23
MECHANICAL VENTING
SINGLE UNIT INSTALLATION
When mechanical venting of these heaters is desired, the
following kits are available.
BTR(C) 120 through the BTR(C) 200/A
A. O. Smith part number 193933
BTR(C) 250/A through the BTR(C) 500/A
A. O. Smith part number 193933-1
Where an approved power venter is to be installed to operate in
conjunction with the water heater thermostat, the following codes
must be adhered to. Field wiring should conform to the latest
version of the National Electric Code ANSI/NFPA No. 70. For
Canadian installations the electrical connections and grounding
shall be done in accordance with the current Canadian Electrical
Code CSA C22.1 Part 1 and/or local codes.
NOTE: The power venter must be installed downstream of the
drafthood. See figure 14.
FIGURE 14
VENT INSTALLATION
Seal all joints between the power venter and the vent termination.
This is to prevent leakage of exhaust products into the room(s)
due to positive pressure of blower.
The "Sequence of Operation" description will be the same with
mechanical venting except,
When the appliance thermostat calls for heat:
Thermostat contacts "Close" and the power venter blower
(120 VAC) is energized. Sufficient draft must be established for
the "Draft Prover Switch (N.O.)" to "Close". When the draft prover
switch "Closes" the relay coil of the flue damper is energized.
See side wall vent kit installation manual for complete
instructions.
MULTIPLE UNIT INSTALLATIONS
For multiple unit installations, contact A.O. Smith Water Products
Company, Technical Support Center at 1-800-527-1953. In
Canada, contact A.O. Smith Enterprises, Ltd. at 1-800-265-8520.
T
ABLE 5
MANIFOLD GAS PRESSURE IN INCHES
OF WATER COLUMN (ALL MODELS*)
TYPE OF GAS
NATURAL
PROPANE
3.5
10.0
Gas pressure specified in Table 5, refer to flow pressure taken
at pressure tap of automatic gas valve while heater is operating.
TABLE 6
APPROXIMATE TIME REQUIRED TO CONSUME
1 CU. FT. OF GAS AT FULL CAPACITY
INPUT
TYPE
BTUH
TIME REQ’D
RATE
OF
PER
TO CONSUME
(BTUH)
GAS
CU. FT.
1 CU. FT.
OF GAS
120,000
NATURAL
1050
31.5 SEC.
PROPANE
2500
75.0 SEC.
154,000
NATURAL
1050
24.5 SEC.
PROPANE
2500
58.4 SEC.
180,000
NATURAL
1050
21.1 SEC.
PROPANE
2500
50.3 SEC.
190,000
NATURAL
1050
19.9 SEC.
PROPANE
2500
47.4 SEC.
199,000
NATURAL
1050
19.0 SEC.
PROPANE
2500
47.4 SEC.
250,000
NATURAL
1050
15.1 SEC.
PROPANE
2500
35.3 SEC.
251,000
NATURAL
1050
15.06 SEC.
PROPANE
2500
35.1 SEC.
275,000
NATURAL
1050
13.75 SEC.
PROPANE
2500
32.2 SEC.
305,000
NATURAL
1050
12.4 SEC.
PROPANE
2500
29.5 SEC.
360,000
NATURAL
1050
11.4 SEC.
PROPANE
2500
24.0 SEC.
365,000
NATURAL
1050
10.4 SEC.
PROPANE
2500
24.7 SEC.
399,000
NATURAL
1050
9.5 SEC.
PROPANE
2500
22.6 SEC.
500,000
NATURAL
1050
7.6 SEC.
PROPANE
2500
18.0 SEC.
Figures shown are valid for 0-2000 ft.(0-610m) installations.
See “HIGH ALTITUDE INSTALLATIONS” for deration
requirements over 2000 ft.(610m)
TABLE 7
PILOT BURNER INFORMATION
TYPE OF
PILOT BURNER
RATED
MODEL
GAS
PART NUMBER
ORIFICE
(WITH ORIFICE)
SIZE
ALL
NATURAL
193314-0
0.018
MODELS
PROPANE
193314-1
0.014
