Trane UniTrane FC, Installation & Operation Manual

Page: 33 / 80

UNT-SVX07A-EN 33
mechanical
requirements
Installation
Balancing The Manual Circuit Setter
Valve
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 I-MR-8.
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 two-position,
normally closed valves: Drive open the
valve using a 24V signal.
If the piping package has two-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 Chart I-MR-1 on
page 34 to determine which setting is
necessary to achieve the appropriate
pressure drop. The “M” line is the
appropriate line.
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.
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
securely set the open memory position.
The memory stop indicates the last set
open position.
7. If using a three-way valve: close the
control valve to the coil, with the
differential pressure meter still
connected. This will divert flow to the
bypass side of a three-way valve.
Adjust the balancing fitting to obtain the
same pressure drop across the circuit
setter valve as in step two when the
control valve was open to the coil.
Figure I-MR-9. Automatic circuit setter valve
Figure I-MR-8. Manual circuit setter valve
Figure I-MR-10. Automatic circuit setter
valve