31
B-1. Example of Recirculation with a Multi-System
This system will make hot water more quickly available to remote fixtures.
The pump will circulate water through the loop until the entire loop is warm, and then the system
controller will turn off the pump until the loop cools down.
G
(1 1/4"-2")
(3/4"-1 1/4")
Hot Water
Supply
Circulation Pump 2
(If Necessary)
Circulation Pump 1
System select connector
Connect to the "Recirculation System"
connector.
Remote Controller
Pump Connection Wire (for pumps
> 85 W, use an external relay)
When installing 2 pumps in parallel
* Set dipswitch 3 to "OFF".
(See SC-201-6M Installation Manual)
Gas Pipe
Hot Water Return Line
*
Size the water supply piping to
allow for maximum flow rates
of the units.
Hot Water
(1 1/4"-2")
Water supply
* Also disconnect this connector on units 2-6
Disconnect this Connector
Expansion
Tank
Unit
6
Unit
2
Unit
1
System Controller
*
Size the pump to provide at least 7.6 L/min. (2 GPM) @ 30kPa (10 ft.) of head + piping losses
through the system. Check the maintenance monitors on the unit to make sure the pump is
providing adequate flow.
•
Make sure that the flow rate is not greater than 1.2m/sec. (4 ft./sec.)
(3/4”: 19 L/min. (5 GPM), 1 1/4”: 49 L/min. (13 GPM))
If the flow is too low, the recirculation loop temperature will not be warm enough, if the flow is too
high, the lifetime of the unit will be reduced.
*
If there are multiple circulation loops, try to make the flow rate 2.8 - 4.7 L/min. (.75-1.25 GPM) in each loop
.
*
Use copper or stainless water piping for the entire system.
