UNT-IOM-6
29
The manual circuit setter valve is an optional end valve supplied on
the return pipe of the factory piping package. The valve allows the
operator to regulate water flow through the hydronic coil, balance the
water flow through the unit with other units in the piping system, and
serves as a shutoff or end valve. See Figure 17.
Follow the procedure below to set maximum water flow through the
coil.
1.
Establish water flow through the coil. Perform an open override of
the valve if the control valve is closed to the coil, either manually or
by Tracer
®
.
If the piping package has 2-position, normally closed valves:
Drive open the valve using a 24V signal.
If the piping package has 2-
position, normally open
valves:
Manually drive open the valve by
removing power to the valve.
If the piping package has
modulating valves:
To manually drive the valve open,
depress the button stem on top
of the valve and push the lever
located on the side of the valve to
the full open position.
2.
For presetting, use the appropriate valve curve shown in Figure 19
on page 30 to determine which setting is necessary to achieve the
appropriate pressure drop.
3.
Carefully remove the Schrader pressure port connection caps on
the manual circuit setter, since they will be at the same temperature
as the pipeline.
4.
Bleed all air from the hoses and meter before reading the pressure
drop. Refer to the gauge operating instructions.
5.
Adjust the circuit setter valve by turning the valve stem until the
appropriate pressure drop is achieved. See Figure 18 on page 30.
6.
After achieving the proper setting, slightly loosen the two socket
head cap screws and rotate the memory stop around until it
touches the back side of the indicator. Then tighten the screws to
Figure 17. Manual circuit setter
valve.
Balancing The Manual
Circuit Setter Valve