6
Hydronic piping
Near boiler piping connections
Figure 6-3A Near Boiler Piping w/Y-Strainer
Figure 6-3B Near Boiler Piping w/Low Loss Header
40
Installation & Operation Manual
Variable speed pump option
Variable speed pump setup
Before operation, ensure the following:
-
Pump is set for an input signal of 0 - 10VDC
by the dip switches on the pump control
-
Pump is set for external signal control
(if applicable)
-
Pump is set for linear output (if applicable)
-
If pump does not come equipped with a
0 - 10 VDC input option, an optional module
will be required from the vendor
SMART SYSTEM / Multi-temperature
loop control option
Th e FTXL boiler is capable of producing up to three
(3) set point temperatures to meet diff erent space
heating demands.
temperature demand it is necessary to protect the
lower temperature loop(s) from overheating. To help
aid with this protection, Lochinvar off ers the Multi-
Temperature Loop Control Board Kit (100167843).
Th e maximum allowable water fl ow rate
CAUTION
through a single FTXL boiler is 105 GPM
(Models 400 - 600) and 150 GPM (Models
725 - 850). Exceeding this fl ow rate will
result in damage to the heat exchanger and/
or piping.
Reference Table 6A1 for the minimum
NOTICE
recommended fl ow rate through a single
FTXL boiler at full fi re to maintain a 80°F
temperature rise. Reference Table 6A2 for
the absolute minimum fl ow rate through a
single FTXL boiler.
Table 6A1 Minimum Flow Rate with the Boiler at Full Fire
TEMPERATURE RISE APPLICATIONS
MODEL
FTX(N,L)400
FTX(N,L)500
FTX(N,L)600
FTX(N,L)725
FTX(N,L)850
[Based on 80°F Temperature Rise]
Table 6A2 Absolute Minimum Flow Rate @ Low Fire
ABSOLUTE MINIMUM FLOW RATE
MODEL
FTX(N,L)400
FTX(N,L)500
FTX(N,L)600
FTX(N,L)725
FTX(N,L)850
When using more than one
FLOW RATE (GPM)
10
12
15
18
21
FLOW RATE (GPM)
4
4
4
4
4