Utica Boilers H2OI Dual Manuel De Montage

Hot Water Recirculation for Solar Hot Water Storage Tanks
Hot water recirculation is for the continuous circulation of hot water for 

instant hot water at the hot water faucets. Solar tank tappings provide 

hot water recirculation return at the distance mid-height at the side of 

the tank. See Figure 8. Location of tapping will not allow for mixing of 

back-up heated hot water (boiler indirect of electric element) into lower 

solar heated section of the tank.
When an anti-scald device is installed it is critical to feed cold supply of 

mixing valve with return of recirculated hot water. This is important to 

keep hot water recirculation loop operating through the mixing valve 

even if tank temperatures are above mixing valve setting.  Other wise 

the mixing valve will not allow flow of hot water though it and disable 

recirculation loop of hot water.

Water heated to temperature for 

clothes washing, dish washing and 

other sanitizing needs can scald and 

cause permanent injury.

Children, elderly, and infirm or 

physically handicapped persons are 

more likely to be permanently injured 

by hot water. Never leave them 

unattended in bathtub or shower. Never 

allow small children to use a hot water 

tap or draw their own bath.
•  If anyone using hot water in the 

building fits the above description, 

or if state laws or local codes 

require certain water temperatures 

at hot water taps, you must take 

special precautions:

•  Use lowest possible temperature 

setting.

•  Install some type of 

tempering device, such as an 

automatic mixing valve, at 

hot water tap or water heater. 

Automatic mixing valve must 

be selected and installed 

according to manufacturer's 

recommendations and 

instructions.

Water passing out of drain valves may 

be extremely hot. To avoid injury:
•  Make sure all connections are tight.
•  Direct water flow away from any 

person.

Pipe Relief Valve 

Discharge to within 

6" of floor, see 

Section III Notes.

FIGURE 8