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CSC-3000 Series Pneumatic VAV Reset Volume Controllers 

    6 

Applications Guide, Rev G

Reset Span

NOTE:  In almost all applications, the reset span 

never needs adjusting. Do not change the 

default 5 psi unless really necessary.

The reset span is the thermostat’s effective reset 

range for the controller. A reset span of 5 psi means 

that it will take a 5 psi pressure change measured 

from the reset start point to reset the flow rate of the 

VAV box.

3 psig

8 psig

13 psig

Thermostat Pressure

Max. Airflow

Min. Airflow

Reset Start Point (8 psig)

Reset Span (5 psig)

NOTE:  Reset span is the pressure change at “T” 

above the reset start point that causes the 

flow setpoint to move from one extreme to 

the other. In a direct reset application, the 

flow setpoint will change from minimum 

to maximum flow above the start point. In 

a reverse reset application, the reset will 

change from maximum to minimum flow 

above the start point.

The CSC-3000 series are factory set with a reset span 

of 5 psi. This is standard in most applications and 

does not typically require adjustment. Leaving this 

adjustment at the factory setting is recommended.
If necessary, the reset span can be adjusted (between 

0 and 10 psi). If the reset span is changed, the 

minimum and maximum flows may need to be 

readjusted.
To adjust the reset span to another value, perform the 

following steps:
1.  Adjust the thermostat to a higher pressure, 

beyond working range (20 psi is best).

2.  Attach a 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)

(Reverse) Reset Start Point Adjusted from 8 to 3 psi

Reset Start Point

The reset start point is the pressure from the 

thermostat at which the controller begins to reset 

from the LO STAT to the HI STAT setting.
Models of the CSC-3000 series come with reset 

start points factory-set at 3, 8, or 10 psi. (See the 

chart on the next page.) These are standard in most 

applications and typically do not require adjustment. 
If a reset start point is needed other than the default 

setting, all models are field adjustable between 0 and 

10 psi. (If the reset start point is changed, the reset 

span may need to be adjusted as well.) To adjust the 

reset start point, carry out the following steps:
1.  Put the thermostat pressure at the desired start 

point pressure (e.g., 3 psi).

2.  Remove rubber plug at the “G” port and read 

pressure at “G” with a 0–30 psi gauge (requires 

5/32" O.D. tubing).

3.  With a small flat-blade screwdriver, adjust 

(counterclockwise to increase; clockwise to 

decrease) the reset start point control (at the top 

of the controller) until the pressure read at “G” 

port is just beginning to move off zero (0) psi.

NOTE:  If the controller does not respond correctly 

after all adjustments have been made, it 

may be necessary to correct the reset span 

adjustment.

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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