Instruction manual

Part number 550-100-116/0714
26
SlimFit
™
COMMERCIAL CONDENSING GAS-FIRED WATER BOILER — Boiler Manual
&IGURE Piping layout — typical piping for multiple SlimFit boilers, with DHW storage heater (or heaters) direct-piped to
one of the boilers
SF3158a
1
2
3
4
5
6
7
8
9
13
17
18
19
25
30
2
2
2
2
36
4
5
1
2
3
17
25
2
1
2
3
17
25
2
37
2
21
27
Drain
valve
2
30
Multiple boiler water piping (continued)
Legend — Figure 24
1 Check valve (each boiler)
2 Isolation valves
3 Strainer (recommended on return line to each
boiler)
4 Multiple boiler manifold (supply)  layout and
size per Figure12, page15
5 Multiple boiler manifold (return)  layout and size
per Figure12, page15
6 Primary pump
7 Expansion tank (diaphragm type shown)
8 System air eliminator
9 System automatic air vent
13 Cold water supply (requires items 10, 11 and 12 as
shown in Figure21, page23)
17 Boiler pump (each boiler)
18 System supply
19 System return
20 Boiler relief valve and discharge piping (not shown)
 install per page14 and all applicable codes
21 Indirect-red storage water heaters (Weil-McLain
AQUA shown). See water heater manual for DHW
piping.
25 External drain/blowdown valve, when used, ¾”
NPT or larger
27 Flow/check valve in DHW piping
30 Strap system supply sensor to the system pipe
as shown. Place sensor at least 6 pipe diameters,
but no more than 10 pipe diameters, from boiler
supply connection to the system pipe.
36 Secondary connection to boiler manifolds  space
no greater than 8 pipe diameters apart
37 DHW pump
Set the Sola control so the boiler pumps, item 17, operate
on any call for heat, whether heating system or DHW.
Oset the DHW boiler-side supply and return manifolds
as shown so the total run of pipe and ings to each of
the water heaters is approximately equal.
DHW tanks piped using this arrangement need to be sized for
the required load, with a DHW pump selected to provide a ow
rate through the boiler and tank that is within the allowable ow
rate range listed in Figure13, page15 of this manual.
r Use 3” or larger piping for all
connections between boilers and
manifolds.
r Follow all sizing guidelines on
page15. Pumps must provide
ow rates required.
r Use recognized engineering
design practices throughout.