28
G
(1 1/4"-2")
(3/4"-1 1/4")
Hot W
ater
Supply
Circulation Pump 1
Circulation Pump 2
(If Necessary)
Remote Controller
Pump Control Wires
(for pumps > 85 W
, use an external relay)
When installing 2 pumps in parallel
*
Set “Yes” for the question
“
Start pump rotation
?”
in system settings.
(See SC-301-6M Installation Manual)
Gas Pipe
Hot W
ater Return Line
*
Size the cold water supply piping to
allow for maximum flow rates
of the units.
Hot W
ater
Supply Pipe
(1 1/4"-2")
Expansion
T
ank
Cold W
ater 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 fi xtures.
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.
*
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
fl o
w.
•
Make sure that the
fl
ow rate is not greater than 4 ft./sec.
(3/4”: 5 GPM, 1 1/4”: 13 GPM)
If the
fl
ow is too low
, the recirculation loop temperature will not be warm enough, if the
fl
ow is too
high, the lifetime of the unit will be reduced.
*
If there are multiple circulation loops, try to make the
fl
ow rate .75-1.25 GPM in each loop.
*
Use copper or stainless water piping for the entire system.
