Noritz NCC300DV - Page 45

45
G
(1 1/4"-2")
(3/4"-1 1/4")
Hot Water Supply
Circulation Pump 1
Circulation Pump 2 (If Necessary)
Remote Controller
Pump Control Wires
(Use an external relay)
When installing 2 pumps in parallel
*
Set “Yes” for the question“
Start pump rotation
?”
in system settings.
(See System controller unit Installation Manual)
Gas Pipe
Hot Water Return Line
*
Size the cold water supply piping to
allow for maximum flow rates of the units.
Hot Water
Supply Pipe
(1 1/4"-2")
Expansion Tank
Cold Water Supply Pipe
Unit
6
Unit
2
Unit
1
System Controller
B-1. Example of Recirculation with a Multi-System (Recirculation system)
This system will make hot water more quickly available to remote xtures.
The pump will circulate water through the loop until the entire loop is warm, and then the system
controller will turn o󰀨 the pump until the loop cools down.
* Size the pump to provide at least 2 GPM @ 10 feet of head + piping losses through the system.
Check the maintenance monitors on the unit to make sure the pump is providing adequate ow.
•
Make sure that the ow rate is not greater than 4 ft./sec.
(3/4”: 5 GPM, 1 1/4”: 13 GPM) If the ow is too low, the recirculation loop temperature will not be warm enough, if the ow is too
high, the lifetime of the unit will be reduced.
* If there are multiple circulation loops, try to make the ow rate .75-1.25 GPM in each loop. * Use copper or stainless water piping for the entire system.