Crown Boiler PHNTM399, Installation And Operating Instructions Manual

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36
NOTICE
Failure to maintain the flow through boiler within
specified limits could result in erratic operation
or premature boiler failure.
1. Near boiler piping must isolate Phantom
boiler from system piping via closely spaced
tees to insure specified flow range through
boiler any time the boiler is firing.
a. The flow rate through the isolated near-boiler
loop is maintained by installer supplied
boiler circulator. See Tables 14A and 14B for
recommended circulators.
b. The flow rate through the isolated near-boiler
loop is completely independent of the flow rate
through the heating system loop(s).
c. The flow rate through the heating system loop(s)
is controlled by installer sized/provided system
loop circulator(s).
d. This piping arrangement can be used either for
space heating-only applications or space heating
with indirect water heater(s) applications.
i. Space heating only - refer to Tables 14A and
14B and Figure 20 “Near Boiler Piping -
Heating Only” as applicable.
ii. Space heating plus indirect water heater(s)
– refer to Tables 14A and 14B and Figure 21
“Near Boiler Piping - Heating Plus Indirect
Water Heater” as applicable.
iii. If piping indirect water heater off boiler
(see Figure 22A), be sure that indirect water
heater and domestic hot water circulator are
sized to maintain flow through boiler within
limits shown in Table 13.
NOTICE
Where it is not possible to install a separate
boiler loop, the system circulator must be
sized to ensure that the flow through boiler
stays within the defined parameters to prevent
overheating when the boiler is fired at it’s full
rated input. Install a flow meter to measure the
flow, or fire the boiler at full rate and ensure the
boiler D T does not exceed 35°F (19°C).
2. Direct connection of Phantom boiler to
heating system, similar to a conventional
boiler, is NOT RECOMMENDED because:
a. The flow rate through system must be the same
as through boiler and fall within limits specified
in Table 13.
VI. Water Piping and Trim
A. Factory Supplied Piping & Trim, B. Piping System to be Employed
(continued)
7. Mount (1) 1½ in. NPT 2 in. long nipple into
1½ in. FPT boiler supply tapping (see Figures
1A and 1B). Then, install 1½ in. x 1½ in. x ¾
in. NPT tee onto the nipple, making sure ¾ in.
branch outlet is in horizontal plane and facing
the boiler front.
8. Install ¾ in. x ¼ in. NPT black reducing
bushing into the tee branch. Then, put in
temperature & pressure gauge.
9. Install second 1½ in. NPT x 2 in. long nipple
into 1½ in. x 1½ in. x ¾ in. NPT tee run.
10. Mount 1½ in. x 1½ in. x 1 in. NPT black tee
onto the nipple, making sure tee 1 in. NPT
branch outlet is in upright position.
11. Remove flow switch and paddles from
packaging carton. Also see/follow Taco
Instruction Sheet for Flow Switch Kit (supplied
with the flow switch) for specific details.
12. Select the paddle stamped “1” for the
PHNTM399 and PHNTM500.
13. Attach paddle to flow switch stem using
supplied machine screw.
14. Apply pipe dope to the switch-threaded brass-
bushing end. Then, mount the switch threaded
end with the attached paddle into 1-1/2 in. x
1-1/2 in. x 1 in. NPT tee branch and tighten
such that distance between bottom of switch
housing and top of tee branch is approximately
1-11/16 in. (43 mm). Insure the switch paddle
is positioned perpendicular to the flow direction
for the best flow sensitivity. Do not tighten the
switch by grasping the switch enclosure. Use
the wrenching flats on the bushing only. The
turning radius required for the switch mounting
is 3 in. (80 mm).
15. For flow switch wiring refer to Section VIII
“Electrical” of these instructions.
B. Piping System To Be Employed.
Phantom boilers are designed to operate in a closed
loop pressurized system. Minimum pressure in the
boiler must be 20 psi (140 kPa). Proper operation of the
Phantom boiler requires that the water flow through the
boiler remain within the limits shown in Table 13 any
time the boiler is firing.