Noritz NR111-SV Manuel D'installation page 50

11.
Plumbing Applications
NORITZ
Tankless Gas
Water Heater
Isolation
Kit(*4)
Relay for Pump
(if larger than 85 Watts)
Hot Water
Combination Potable Water and Space Heating System
NORITZ
Tankless Gas
Water Heater
Isolation
Kit(*1)
50
Recirculation System
Cold Water Supply
Fixtures
Expansion Tank
(Install according
to local code)
Gas Supply
Globe
Aquastat(*3)
Valve
Pump Control Signal(*2)
Optional 8-10 Gallon
Storage Tank
(To alleviate cold water sandwich)
Pump(*2)
Check
Valve(*3)
Gas Supply
Hot Water
Hot Water Return
Pump(*1)
Air Handler
Flow Switch(*4)
Optional
Expansion Tank(*6)
Mixing Valve(*5)
Notes:
1. Size the pump to provide a maximum of 2 GPM
through the system at 10 ft of head plus piping
losses.
Adjust the flow using a globe valve and verify the
flow rate with the maintenance monitors.
2. Pump Control Signal is the preferred method
to control the recirculation pump.
For pumps larger than 85W, a relay connection must
be used. If the Pump Control Signal is not used,
an Aquastat may be used to control the pump.
3. Use an Aquastat if the water heater is not control-
ling the pump.
Set the Aquastat to 10°F below the set output
temperature.
4. Noritz recommends the use of an Isolation Kit
with the installation.
These kits include an integrated shut-off and serv-
ice valve with unions and a pressure relief valve.
Pump
120VAC
Neutral
Ground
Live
Aquastat Wiring
Use Honeywell Aquastat
(Model L6006A or L6006C)
Notes:
1. Noritz recommends the use of an Isolation Kit with
the installation.
These kits include an integrated shut-off and serv-
ice valve with unions and a pressure relief valve.
2. Size the pump to provide a maximum of 3 GPM
with a head pressure equal to the loss through the
water heater and Air Handler.
3. Check valve required if it is not included with the
pump.
4. Set the flow switch to deactivate the Air Handler
when the domestic hot water flow reaches 3 GPM.
Adjust as necessary to prevent cycling.
5. If the system requires water for space heating at
a higher temperature than for other uses, means
such as a mixing valve shall be provided to temper
the water for the other uses to help prevent scald
-ing.
6. Expansion tank required if a backflow preventer is
installed.
Backflow Preventer
(optional)
Cold Water
Supply
Fixtures
105
R
B
S
W