is compatible with

the control sequence provided (direct acting or reverse
acting).

3. Check main air pressure at the controller(s). The main air

pressure must be between 15 psi and 25 psi. (If dual or
switched-main air pressure is used, check the pressure at
both high and low settings.) The difference between
“high” pressure main and “low” pressure main should be
at least 4 psi, unless otherwise noted, and the “low” set-
ting difference should exceed 15 psi.

4. Check that the unit damper will fail to the proper position

when main air pressure is lost. Disconnect the pneumatic
actuator line from the velocity controller and observe the
VAV damper position. The damper should fail to either a
normally open position (indicator mark on shaft end is
horizontal) or a normally closed position (indicator mark
on shaft end is vertical).

5. Check that there is primary airflow in the inlet duct.
6. Connect a Magnehelic gage, inclined manometer or other

differential pressure measuring device to the balancing
taps provided in the velocity probe sensor lines. The
manometer should have a full scale reading of 0.0 to
1.0 in. wg. The high pressure signal is delivered from the
front sensor tap (away from the valve), and the low pres-
sure signal is delivered from the back line (near the
valve). The pressure differential between high and low
represents the amplified velocity pressure in the inlet
duct.

7. Read the differential pressure and enter the Linear Aver-

aging Probe Chart to determine the airflow in the terminal
unit. This chart is shown in Fig. 6 and is also attached to
the side of each unit. For example, a differential pressure
of 0.10 in. wg for a size 8 unit yields an airflow of
275 cfm.

Volume controllers for 35EP units are shown in Fig. 8-10.

Identification for each controller is shown in Table 4.

UNIT SIZE 35E

04

05

06

07

08

09

INLET

DIAMETER

4.0

5.0

6.0

7.0

8.0

9.0

AIRFLOW (Cfm)

AT 1 in. wg

232

362

502

710

927

1174

INLET AREA

(sq ft)

0.087

0.136

0.196

0.267

0.349

0.442

35E UNIT SIZE

10

12

14

16

22

INLET DIAMETER

10.0

12.0

14.0

16.0

16 x 24

AIRFLOW (Cfm)

AT 1 in. wg

1449

2086

2840

3709

7250

INLET AREA

(sq ft)

0.545

0.785

1.069

1.396

2.640

Содержание 35E

Страница 1: ... ADJUSTMENT SLIDEBAR WIRING THE CCN NETWORK COMMUNICATION SERVICE JACK PRIMARY AIR TEMPERATURE SENSOR INSTALLATION INDOOR AIR QUALITY SENSOR INSTALLATION INDOOR AIR QUALITY SENSOR WIRING HUMIDITY SENSOR Wall Mounted INSTALLATION Connect the CCN Communication Bus 19 COMMUNICATION BUS WIRE SPECIFICATIONS CONNECTION TO THE COMMUNICATION BUS Water Valve Installation 19 ComfortID Start Up 19 GENERAL PR...

Страница 2: ...ls or controls File damage claim immediately with transportation agency and notify Carrier UNIT IDENTIFICATION Each unit is supplied with a shipping label and an identification label Fig 2 INSTALLATION PRECAUTION Check that construction debris does not enter unit or ductwork Do not operate the central station air handling fan without final or construction filters in place Accumulated dust and cons...

Страница 3: ...urn tracking 4149 Proportional floating hot water with supply return tracking 4150 Return air damper CCN Thermostats Ordered Separately Thermostat 33ZCT56SPT RT room temperature sensor with set point adjust and override Thermostat 33ZCT55SPT RT room temperature sensor with override only Thermostat 33ZCT58SPT Communicating room tempera ture sensor with LCD liquid crystal diode set point adjust fan ...

Страница 4: ...ion area Remove unit from ship ping package Do not handle by controls or damper extension rod 2 The unit has factory installed brackets on unit as shown in Fig 3 3 Suspend units from building structure with straps rods or hanger wires Secure the unit and level it in each direc tion Note that reheat coil is in heavy end of unit Step 2 Make Duct Connections 1 Install supply ductwork on unit inlet co...

Страница 5: ...04 0 35 675 13 0 21 0 09 0 27 0 44 0 60 0 76 0 09 925 13 0 39 0 17 0 51 0 82 1 13 1 43 0 17 240 240 or 0 240 4 9 0 02 0 01 0 02 0 03 0 04 0 05 0 01 9 550 11 3 0 08 0 07 0 12 0 17 0 22 0 27 0 07 0 44 875 16 0 21 0 17 0 31 0 44 0 57 0 69 0 17 1200 16 0 40 0 32 0 59 0 83 1 07 1 31 0 32 300 290 or 0 300 6 2 0 02 0 01 0 02 0 04 0 05 0 07 0 01 10 675 13 9 0 08 0 04 0 12 0 20 0 27 0 35 0 04 0 55 1075 21 ...

Страница 6: ...is typical of 480V 3 phase 4 wire heater and control Refer to actual unit wiring diagram AFS Airflow Switch DDC Direct Digital Controls Fig 5 Typical Power Connections for 35E Units with 3 Stage Electric Heat ANALOG OR DDC CONTROLLER 24VAC BLU YEL CLASS II TRANSFORMER OPTIONAL 120VAC 208VAC 240VAC 277VAC L1 GROUND 24 VAC POWER LEGEND NOTE Drawing is typical refer to actual unit wiring diagram for ...

Страница 7: ...s will provide a permanent record of the balanc ing information installation location information box size cooling minimum airflow cfm limit cooling maximum airflow cfm limit reheat cfm limit if applicable heating minimum airflow cfm limit if applicable heating maximum airflow cfm limit if applicable calibration gain after balancing set points PNEUMATIC CONTROLS Preparation for Balancing Control S...

Страница 8: ...______ ENGINEER ______________________________________________ BUILDING LOCATION FLOOR ______________________________ BUS NUMBER ___________________________________________ Fig 7 Air Terminal Performance Sheet CONTROL SET POINTS Tag Number Zone Address Box Size in cfm Cooling cfm Reheat cfm Heating cfm Heat kW Occupied Unoccupied Calibration Gain min max min max Type Btu min max min max mult ...

Страница 9: ...DAMPER Control Sequence 1103 Refer to Fig 9 1 Maximum volume setting a Disconnect the thermostat line from the velocity controller b Adjust the maximum volume control knob marked HI and located in the center of the con troller to achieve the required minimum flow To determine the required pressure differential refer to Tables 2 and 5 and the Linear Averaging Probe Chart provided on the side of the...

Страница 10: ... initial adjustments are made cycle the thermostat pressure a few times to settle the internal reset mechanisms and verify set tings Fine tune the settings if necessary The thermostat pres sure may be left at a high pressure and the G port cap may be removed and replaced to cycle the reset mechanism RESET START setting is factory set at 8 0 psig This is the lowest thermostat pressure that the LO S...

Страница 11: ... heating set point slider all the way to the right for maximum heating 5 Read the DC voltage across the meter taps on the heating left side Adjust the maximum set point MAX INCR potentiometer clockwise to increase or counterclockwise to decrease to the DC voltage equal to the desired air flow cfm as shown on the calibration curve Fig 14 NOTE The maximum set point must be adjusted last Adjust ment ...

Страница 12: ...adjusted first Adjust ment of the MIN INCR potentiometer directly affects the max imum set point and auxiliary set point 2 Adjustment of auxiliary set point if required Read the DC voltage across the meter taps on the heating left side Adjust the MAX AUX INCR potentiometer clockwise to increase or counterclockwise to decrease to the DC voltage equal to the desired airflow cfm 3 Return the cooling ...

Страница 13: ... and 2 of connector J1 Refer to unit wire label diagram for minimum size VA and grounding requirements for each unit SUPPLY AIR TEMPERATURE SAT SENSOR INSTAL LATION On terminals with heat the SAT sensor is provid ed The sensor is factory wired to the controller and shipped in the control box The SAT must be field installed in the duct downstream from the air terminal The SAT sensor part num ber is...

Страница 14: ... connection will be made If connection is desired the CCN communication cable should be available at time of sensor installation for convenient wiring connections The cable selected must meet the requirements for the entire network See Connect the CCN Communication Bus section for CCN communication cable specifications RESISTANCE Ohms TEMP F RESISTANCE Ohms TEMP F RESISTANCE Ohms TEMP F RESISTANCE...

Страница 15: ...inches Fig 18 Space Temperature Sensor and Wall Mounted Humidity Sensor Mounting 2 3 4 5 6 1 SW1 SEN BLK GND RED SPT RED WHT GND BLK CCN COM SENSOR WIRING Fig 19 Space Temperature Sensor Wiring 33ZCT55SPT 2 3 4 5 6 1 SW1 SEN SET Cool Warm WHT T56 BLK GND RED SPT RED WHT GND BLK CCN COM SENSOR WIRING JUMPER TERMINALS AS SHOWN Fig 20 Space Temperature Sensor Wiring 33ZCT56SPT ...

Страница 16: ...he sensor end of the cable 3 Connect the sensor cable as follows a Connect one wire from the cable RED to the SPT terminal on the controller Connect the other end of the wire to the left terminal on the SEN ter minal block of the sensor b Connect another wire from the cable BLACK to the ground terminal on the controller Connect the other end of the wire to the remaining open termi nal on the SEN t...

Страница 17: ... the sensor where it is influenced by the supply air the sensor gives inaccurate readings if the supply air is blown directly onto the sensor To mount the sensor refer to the installation instructions shipped with the accessory kit INDOOR AIR QUALITY SENSOR WIRING To wire the sensor after it is mounted in the conditioned air space see Fig 23 25 and the instructions shipped with the sensor Use two ...

Страница 18: ...he center of the sensor 2 Connect the RED wire to the sensor screw terminal marked 3 Install one lead from the resistor supplied with the sen sor and the WHITE wire into the sensor screw terminal marked After tightening the screw terminal test the connection by pulling gently on the resistor lead 4 Connect the remaining lead from the resistor to the BLACK wire and secure using a field supplied clo...

Страница 19: ...nal zone controllers in a daisy chain fashion following the color coded wiring scheme in Table 9 NOTE The communication bus drain wires shield must be tied together at each zone controller If the communica tion bus is entirely within one building the resulting contin uous shield must be connected to ground at only one single point If the communication bus cable exits from one build ing and enters ...

Страница 20: ...s a portable device to change system set up and set points from a zone sensor or ter minal control module During start up the Building Supervisor or the Network Service Tool can also be used to verify commu nication with each controller For specific operating instructions refer to the appropriate user manual See Table 11 for troubleshooting information ComfortID TEST AND BALANCE TOOL SOFT WARE The...

Страница 21: ...n electric box mounted horizontally may be used instead of cutting the hole 2 Remove the cover from the thermostat controller Care fully remove the circuit board from the backplate of the thermostat controller Line up the backplate with the hole in the wall Push the protruding part of the backplate into the hole Pull the thermostat controller wires out through the backplate 3 Attach backplate to w...

Страница 22: ... board Slide the cir cuit board under the back plate securing bars DO NOT CREASE RIBBON CABLE 7 Align thermostat board with alignment pin Gently pull down on the thermostat latch and press firmly until the circuit board snaps into place 8 If optional locking thermostat cover is purchased insert locking clip on the inside of the thermostat cover Push firmly into place 9 Insert tabs on thermostat co...

Страница 23: ...k system Variable Volume and Temperature VVT Product Data literature and the configura tion instructions provided with the thermostat Refer to the specific control sequence 35E 82XX for de tailed operational information This information should be used to test and commission the control Control Start Up GENERAL Air volume delivery to the conditioned space is controlled by the modulating of the prim...

Страница 24: ... discontinue or change at any time specifications or designs without notice and without incurring obligations Catalog No 533 530 Printed in U S A Form 35E 2SI Pg 24 3 06 Replaces 35E 1SI Copyright 2006 Carrier Corporation Book 3 Tab 6a ...

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