Installation Ins!
GAS-FIRED FORCED AIR FURNACE
394
Series G
Size 50 thru 220
INTRODUCTION
Before installing the furnace, refer to Bryant Form
No. 39003D1 “Procedure for Gas Appliances”
(packaged with the equipment) for information con
cerning combustion, venting, piping, and other standard
installation practices. Further reference is made to the
current edition of the American National Standard
“Installation of Gas Appliances and Gas Piping,”
Z21.30.
Model 394 Gas Furnaces are shipped from the factory
completely assembled and wired ready for indoor heat
ing installation. They are manufactured with two types
of blowers: belt and direct drive. The three smaller
sizes (Series G), 50, 80, and 100. are direct drive only.
All sizes incorporate a low-voltage terminal strip for
convenience of field wiring (except HL and HH
Models).
The optional equipment available includes: Counter
flow Box; Side and Rear Drop Ducts; Side Filter
Racks; Cooling Coil Housing; Combustible Floor
Base Packages, for Counterflow Applications; Cooling
Relay Kit, for field conversion.
CAUTION:
1 ( iiimli-!iImv liii[M,.e mus' bv ui'Killvd kii .m :ip
proved non-combustible base.
2 liL siiic icmpci.iMtii. Use ll■>l■^ no! c\».cci{ ili.i
spcs-ilhil on ihc mil! i.iimu pkiic
' lie suic to chci.l' all ci'iiiiols iiii piiipci opt-i.i'ioi
upon cvimplction of installalivm.
4. Duralast filler on 125 and 137 iipflow fu.maces mus
be used with a skle filter rack or rear drop duct.
Cancels 39394D66
the manual valve knob (OFF-PILOT-ON). There is a
position stop at the PILOT position. To move the
manual valve knob from the PILOT position to either
ON or OFF position, the manual valve knob must be
depressed.
If not already checked when lighting the main burner,
check the proper operation of this valve by moving
the room thermostat pointer above and below room
temperature and observing that the main burners light
on call for heat and go off when the pointer is moved
below the room temperature setting. All Bryant auto
matic gas control valves have a delay when opening
or closing.
Automatic Pilot
To check the pilot operation, follow the instructions
below:
Attach a low-voltage test light to electrical leads of gas
valve. With thermostat set above room temperature,
shut off gas supply to burners and pilot, with main
manual shutoff valve. If test light goes out within 45
seconds, pilot is functioning properly. If light does not
go out within 60 seconds, replace pilot.
39394D73
3/30/72
I. CLEARANCE REQUIREMENTS
The upflow furnace design is certified for use on com
bustible floors.
The Model 394 design is certified by the American Gas
Association, Inc., for installation in a closet or alcove
provided the following clearances are maintained.
Sides............................................................0" (1")*
Back
............................................................
Top of Plenum.............................................3" (0")*
Vent Connector
Front............................................................6" (6")*
* Figures shown in parentheses are approved clearances
when the furnace is installed as a counterflow furnace.
Bryant Automatic Gas Control Valve
Note: On units equipped with an A-643 Bryant auto
matic gas control valve, there are three positions for
...........................................
II. CONTROLS
0" (1")*
6" (6")*
Pilots with Thermocoupie Elements
The D2 100% shutoff propane and D5 100% shutoff
natural gas controls have pilots equipped with thermo
couple elements.
The pilot flame should surround the tip of the thermo
couple. It should also extend downward to include
3/8 to 1/2 inch of the thermocouple tip. The flame
must not come in contact with any other part of the
thermocouple.
D2 Propane
The thermocouple transforms heat energy from the
pilot flame into electrical energy. The current thus
generated is sufficient to operate the 100% inline shut
off valve. The Bryant automatic gas control valve is
powered externally from the transformer, and operates
independently of the inline shut-off valve. When there
UPFLOW
FURNACE
A70652
A.G.A. RATINGS BTU/HR
Natural Propane
Model
No.
50-394
80-394
100-394
125-394
137-394
165-394
190-394 190,000 152,000
220-394 220,000 176,000
Model No.
50-394 16-1/4
80-394
100-394 18-1/4
125-394 20-1/4
137-394 20-1/4
165-394 28-1/4
190-394
220-394
*Optional gas inlet right and left sides provided. T = 33-5/8 and S = 3-1/2 on 50 thru 137 sizes only.
Input
50,000 40,000 50,000 40,000
80,000 64,000 75,000 60,000
100,000 80,000 100,000 80,000
125,000
137,500
165,000
A
26 46 14-5/8
16-1/4
26
26
26
26 46
36-1/4
36-1/4
28-13/16
28-13/16
28-13/16
Bonnet
Capacity
100,000 125,000 100,000
110,000
132,000 150,000 120,000
C D E
B
46 14-5/8
46 16-5/8 19-3/4
46 18-5/8 19-3/4
51
51
51
Input
Not Available
175,000
200,000 160,000
19-3/41
¡9-3/4
18-5/8 19-3/4
26-5/8
17-3/4 2-1/2 5 6" 25-1/4
34-5/8
17-3/4
34-5/8
17-3/4 2-1/2 5 (2) 5"
Bonnet
Capacity
140,000
F G
2-9/16
1/2
2-9/16
1/2
2-3/4 5"
1/2
2-3/4
1/2
2-3/4
1/2
2-1/2 5 (2) 5" 33-1/4
Gas Connection
Sizes
Natural Propane
1/2
1/2
1/2
1/2
1/2
1/2
1/2
1/2
H
4"
12-1/4
4"
12-1/4
14-1/4
18-1/4
5".
5" 18-1/4 22-5/8
33-1/4
BOTTOM OPTIONAL
RETURN SIDE FILTER RACK
OPENING EITHER SIDE
1/2
1/2
1/2
1/2
1/2
(2) 14 X 25 X 1 .
1/2
(1) 16 X 25 X 1
(1) 20 X 25 X 1
1/2
(1) 16 X 25 X 1
1/2
(1) 20 X 25 X 1
K
J
22-5/8
22-5/8
22-5/8
22-5/8 1-1/2
23-5/16
23-5/16
23-5/16
Bottom
Filter
Sizes
14 X 25 X 1
14 X 25 X 1
16 X 25 X 1
20 X 25 X 1
20 X 25 X 1
L
M
1-1/2
1-1/2
1-1/2
1-1/2
2-5/8 23
23
2-5/8
23
2-5/8
Side
Filter
Sizes
14 X 25 X 1
14 X 25 X 1
16 X 25 X 1
20 X 25 X 1
20 X 25 X 1
(2) 16 X 25 X 1
(2) 16 X 25 X 1
(2) 16 X 25 X 1
N P R S*
1-1/4
12
12
14
18
18
23
23
23
23
23
24 2-1/8
24
24
2-1/8
1-1/4
2-1/8
1-1/4
2-1/8
1-1/4
2-1/8
1-1/4 2-1/8
8-5/8
2-1/8 8-5/8
2-1/8 8-5/8
A66384
Approx.
Shipping
Weight
135
153
178
200
202
282
365
365
T*
2-7/8
25-7/16
2-7/8
25-7/16
2-7/8
25-7/16
2-7/8
25-7/16
2-7/8 25-7/16
30-5/8
4-1/16
4-1/16 30-5/8
4-1/16
30-5/8
is a pilot flame, the current generated by the thermo
couple holds the 100% inline shut-off valve in the open
position and the gas control valve controls the flow
of gas. Should the pilot go out, no current will be
generated by the thermocouple and the 100% inline
shut-off valve will close. No gas can then flow to the
pilot.
D5 Natural
Should the pilot go out, no current will be generated
by the thermocouple and the pilot-relay will close,
shutting off the gas to the pilot, and breaking the elec
trical circuit to the Bryant automatic gas control valve.
821/822 Adjustable Fan Control
The Model 394 Furnace incorporates the 821/822
relay for fan control. (The 821 relay is used with the
643 gas valve on furnace sizes 50 through 165 natural
gas; the 822 relay is used with the 641 valve on sizes
190 and 220 and all propane units.) The 821/822 has a
field-adjustable differential. The “max. off” setting on
the dial is for the longest “off” time and shortest
“on” time.
When facing the front of the furnace, the “off” cycle
is lengthened by moving the adjustment lever to the
Figure 1 - Control Section (D5 pilot relay shown)
left. The “off’ cycle is shortened by moving the lever
to the right. The adjustment of the “off’ cycle has the
opposite effect on the “on” cycle; however, to a lesser
degree.
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