Armstrong FLO-RITE-TEMP - Option #3; Option #4

5
October 31, 2002 @ 3:15 pm
Option #3 A temperature switch installed well downstream of the Flo-Rite-Temp outlet on a non-recirculated
system or just into the outgoing recirculated system loop on a recirculated system, with a set point 15-30
degrees above that of the FLO-RITE-TEMP will help prevent the chance of overheated water reaching the
faucets in the event of system problems. This switch can be used to turn off the steam supply to the heater in
the event of overheating. The most economical way to accomplish this is with a solenoid on the PRV. A full
ported motorized valve on the steam supply line may also be used. Option 3B. Along these same lines, a
pressure switch installed in the inlet water line would shut down the supply steam on the heat exchanger in the
event of water pressure loss, preventing thermal shock and water hammer to the unit.
Option #3Option #2
Loop or System
Thermometer
3-Way
Thermostatic
Valve
Cold Water Supply to
Flo-Rite-Temp
Temperature
Switch
Loop or System
Thermometer
Cold Water Supply
To Flo-Rite-Temp
Option 3A
Option 3B
Pressure Switch
!
To steam
shut-off valve
Hot Water Supply From
Flo-Rite-Temp
To Steam
Shut-Off Valve
Option #4 (Available only when a pressure reducing station is installed on the Flo-Rite-Temp). Using the
Model GP-2000W1P system, when piped as shown in the Option 4 drawing, will provide a safe dependable
shut down of the main steam valve when the water pressure fails or drops rapidly on the Flo-Rite-Temp.
Unlike a solenoid application, which shuts the steam down when the water pressure drops below a pre-set
point, the GP-2000W1P offers another benefit that it allows the system to keep producing hot water even
when the water pressure is below the set pressure. The GP-2000W1P Combination valve essentially lets the
steam pressure modulate below the water pressure by 2 or 3 pounds, allowing a water heater to supply hot
water even when water pressure is low.
Incoming cold water is piped into the hot water heater with a sample line piped to the W-1 Pilot of
GP-2000W1P. At the same time the cold water is supplying the water heater, its pressure it is also supplying
the W-1 Pilot. When the pressure of the incoming cold water decreases, the W-1 Pilot modulates down the
supply of steam to the pressure pilot controlling the main steam valve, acting as a non-electric self-controlled
shutdown device. Ultimately, this valve eliminates the use of any electricity and gives the customer safe
control of their hot water supply when water pressure loss or fluctuating water pressure conditions exist.
Hot Water from
Flo-Rite-Temp
Option #4