Weil-McLain WM97+ Product Manual page 9

CWH
companion water heater
Domestic water piping
Domestic water supplied to fixtures that could pose
an injury hazard due to high temperature, such as
showers and faucets, should be equipped with a
temperature regulating device, such as an
mixing valve
.
When the supply pressure is higher than 70 PSIG,
pressure reducing valve
install a
supply line to prevent water loss through T&P relief
valve. A thermal expansion tank is also required.
This symbol, where used in this manual, indicates the
item is required by Massachusetts code.
This symbol indicates the item is optional, unless
required by applicable codes.
1
Companion Water Heater (CWH) — stainless steel heat
exchanger and tank with integral foam enclosure — shown with
WM97+155 boiler and right-side piping connections — piping can
be routed either side or both, depending on clearances (see page 7
for instructions to mount and connect the mixing valve supplied
with the CWH)
2
WM97+ boiler — Model WM97+70, 110 or 155 (155 shown)
3
Domestic water cold inlet
4
DHW mixed outlet from mixing valve
5
Mixing valve cold water tee (supplied with mixing valve)
5a
Mixing valve flexible metal connector (supplied with
mixing valve)
6
Honeywell mixing valve — Figure 6, page 8 shows
the Honeywell AMX302TLF mixing valve assembly — refer to
mixing valve literature supplied with the CWH — AMX302TLF is
ASSE 1017 compliant.
6b
6a
6a
Mixed temperature adjustment knob —
DO NOT adjust this knob without following instructions supplied
with mixing valve assembly.
6b
Mixing valve hot water inlet port (HOT) — ¾" FNPT
— Connects directly to CWH hot water outlet pipe
6c
Mixing valve mixed water outlet port (MIX) — ¾"
MNPT — domestic hot water system supply connection
6d
Mixing valve recirculation port (R) — ½" FNPT —
Recirculation connection — Follow mixing valve instructions and
information beginning on page 10
3/8" Allen wrench to remove.)
6e
Mixing valve cold water inlet port (COLD) — ½" flare
fitting — Assemble mixing valve components (items 5, 5a and 6)
according to the instructions supplied with the mixing valve.
6f
(AH) — DO NOT USE — The water from this
Part number 635-500-156/0113
— Product Manual
(continued)
LEGEND for Figure 6, page 8
anti-scald
on cold water
6f
6d
6c
6e
of this manual. (Requires
port is not regulated by the mixing valve.
7
T&P relief valve (mounted in top of CWH) — supplied
with CWH
• Use only the T&P valve supplied with the water heater.
See Replacement parts for part number.
• Install the T&P relief valve as shown in the piping con-
nection instructions in this manual.
8
T&P relief valve discharge piping —
• Must be made of material serviceable for temperatures
of 250°F or greater.
• Must be directed so that hot water flows away from all
persons.
• Must be directed to a suitable place for disposal.
• Must be installed so as to allow complete draining of the
T&P relief valve and discharge line.
• Must not be excessively long.
• Must not be directly connected to a drain — terminate
discharge piping within 6" from floor — refer to local
codes.
• Must not be plugged, reduced or restricted or terminated
with a threaded end.
• Must not be subjected to freezing.
Do not install any valve between the T&P relief
valve and CWH connection, or on T&P relief valve
discharge piping. Do not plug T&P relief valve or its
discharge piping. Improper placement and piping
of T&P relief valve can cause severe personal injury,
death or substantial property damage.
• Pipe from relief valve to floor drain, if available.
9
Domestic mixed water supply to system
10
Thermal expansion tank —
REQUIRED
• if cold water line is equipped with a backflow
preventer or pressure reducing valve — see
TANk WARNING
on page 8.
11
DHW drain valve — supplied with CWH
• Install the drain valve on the cold water inlet tee (port
AC) as shown.
12
Isolation valves
13
Cold domestic water supply
14
Backflow preventer —
for Commonwealth of Massachusetts)
15
Pressure reducing valve —
REQUIRED
• when the supply pressure is higher than
70 PSIG — A thermal expan
16
Unions
17
Vacuum breaker —
18
Shock arrester —
Dishwashers, clothes washers, and fast-closing positive
shutoff valves incorporated in the system all contrib-
ute to creating water shock. Install a water hammer
arrester to prevent damage to pipes and appliances.
See control manufacturer's instructions for applica-
tion and installation.
19
Heat trap loops (12" minimum) —
ExPANSION
— —
(required
.
sion tank is also required
9