tekmar 721 4-Way Mixing Valve - Manual

1 of 2 © 2011 D 721 - 09/11
D 721
09/11
- Data Brochure
4-Way Mixing Valve 721
The 4-Way Brass Mixing Valve 721 is used to mix supply water from a heat source with water
returning from a system. It is designed for use in either closed loop or open loop hydronic systems.
It connects to pipe using standard female NPT threads. The valve provides a maximum leak
through rate of 1% to allow for water expansion during temperature changes. The valve position
can be manually set using the handle. An Actuating Motor 741 can be used to automatically
operate the valve.
Sequence of Operation
When the flap is in the fully closed position,
100% of the boiler supply water is returned
to the boiler and 100% of the heating system
return water is supplied to the system. When
the valve flap is in the fully open position,
100% of the boiler supply water enters the
heating system and 100% of the heating
system return water returns to the boiler.
Mixing of the water takes place when the valve
flap is in an intermediate position.
Installation
Check the contents of the package. If any of the items listed below are missing or damaged, please refer to the Limited Warranty
and Product Return Procedure on the back of this brochure and contact your wholesaler or local tekmar representative.
• One Mixing Valve & One Data Brochure D 721
IMPORTANT: When mounting the valve, leave a minimum of 4” (10 cm) clearance between the bottom cover and surroundings.
This will ensure that all valve components can be easily serviced.
Replacement Parts
The Mixing Valve Handle Kit M3047 contains a replacement
manual valve handle, a brass screw, a “C” clip, and a position
indicator plate.
The Replacement O-Ring kit contains a small, a medium and
a large o-ring. Use M3056 kit for valves 3/4” to 1-1/4”.
brass
screw
handle
“C” clip
indicator plate
Valve 50% position Valve fully open Valve in closed position
As delivered, no
changes required.
Remove the “C” clip from the
shaft. Turn over the indicator
plate in order to reverse the
scale. Re-install the indicator
plate, “C” clip and handle.
(components shown below)
Valve
Closed Valve
Closed
Clockwise to Open Counter Clockwise to Open
to system
to boiler
from
boiler
5 7 9
10 3 1
0
from
system
5 3 1
0
7 9
10
to system
to boiler
from
boiler
from
system