Boiler Model - Weil-McLain WM97+70 Manual

WM97+ -
gas fired water boiler
System piping
WM97+70/110 Zone valve zoning — direct connection
Figure 47
(boiler primary/secondary by-pass valve CLOSED)
WM97+70 or 110 boiler
1
Indirect water heater, if used
2
(for CWH installations, refer
to the Weil-McLain CWH
manual)
Relief valve, supplied with
3
boiler, field piped — MUST
be piped to boiler supply
connection — see page 13 for
information
Relief valve piping to drain —
4
see page 37
DHW circulator
5
Isolation valves
6
Part number 550-142-085/0712
— Boiler Manual
(continued)
Legend — Figure 46, page 42 & Figure 47, page 43
Supplementary expansion
8
tank, diaphragm type, if used
Air separator
9
10 Flow/check valve
11 Purge/drain valves (one drain
valve is supplied loose with the
boiler)
Boiler circulator, with inte-
12
gral flow/check valve, factory
installed in boiler
13 Zone valves
Primary/secondary by-pass
14
valve — see page 38 for infor-
mation — CLOSED: Boiler
circulator provides system
flow
DHW refers to an indirect-fired domestic hot
water storage tank. CWH refers to a Weil-
McLain Companion Water Heater.
The system must meet the following
Figure 48
requirements when applying Figure 47

Boiler model

MAIN line size (inches)
[ ]
BRANCH line size
(inches) [ ]
Total FLOW, GPM
Boiler internal circulator:
TACO model
Circulator HEAD (feet)
available to the system
Finned-tube baseboard (¾") applications:
Minimum NUMBER of
circuits
Maximum FLOW per
circuit, GPM (20°F
temperature drop)
Maximum LOAD per
circuit, MBH
Maximum FEET
of FINNED TUBE
BASEBOARD per loop
(@ 600 BTUH per foot)
L
— Maximum circuit
length, feet (see L–1, L–2
and L–3 in Figure 47)
20 Make-up water supply
21 By-pass pressure regulator,
RECOMMENDED for zone
valve systems unless other
provision is made
23 Backflow preventer, if used
25 Pressure reducing valve, if
used
Internal expansion tank,
26
diaphragm-type
27 Quick-fill valve, if used
DHW boiler water supply
28
connection, when used — see
page 13 for information
WM97+70 WM97+110
1 1
¾ ¾
6.3 9.9
007-IFC 0015-IFC
5.0 6.5
2 3
3.5 4.0
35 40
58 67
102 105
DHW boiler water return
29
connection, when used — see
page 13 for information
Pressure/temperature
30
gauge, supplied with boiler,
field piped
31 Heating circuits
32 Additional heating circuits, if
any
= Items supplied with boiler
— all other items supplied by
installer
– 43 –