LAARS Mighty Therm IW (Sizes 500-1825) - Installation, Operation and Maintenance Instructions - Manual (Page 12)

LAARS Heating Systems
Page 12
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.
Figure 13. Split System Piping Diagram, Model IW.
Figure 12. Hot Water Supply System Using Model PW with Dual Tanks, Building Loop Return and Circulating Pump.