AERCO Electronic Control Valve User Manual
Instruction
VA-115
No.
AERCO INTERNATIONAL, Inc., Northvale, New Jersey 07647 USA
Installation, Operation
& Maintenance Instructions
ELECTRONIC
CONTROL VALVE
Type CXT-E
Printed in U.S.A. REVISED 4/18/07
Telephone Support
Direct to AERCO Technical Support
(8 to 5 pm EST, Monday through Friday)
(800) 526-0288
AERCO International, Inc.
159 Paris Avenue
Northvale, NJ 07647
www.aerco.com
© AERCO International, Inc., 2006
The information contained in this
installation, operation and maintenance
manual is subject to change without
notice from AERCO International, Inc.
AERCO makes no warranty of any kind
with respect to this material, including
but not limited to implied warranties of
merchantability and fitness for a particular application. AERCO International is
not liable for errors appearing in this
manual.
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
TABLE OF CONTENTS
SECTION PAGE
SAFETY PRECAUTIONS iii
1 - GENERAL INFORMATION 1-1
2 - INSTALLATION 2-1
3 - ADJUSTMENT 3-1
4 - OPERATION 4-1
5 - FUNCTIONAL DESCRIPTION 5-1
6 - ROUTINE MAINTENANCE 6-1
7 - TROUBLESHOOTING 7-1
8 - CORRECTIVE MAINTENANCE 8-1
9 - RECOMMENDED SPARES
9-1
i
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
LIST OF ILLUSTRATIONS
FIGURE TITLE PAGE
1-1 Reference Dimensions for AERCO Control Valves, Type CXT-E 1-2
2-1 Recommended Control Valve, CXT-E Installation For Steam Flow 2-3
2-2 Recommended Control Valve, CXT-E Installation For Hot (Boiler)
Water Flow
3-1 Actuator Adjustment 3-2
5-1 Electronic Control Valve, Type CXT-E 5-1
6-1 Valve Shaft Seals 6-1
8-1 Valve Assemblies, Type CXT-E (Sizes 1.00” To 2.00”) 8-6
8-2 Valve Assemblies, Type CXT-E (Sizes 2.50” To 4.00”) 8-8
8-3 Cage Removal Tool 8-10
8-4 Linkage Assembly Installation Details 8-11
8-5 Actuator Replacement 8-13
8-6 Linkage Assemblies 8-14
2-3
ii
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
SAFETY PRECAUTIONS
Installing or operating personnel must, at all times, observe all safety regulations.
The following warnings are general and must be given the same attention as
specific precautions included in the instructions
WARNING!
FLUIDS UNDER PRESSURE MAY CAUSE INJURY TO
PERSONNEL OR DAMAGE TO EQUIPMENT WHEN
RELEASED
CLOSE ALL SHUTOFF VALVES AND CAREFULLY
TRAPPED PRESSURES TO ZERO BEFORE PERFORMING ANY
MAINTENANCE. TAG THE PRESSURE SOURCE “OUT OF SERVICE” WHILE
PERFORMING MAINTENANCE TASKS.
DECREASE ALL
WARNING!
LIVE STEAM CAN CAUSE SEVERE BURNS
NEVER SEARCH FOR LEAKAGE IN A LIVE STEAM SYSTEM BY “FEEL”. USE
A MIRROR OR OTHER SUITABLE POLISHED OBJECT.
iii
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
1 - GENERAL INFORMATION
INTRODUCTION
This Instruction Manual provides installation, adjustment, operation and maintenance procedures for the
AERCO Electronic Control Valves, Type CXT-E. These Valves can be used for either steam flow or hot
(boiler) water flow applications.
If an AERCO Electronic Control System (ECS) is also included with the shipment, refer to AERCO
Instruction Manual AC-105. In addition to providing full coverage for the ECS, Instruction Manual AC-105
also includes all descriptions and procedures contained in this manual (VA-115).
ELECTRONIC CONTROL VALVE, TYPE CXT-E
Each Electronic Control Valve is comprised of three major sections; the Valve Body, the Linkage
Assembly and the Valve Actuator. The Control Valves are available in sizes ranging from 1 inch to 4
inches. An identical Actuator Assembly is used with each size Valve Body. The Linkage Assembly used
with each size Valve Body is identical, except for minor differences in the Shaft Adapter stroke of the
mechanical linkage. Figure 1-1 shows the basic dimensions for each size AERCO Electronic Control
Valve, Type CXT-E.
It should be noted that the Control Valves used for steam flow are identical to those used for hot (boiler)
water flow.
CONTROL VALVE ACCESSORIES
The accessories required for use with AERCO Electronic Control Valves, Type CXT-E will depend on the
specific application. Detailed installation instructions, including typical installation drawings are provided in
the INSTALLATION Section of this manual. However, please note the items listed below and ensure that
ALL mandatory items are available:
ACCESSORY
• Upstream Shutoff Valve
• Downstream Shutoff Valve
• Strainer and Blow-Off Valve
• High Side Pressure Gauge
• Low Side Pressure Gauge,
Compound Type for steam flow
If any of the above items have been furnished by AERCO with the CXT-E Control Valve, the necessary
drawings and/or instructions should be included with the shipment.
REQUIREMENT
- Mandatory
Suggested for ease of maintenance.
Required if a Bypass Line is used.
Mandatory
Recommended for adjustment and
maintenance
Recommended for adjustment and
maintenance.
1-1
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
Figure 1-1. Reference Dimensions for AERCO Electronic Control Valves, Type CXT-E
1-2
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
2 - INSTALLATION
INTRODUCTION
The installation procedures contained in this section apply to all sizes of AERCO Electronic Control
Valves, Type CXT-E, ranging from 1 inch to 4 inches. These procedures can be used for both steam and
hot (boiler) water flow systems.
ELECTRONIC CONTROL VALVE TYPE CXT-E INSTALLATION
Basically, the installation procedures for the Electronic Control Valve consist of:
• Installing the CXT-E Electronic Control Valve and associated steam or hot (boiler) water piping and
components.
• Connecting external electrical power and control signals to the Control Valve Actuator
Proceed as follows:
1. Refer to Figure 1-1 for dimensions of the Control Valve furnished with the Packaged Water Heater.
2. Next, refer to the recommended installation drawing in Figure 2-1 for steam flow, or Figure 2-2 for hot
(boiler) water flow.
3. Install the Control Valve with the Actuator Linkage in the vertical, upright position as shown in Figure
2-1 or 2-2.
4. For maintenance purposes, unions are required with threaded ends to simplify removal from the
steam or hot boiler water line.
5. Blow out all pipe lines to clear them of dirt chips, scale or other foreign matter which could adversely
affect Valve operation when in service.
6. Install an in-line strainer upstream of the Valve as shown in Figure 2-1 (steam) or Figure 2-2 (hot
boiler water). This will protect against foreign matter reaching the Valve during service operation.
7. If the Valve is controlling steam, ensure that the steam line is properly trapped to prevent
accumulation of condensate ahead of the Valve.
8. Install Shutoff Valves (metal-seated, gate-type) upstream and downstream of the Control Valve to
permit removal from the line for maintenance.
9. Pressure gauges should be installed on both sides of the Control Valve as shown in Figure 2-1
(steam) or Figure 2-2 (hot water).
2-1
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
10. The gauge on the high pressure side of the Valve is for adjustment and maintenance purposes. The
gauge on the low pressure side is to ensure that the correct pressure is being introduced to the
Control Valve. For either steam or water flow, the low side gauge denotes the pressure of the fluid in
the line which may create a hazardous condition.
11. A temperature gauge should be installed in the high pressure side of a hot (boiler) water line as
shown in Figure 2-2.
CAUTION
DO NOT use the Actuator Linkage Frame at the top of the Control Valve Body for
leverage when installing the Control Valve. Use pipe wrenches on the inlet and
outlet hex of the Valve Body.
12. Install the Control Valve with the arrow on the Valve Body pointing in the direction of flow.
13. After the Control Valve has been installed in the steam or hot water line, ensure that all piping
connections are secure and leak tight..
14. If the Electronic Control Valve Type CXT-E is furnished separately, without an AERCO Electronic
Control System (ECS), electrical power and control signal connections must be made at the 3-pin
Molex connector as follows:
Pin 1 COMMON
Pin 2 +24 VDC
Pin 3 4–to-20 mA Control Signal
This completes the installation procedures for Control Valves shipped separately.
2-2
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
WATER
SOURCE
Figure 2-1. Recommended Control Valve, CXT-E Installation For Steam Flow
AERCO TYPE CXT-E
FROM
UPSTREAM
SHUTOFF
VALVE
STRAINER
BLOW-OFF VALVE
TEMPERATURE
GAUGE
HIGH SIDE
PRESSURE
GAUGE
CONTROL VALVE
PIPE UNIONS NOT
REQUIRED WHEN
VALVE IS FLANGED
DOWNSTREAM
SHUTOFF VALVE
LOW SIDE
PRESSURE
GAUGE
TO HEATER
(PIPING AS SHORT
AS POSSIBLE)
Figure 2-2. Recommended Control Valve, CXT-E Installation For Hot (Boiler) Water Flow
2-3
VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
3 - ADJUSTMENT
INTRODUCTION
Place the AERCO Heater (or other equipment being controlled) into operation in accordance with the
instructions furnished with the Heater (or other equipment).
WARNING
The Upstream Steam or Boiler Water Shutoff Valves MUST be closed prior to
performing the following adjustment procedures. Failure to observe this
WARNING may result in personal injury.
CONTROL VALVE TYPE CXT-E ADJUSTMENT
All CXT-E Actuators are powered by 24 VDC and are controlled by a linear 4-to-20 mA control signal. A 4
mA control signal input places the Control Valve in the fully-closed position; while a 20 mA signal strokes
the Valve to the fully-open position.
The Control Valve Actuators are self-calibrating for all Valve sizes. Therefore, simply proceed as follows
to automatically adjust the Actuator:
NOTE
The following adjustment procedure must be performed any time that the CXT-E Actuator
is replaced or a mechanical adjustment is made to the Linkage Assembly or Valve.
1. Refer to Figure 3-1 and loosen the Actuator cover set screw.
2. Remove the Actuator cover to access the PC Board containing the terminal connections, DIP
switches, Auto-Stroke (Reset) button and LED shown in Figure 3-1.
NOTE
If the Control Valve is furnished with an AERCO Electronic Control System (ECS), power
is applied to the Valve Actuator when the Control Box POWER switch is set to ON.
3. Apply 24 VDC power across Actuator pins 2 (+) and 1 (Common). The LED will light indicating that
power is applied. Wait approximately 10 seconds while the unit performs a self-test. Upon successful
completion of the self-test, the LED will blink 3 times and then go off.
4. For full-stroke automatic adjustment, press the Auto-Stroke (Reset) button. The LED will light.
5. The Actuator will then rotate in both directions to find its open and closed Valve position stops.
6. Upon successful completion of the automatic adjustment, the LED will blink 3 times and then go off..
7. Turn off power to the Actuator. Replace and secure the cover by tightening the set screw.
3-1
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