(4)
Setting The Mixing Valve To The System
Typical Installation
Install the mixing valve below the hot water tank or
heater. If this is not possible, pipe in a heat trap as
shown in Figure 1 with an approximate 27
″
drop.
Connect a tempered water return line as shown in
Figure 1. This allows flow through both ports of the
mixing valve during periods of no draw.
If a dual temperature system is used, a separate re-
circulating loop and pump are required to return high
temperature hot water to the water heater. See Figure 2.
Install an aquastat at the tempered water return pump.
Install the water heater per manufacturer’s instructions.
1. After installation be sure to flush the system thor-
oughly.
2. Make sure the hot water supply is heated to normal
design temperature.
3. Close and tag all fixtures to ensure they are not
used during this procedure.
4. Turn off the recirculating pump.
5. Create a draw on the system greater than the
minimum flow rating of the mixing valve. All open
fixtures must be tagged to ensure they are not
tampered with or used during this procedure.
6. Allow water to flow through the mixing valve until
the water temperature is stable. If necessary,
readjust the mixing valve in accordance with the
TEMPERATURE ADJUSTMENT section of the
installation manual.
7. Once the temperature is set, start the recirculating
pump and allow the system to reach set tempera-
ture.
8. Measure the water temperature at the return pump
and adjust the aquastat to shut off the pump
should the return water exceed the set point by 2
degrees F. Set the low limit switch to restart the
return pump when return water drops 5 degrees
F below the set temperature.
9. Set the balancing valve in the full open position.
10. Shut off all fixtures and ensure there is no draw
on the system. The cold inlet to the mixing valve
should be warm.
11. Allow the system to run in this condition for at
least 30 minutes.
12. In some cases, an increase in water temperature
may occur during a no draw period. If this occurs,
slowly close the balancing valve until the water
temperature is back to the original set temperature.
Figure 1
Typical Installation
When used in a single temperature
recirculating system
GuARANTEE
We guarantee the Lawler Mixing Valve to be free from
def ects in workmanship and material, and for a pe-
riod of one year from date of purchase, will replace
any parts found by us to be defective. We will not be
held responsible, however, for any labor incidental
to, or for any damages caused by defective mate-
rial. Each mixing valve is thoroughly inspected and
tested under actual conditions at our factory.
Typical Installation
When used in a dual temperature
recirculating system
Figure 2
Water
Heater
Storage
Tank
Check Valve (TYP.)
To Low Temperature
Fixtures
Series 66
CW
Balancing Valve (TYP.)
Recirculating Pump
C
A
B
D
Aquastat
TS
Heat Trap
27
″
Drop
Water
Heater
Storage
Tank
Check Valve (TYP.)
To Low Temperature
Fixtures
To High Temperature
Fixtures
Series 66
CW
Balancing Valve (TYP.)
Recirculating Pumps
A
B
C
D
Aquastat
TS
E
Heat Trap
27
″
Drop
IMM000601
