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CSC-3000 Series Pneumatic VAV Reset Volume Controllers 

    4 

Applications Guide, Rev G

Adjustments and Calibration

NOTE:  Do 

NOT

 

adjust

 reset start point and reset 

span 

(upper and lower knobs)

 without 

thoroughly reviewing the relevant sections.

Damper Action

The damper action is factory-set at Normally Open 

(N.O.). To change to Normally Closed (N.C.), per-

form the following steps:
1.  Loosen the damper selection screw.
2.  Turn the selection dial clockwise until the “NC” 

arrow aligns with the “DAMPER” arrow.

NOTE:  Accuracy in the alignment of the arrows is 

very important. Make this adjustment as 

exact as possible.

3.  Tighten the selection screw. 

Be sure the 

screw is tight

 (2 to 4 in-lbs. of torque), 

but if 

overtightened, the plastic will strip out.

DIRECT Reset Minimum and Maximum

Determining the Type of Reset

The following table shows when Direct Reset or 

Reverse Reset is required. Determine the reset type 

based on the temperature of the primary air entering 

the VAV box and whether the thermostat in the space 

is direct or reverse acting.

Adjusting Minimums and Maximums

When adjusting the minimum and maximum airflow 

settings, the output responds slowly to changes in 

the setpoint. Wait for the flow rate to stabilize after 

making an adjustment (usually 20 to 30 seconds) be-

fore making further adjustments. Also, if the damper 

position is all the way closed or open when starting 

this step, turn the adjustment one full turn, and then 

wait 20 to 30 seconds for a change in the flow read-

ing of the Magnehelic gauge. If no change occurs 

after this time, repeat until the flow rate changes.

NOTE:  The direct reset illustration above assumes 

no relays are connected between the 

thermostat and “T” port.

For Direct Reset (DA thermostat for cooling or RA 

thermostat for heating), perform the following steps:
1a. On the CSC-3000, disconnect the “T” port and 

leave it open. Temporarily plug the tubing (but 

do NOT plug the port).

1b. 

Alternately,

 instead of removing the tubing from the 

T port, (temporarily) remove the plug from the CSC-

3000’s “G” port.

2.  Adjust the LO STAT 

P (center dial) one 

adjustment at a time until the desired 

Minimum 

airflow is read at the Magnehelic gauge and is 

stable.

NOTE:  Adjust the dial no more than about a 

half rotation at a time. After making any 

adjustment, wait approximately ten seconds 

while watching for motion in the damper 

shaft. If no motion occurs, make the next 

adjustment.

NOTE: 

IF the LO STAT 

P Limit must be set at 

“0” (zero minimum),

 do not turn the LO 

STAT 

P knob fully clockwise. The knob 

will adjust one and one-half turns after a 

zero minimum is reached. Turning the LO 

STAT 

P knob fully clockwise will result 

in a negative reset condition. This means 

that when the controller begins to reset at 

the reset start point, it must first overcome 

the negative adjustment and will not begin 

to reset from “0” until a higher thermostat 

reset pressure is reached. This negative 

reset will also reduce the effective range 

of the controller by reducing the low end 

reset, narrowing the reset span. If a zero 

minimum is required, adjust the LO STAT 

P knob until the controller just begins to 

crack the damper open, and then back-off 

one-quarter

 turn and verify zero airflow. 

(This is typically 2-1/2 knob rotations 

counterclockwise from the fully clockwise 

position.)

Primary Air

Thermostat

Reset Type

Cooling

DA

Direct Reset

RA

Reverse Reset

Heating

DA

Reverse Reset

RA

Direct Reset

Thermostat Pressure

Max. Airflow

Min. Airflow

Reset Start Point

• 3 psig: CSC-3021/3026 
• 8 psig: CSC-3011/3016/3017/3025 
• 10 psig: CSC-3023

Reset Span (5 psig)

(Cooling w/ DA Thermstat or

Heating w/ RA Thermostat)

Содержание CSC 3000 Series

Страница 1: ... 4 REVERSE Reset Minimum and Maximum 5 Reset Start Point 6 Reset Span 6 Troubleshooting 7 Maintenance 7 Important Notices 7 Magnehelic Gauge to Airflow Rate Chart 8 Replacement Cross References 9 Applications 10 Cooling 10 Cooling with Heating Valve 11 Cooling with Heating P E Switch 12 Dual Duct 13 Dual Duct Constant Volume 14 Index 15 NOTE This Application Guide does not apply completely to the ...

Страница 2: ...w These CSC 3000 series reset volume controllers are designed for use on heating or cooling systems with normally open or normally closed VAV terminal units and direct or reverse acting thermostats They are sub master air velocity controllers Each is equipped with separate adjustment knobs for mini mum and maximum airflow setpoints Models are available with various reset start points A master cont...

Страница 3: ...ack to undamaged material and reconnect Replace the tubing if it is brittle or discolored CAUTION Pneumatic devices must be supplied with clean dry control air Any other medium e g oil or moisture contamination will cause the device to fail NOTE You can easily test for leaks with a squeeze bulb to ensure there are no leaks at the actuator diaphragm or fittings 7 Use a flow hood or tee a Magnehelic...

Страница 4: ... Direct Reset DA thermostat for cooling or RA thermostat for heating perform the following steps 1a On the CSC 3000 disconnect the T port and leave it open Temporarily plug the tubing but do NOT plug the port 1b Alternately instead of removing the tubing from the T port temporarily remove the plug from the CSC 3000 s G port 2 Adjust the LO STAT P center dial one adjustment at a time until the desi...

Страница 5: ...just the dial no more than about a half rotation at a time After making any adjustment wait approximately ten seconds while watching for motion in the damper shaft If no motion occurs make the next adjustment 3a Reconnect the thermostat tubing to the T port 3b Or reinstall the plug on the CSC 3000 s G port See Step 1b 4 Adjust the thermostat to call for minimum airflow 15 psi or more at T port 5 A...

Страница 6: ...pressure gauge to the G port requires 5 32 O D tubing 3 With a small flat blade screwdriver adjust coun terclockwise to increase clockwise to decrease the reset span control at the bottom of the con troller until pressure at the G port equals the desired reset span pressure 3 psig 8 psig 13 psig Thermostat Pressure Max Airflow Min Airflow New Reset Start Point 3 psig Old Reset Start Point 8 psig R...

Страница 7: ...stat send an adequate signal to the controller Are LO STAT and HI STAT set correctly for the thermostat action When cycled can the control ler repeat the LO STAT and HI STAT settings If the LO STAT or HI STAT must be set for 0 wc see the notes about zero minimum in DIRECT Reset Minimum and Maximum on page 4 or RE VERSE Reset Minimum and Maximum on page 5 Maintenance No routine maintenance is requi...

Страница 8: ... 09 10 15 20 25 30 40 50 80 70 60 1 0 90 CFM Flow Rate as read by sensor Differential Pressure P in Inches w c NOTE This chart is for illustration only Do not use this chart to obtain your values It is NOT intended for calibration of your Minimum and Maximum adjustments This airflow chart is an example of the charts usually affixed to the VAV box Each chart is specific for the type of flow sensor ...

Страница 9: ...ressure flow pickup needs to be replace with KMC SSS 1000 series See KMC CSC Cross Reference to Universal CSC 3000 Series chart above All Titus CSC 2000 Series controllers are the same as KMC CSC 2000 Series KMC CSC Cross Reference to Universal CSC 3000 Series Universal Replacement KMC Model Older KMC Model CSC 3011 CSC 1001 CSC 2001 CSC 2003 CSC 2007 CSC 2011 Discontinued CSC 2013 Discontinued CS...

Страница 10: ...ide Rev G Applications DA Thermostat NO or NC Damper RA Thermostat NO or NC Damper Cooling These instructions do not apply to the CSC 3014 or the CSC 3501 3505 LO STAT Min Flow HI STAT Max Flow Reset Range 8 to 13 psi LO STAT Max Flow HI STAT Min Flow Reset Range 3 to 8 psi ...

Страница 11: ...e DA Thermostat NO or NC Damper and NO Hot Water Valve RA Thermostat NO or NC Damper and NC Hot Water Valve LO STAT Min Flow HI STAT Max Flow Reset Range 8 to 13 psi Hot Water Valve NO Spring Range 3 to 8 psi LO STAT Max Flow HI STAT Min Flow Reset Range 3 to 8 psi Hot Water Valve NC Spring Range 8 to 13 psi ...

Страница 12: ...tches Stage 2 On with Decrease Stage 3 Off with Increase Stage 1 On with Decrease Stage 2 Off with Increase Stage 3 On with Decrease Stage 1 Off with Increase LO STAT Max Flow HI STAT Min Flow Reset Range 3 to 8 psi NO PE Switches RA Thermostat NO or NC Damper and NO Heating P E Switch Stage 2 On with Decrease Stage 3 Off with Increase Stage 1 On with Decrease Stage 2 Off with Increase Stage 3 On ...

Страница 13: ...Guide Rev G Dual Duct Cold Deck CSC 3011 10 Damper NC LO STAT Min Flow HI STAT Max Flow Reset 8 to 13 psi Hot Deck CSC 3021 10 Damper NO LO STAT Max Flow HI STAT Min Flow Reset 3 to 8 psi Or use a CSC 3011 10 and change the reset from 8 to 3 See Reset Start Point on page 6 ...

Страница 14: ...Controllers 14 Applications Guide Rev G Dual Duct Constant Volume Cold Deck Common Discharge CSC 3011 10 Damper NC LO STAT Constant Volume Flow Reset 8 to 13 psi Hot Deck CSC 3011 10 Damper NO LO STAT Min Flow HI STAT Max Flow Reset 13 to 8 psi ...

Страница 15: ...ns 3 Cooling 10 Cooling with Heating P E Switch 12 Cooling with Heating Valve 11 Cross References 9 CSC 3011 9 13 14 CSC 3014 2 CSC 3016 9 CSC 3021 9 13 CSC 3025 9 CSC 3026 9 CSC 3501 3505 2 D Damper Action 4 Direct Reset 4 Dual Duct 13 Dual Duct Constant Volume 14 G G Port 4 Index H HI STAT 5 6 Hot Deck 13 14 I Important Notices 7 L LO STAT 4 5 6 M Magnehelic Gauge 8 Maintenance 7 Minimums and Ma...

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