1-17
INSTALLATION
SL 30-175, SL 45-260 MODULATING GAS BOILERS
Do not place any water connections overhead the boiler;
leaks can damage
the fan & controls. if needed, create a shield over the top of the cover, but allow
clearance for airflow and service access.
For best results, use a
Primary: Secondary
piping system, with a pumped
boiler loop using 1 1/2" piping for the either the sl 30-175 or sl 45-260. Heat
exchanger head is only 2’ at 6 gpm and approx. 13' at 25 gpm.
The minimum flow rate required through the heat exchanger is 6 gpm and a
maximum of 25 gpm is allowed. Primary/secondary piping ensures adequate
flow and de-couples Δ°T issues (boiler vs. distribution). Aim for a 20° to 30° F Δ°T
across the heat exchanger at high fire (there is a boiler protection throttle fence
limiting the Δ°T to 35°F).
the sl series modulating boilers are designed to supply three different
heating loads with temperatures within the range 34°F to 180°F - to meet three
separately piped loads. use closely spaced tees to connect each pumped “load”
(e.g. DHW, baseboards or radiant floor) to the primary loop, or employ the use
of a hydraulic separator to isolate the boiler loop from the system and pipe the
system from the secondary side of the separator. two-load systems may be
piped with a variant of parallel piping commonly used.
always ensure that loads sensitive to high temperatures are protected using
means such as a mixing valve set for maximum limit (say 140°F) to protect
radiant floors, or an aquastat (wired to the boiler’s auxiliary interlocks).
A variety of application drawings showing basic design options are available from
the IBC web site at: www.ibcboiler.com
bOILER HEAD LOSS SL 30-175, SL 45-260
Flow rate (gpm)
6
10
15
20
25
Head @ flow (ft wc)
2’
3.5’
5.5’
8’
13’
Table 6: Pressure Vessel Head
WARNING
Close fill valve after any
addition of water to the
system, to reduce risk of
water escapement.
NOTE
Full sized and more detailed
application drawings can be
downloaded from our web
site.
www.ibcboiler.com
Table 5: Reserved
Figure 21: Primary/Secondary piping concept with hydraulic separator
FLOW
DIRECTION
PRIMARY/BOILER
CIRCULATOR
HYDRAULIC
SEPARATOR
SUPPLY TO
LOAD ONE
SUPPLY TO
LOAD TWO
SUPPLY TO
LOAD THREE
RETURN FROM
LOAD ONE
RETURN FROM
LOAD THREE
RETURN FROM
LOAD TWO
IBC
SL 30-175
SL 45-260
BOILER
IBC
IMPORTANT NOTE: NONE OF THE EXTERNAL DEVICES SHOWN
ON THIS DRAWING ARE SUPPLIED BY IBC AS STANDARD
EQUIPMENT
EXCEPT FOR THE PRESSURE RELIEF VALVE. THE
OTHER DEVICES CAN BE PROVIDED BY YOUR IBC DISTRIBUTOR
OR BY SPECIAL ORDER FROM IBC
SINGLE BOILER MULTI LOAD PIPING WITH HYDRAULIC SEPARATOR
(REFER TO FIGURE 20 THIS MANUAL, FOR CLOSELY SPACED TEE PIPING GENERAL ARRANGEMENTS)
Supply stack upper tapping - 3/4”
FIP to accept relief valve and air
vent assembly
Relief valve and air vent assembly
(recommended configuration)
Relief valve and air vent assembly
(relief valve discharge piping -
required by code -piped to back)
Summary of Contents for SL 30-175
Page 76: ...NOTES...
