User Manual

DESCRIPTION
The Powers 430 Hi/Lo Supply Fixture is a pre-piped system
consisting of two thermostatic valves and a PRV, designed
to provide consistent temperature control over a wide range
of flow requirements.
The unit includes: A Powers Series 430 thermostatic mixing
valve, a Powers Series 420 or 427 thermostatic mixing valve,
a Pressure Reducing Valve (PRV), pressure gauges, union
inlet strainer checkstops, dial thermometer, shut-off ball
valve, and interconnecting piping.
All components are pre-assembled for easy installation. The
stainless steel or durable white baked enamel steel cabinets
are designed for recessed or wall mount installation and pro-
vide protected access to the system.
OPERATION
This two valve supply fixture has a low capacity valve
that works in parallel with a high capacity valve.
During low demand, the low capacity valve will han-
dle the load requirements. As the load demand is
increased, the pressure reducing valve, which is set
at a certain pressure differential, will open and allow
flow through the high capacity valve to assist the low
capacity valve in meeting the load requirements.
APPLICATION
This is a typical application of the Hi/Lo Supply
Fixture for recirculation. Basic guidelines for
recirculating are provided below. Following
these guidelines will ensure stable
control of the domestic water
system during normal and
low/no use periods. Improper
piping causes the recirculat-
ing system to have erratic
pressure and temperature
fluctuations.
For Capacity requirements,
Refer to Form #MV430-3.5 or
the Hi/Lo Supply Fixture Brochure.
• DO NOT recirculate low temperature hot water (LTHW)
and high temperature hot water (HTHW) with one pump;
return water may come back hotter than mixer set point.
• To minimize natural heat convection, locate master
mixer below hot water source, or install mixer with heat
trap (a two-foot drop in the pipe line) as shown.
• Do use two (2) circulating pumps. Use check valves to
prevent reverse flow.
• Always use an Aquastat set at a temperature below set
point of mixer.
• Be certain HTHW cannot be introduced into cold side of
mixer.
• Always tie LTHW return to cold water side of mixing
valve, as well as back to hot water source.
WARNING
DO NOT OMIT THE LTHW CONNECTIONS; scalding and
severe personal injury may result from return supply
temperatures approaching hot water heater tempera-
tures.
WATER
HEATER
STEAM
INPUT
PRV
HTHW
HTHW RETURN
CW
HEAT TRAP
LTHW
RETURN
LTHW
AQUASTAT
PUMP
Hi
AQUASTAT
PUMP
Supply Pressure
Gauge
Outlet Pressure
Gauge
B a ll V alv e
B a ll V alv e
Checkstops
Checkstops
Lo
EXPANSION
TANK
Sensor
Shock Absorber
S ole n oid V a lve
(O p tio n a l)
2
qua
entry
A
S
uality…Our CommitmentQ
qua
entry
A
S
SERIES 460 ALARM
°F
TEST
Set
Reset
TECHNICAL INSTRUCTIONS
HI/LO SUPPLY FIXTURE SYSTEM
Operation, Testing, Maintenance
TI430-420