Hot Water Supply System Using Model Pw With Dual Tanks, Building Loop Return And Circulating Pump; Water Heaters - Natco VW Installation And Operating Instructions Manual

Return
Loop
Pump
(see note 2)
Service Valve
NOTES:
1. Heavy line indicates Heater to Tank Circulating Loop.
2. When a very large volume of water is circulated in the building loop with the use of a separate pump, tee building loop into cold water
supply and return to storage tank.
Figure 12 –Hot Water Supply System Using Model PW with Dual Tanks, Building Loop Return and Circulating Pump
Flow Switch -
Factory Mounted
and Wired
Gas Supply
Model IW
Water Heater
Building Loop
Circulator
(See Note 3)
CAUTION:
1. This piping arrangement is required on split systems to provide constant hot water temperatures.
2. Pipe size and length must conform to the recommendations for each heater model.
3. A loop circulator is required to maintain forced circulation in the building hot water piping system.
Hot Water
Hot Water
Return
To Building
From
Building
Service Valve
Check
Valve
Conventional
Tank
Pressure
Relief
Valve
To Drain
Drain Valve
Figure 13 – Split System Piping Diagram, Model IW
Conventional
Tank
Cold
Water
Supply
To Drain
Service Valves
Pressure
Relief
Valve
Building Loop
Circulator
(See Note 3)
Service Valves For
*Heater Isolation
Check Valve
12
To Drain
Recommended Increasing
One Pipe Size From C.W.
Connection To Tanks
Optional Cold Water Supply
When Adequate Tank Opening
Not Available
Building Loop
Minimum
Pipe Size
1" Thru 850
1-1/4" 1010 Thru 1825
Check Valve
Cold Water
Supply
To Building Service
Connections
*This Section Of Piping Must Be Same
Size As Water Heater Connection