Powers 744 User Manual
Technical Instructions
!
WARNING
Read this Manual BEFORE using this equipment.
Failure to read and follow all safety and use information can result in death, serious personal injury,
property damage, or damage to the equipment.
Keep this Manual for future reference.
WARNING
!
FAILURE TO COMPLY WITH PROPER INSTALLATION AND
MAINTENANCE INSTRUCTIONS COULD CONTRIBUTE TO THE
VALVE FAILURE.
This Hot Water Master Tempering Valves cannot be used for
tempering water temperature at fixtures. Severe bodily injury
(i.e., scalding or chilling) and/or death may result depending
upon system water pressure changes and/or supply water
temperature changes. ASSE standard 1016, 1069 or 1070 listed
devices should be used at fixtures to prevent possible injury.
These Hot Water Tempering Valves are designed to be
installed at or near the boiler or water heater. They are not
designed to compensate for system pressure fluctuations and
should not be used where ASSE standard 1016, 1069 or 1070
devices are required. These valves should never be used to
provide “anti-scald” or “anti-chill” service.
The components of the system must be of materials with a
construction capable of withstanding the high limit output temperatures of the water heating source.
AIR OPERATED:
Rigid Stainless Bulb
Direct Action 744-1270
Reverse Action 744-1271
Rigid Copper Bulb
Direct Action 744-1213
Reverse Action 744-1214
Specifications n
IS-P-TC744-1
Accritem Controller
Model 3
WATER OPERATED:
Rigid Stainless Bulb
Direct Action 744-1217
Reverse Action 744-1218
!
WARNING
Need for Periodic Inspection and Yearly Maintenance:
Periodic inspection and yearly maintenance by a licensed contractor is required. Corrosive water conditions and/or unauthorized adjustments or repair could render the valve ineffective for
service intended. Regular checking and cleaning of the valve’s
internal components and check stops helps assure maximum
life and proper product function. Frequency of cleaning and
inspection depends upon local water conditions.
!
WARNING
You are required to consult the local building and plumbing
codes prior to installation. If the information in this manual is
not consistent with local building or plumbing codes, the local
codes should be followed. Inquire with governing authorities for
additional local requirements.
!
WARNING
Flush all pipes thoroughly before installation. Installation and
field adjustment are the responsibility of the installer.
Operation .................................... Direct or Reverse Acting
Adjustment Dial Range—Standard 50 to 350°F (10 to 177°C)
Maximum Supply Pressure (air or water)
at Room Temperature
Air Consumption (max.)
Maximum Operating Pressure
Maximum Operating Temperature
Temperature Response
Mounting
....................................................... 1/2" NPT
Air or Water Connections
Drain Connection (water only)
Shipping Weight
.......................................... 4 lbs. (1.8 kg)
Sensitivity (adjustable)
..........................35 psi (241.3 kPa)
......................... 218 cm 3/s (800 SCIM)
...................... 1724 kPa (250 psi)
........................400°F(204°C)
................................... 0.5°F(0.3°C )
..................................... 1/8" NPT
................................ 1/4" NPT
................................3.1 to 27.9 kPa/C
(1/4 to 2-1/4 psi/F)
Maximum Pressure on Wells
Stainless Steel no. 744-082
Copper no. 744-111
Well Dimensions
............................................ See page 6
.................. 1125 psi (7756 kPa)
............................ 525 psi (3619 kPa)
Operation Instructions n
Direct Action Controller
A temperature change in the medium being controlled creates a
change in length of the sensitive tube
ture lengthens the sensitive tube
away from the lever
2
3.
The lever
A, is moved to open the exhaust valve
1
. An increase in tempera-
1
and moves the Invar rod
3
, which pivots at Point
4
by spring
5
. This
permits the supply (air or water) (S) to increase the pressure in the
control line (R) and close the normally-open valve. A decrease in
temperature shortens the sensitive tube
rod against the lever
sure spring
to open the exhaust valve
5,
3.
The lever
3
nd moves the Invar
1 a
moves against the pres-
This exhausts the
4.
pressure in the control line and opens the valve.
The sensitivity adjustment screw
regulates the rate of flow
6
of the supply air (or water) to the controller to a change in temperature. Turning the screw clockwise increases the sensitivity
by reducing the flow and increasing the response time. Turning
the screw counterclockwise decreases the sensitivity by
increasing the flow and reducing the response time.
Also see Figure 8 on page 7.
Sensitivity n
The sensitivity of the Accritem controller is adjusted by turning the restriction screw (Figure 2). (The restriction screw is
factory-set for air operation.) For water operation, the restriction
screw should be opened a minimum of 1/2 turn and controller
recalibrated. Restriction screw must never be fully closed. Make
Figure 1
Positions “B” and “D” (dotted) show
pivot point (“B”) and spring when
controller is REVERSE acting.
Positions “A” and “C” (solid) show pivot
point (“A”) and spring when controller is
DIRECT acting.
3
C
Exhaust Air
A
B
D
5
6
R
4
S
Flowrite Valve
(Normally Open)
2 1
Tank
adjustments slowly, allowing about two (2) minutes after each
adjustment for the controller to balance.
NOTICE
If sensitivity is changed, controller must be recalibrated.
Calibration n
Figure 2
Loosen set screw and turn adjusting knob to indicate
temperature at bulb. Tighten set screw. Set controller for
desired control temperature.
Figure 4
Figure 3
Turn adjusting knob until 52 kPa (7-1/2 psi) control pressure shows on gauge. Read temperature at bulb with
an accurate thermometer.
Set restriction screw for desired sensitivity. Air: 1/8 turn
from closed (minimum). Water: 1/2 turn from closed
(minimum).
2
Installation Instructions n
General Instructions
Figure 5.
To disassemble and replace sensitive tube assembly:
The Accritem Controller requires a clean, reliable supply
of compressed air or cold water at room temperature and
15 tgo 20 pounds of pressure. Other fluids may be used,
such as gas, oil, etc., providing provision is made for safe
disposal.
Select sensitive element location with care to insure satisfactory results. Bulb must project entirely into the liquid or air being
controlled.
Flush or blow out all lines before making final connections. Put
supply pressure through all control lines and check for leaks.
INSTALLATION FOR AIR OPERATION
Controller should normally be installed in horizontal position;
however, other positions may be used if the supply and control
connections are parallel with the ground and calibration is
checked after installation.
INSTALLATION FOR WATER OPERATION
Controller should normally be installed in horizontal position with
drain connection at bottom. For positive drainage at all times,
drain piping should be 3/8" minimum.
TO CHANGE CONTROLLER ACTION
(See Figures 6 and 7)
1. Turn adjusting knob clockwise to remove tension.
2. Remove adjusting knob and cover.
3. Remover lever spring retainer (D) and spring (E).
4. Relocate lever pivots (F).
5. Turn lever pivots to be snug without binding.
6. Replace lever spring retainer (D) and spring (E).
7. Replace cover and adjusting knob.
8. Recalibrate.
Figure 6
Lever
Lever
Spring
Retainer
Screw
7
8
9
DIRECT ACTING
SPRING LOCATION (in front of lever)
Spring
Retainer
Screw
The parts in Figure 7 are identified by letter in order of disassembly. For item number reference, see Parts Drawing: A (item
3) adjusting knob with set screw, B (item 10) cover screws, C
(item 2) cover plate, D (item 8) spring retainer screw, E (item 9)
lever spring, F (item 21) lever pivot, G (item 7) lever.
Always locate the controller as close as possible to the
controlled device. The piping between the controller and
controlled device (valve or damper motor) should be 1/8"
NPT brass pipe or 6.4 mm (1/4") OD copper tubing.
Difference in height between Accritem controller and controlled device should be kept to a minimum. When controller
is below controlled device, elevation cannot exceed 3 m (10")
with 104 kPa (15 psi) supply pressure. If controller is above
controlled device, adjust springs on valve or damper motor to
compensate for static head pressure.
7
8
9
REVERSE ACTING
SPRING LOCATION (behind lever)
Pressure Controller for Use with Water
Set pressure at 104–138 kPa (15–20 psi) when water is flowing.
Clean strainer at regular intervals.
Both Air and Water Controllers
To disassemble (Refer to Parts Drawing and Figure 5):
1. Remove knob 3after loosening its set screw.
2. Remove cover plate
2
.
3. Remove spring retainer screw 8and lever spring 9.
4. Back out one lever pivot 20and remove lever 7.
5. Unscrew sensitive tube assembly 20from body1.
3
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