1g. combustion air supply – LAARS Mini-Therm JVi - Install and Operating Manual User Manual
Page 6
Mini-Therm JVi
Page 5
are normally equipped to operate below a 2000'
(610m) altitude. Boilers equipped to operate at
higher altitudes have appropriate stickers or tags
attached next to the rating plate.
2.
Use the figures in Table 5 to provide adequate
gas piping from the gas meter to the boiler.
3.
A trap (drip leg) must be provided ahead of the
gas controls (see Figure 3). A manual gas shutoff
valve approximately 5' (1.5m) above the floor
must also be provided for service, convenience
and safety. Check the local codes.
4.
Disconnect the boiler from the gas supply pipe
before pressure testing the pipe for gas leaks.
5.
Provide gas supply pressure to the boiler per
Table 6. The regulator is pre-set at the factory,
and normally requires no further adjustment.
NOTE : The boiler and all other gas appliances
sharing the boiler gas supply line must be firing at
maximum capacity to properly measure the inlet
supply pressure. Low gas pressure could be an
indication of an undersized gas meter and/or
obstructed gas supply line.
6.
Before operating the boiler, the complete gas
supply system and all connections must be tested
for leaks using a soap solution.
1G. Combustion Air Supply
The boiler location must provide sufficient air
supply for proper combustion, and ventilation of the
surrounding area as outlined in the latest edition of
C
B
2.4
(6.1)
A
DRAIN
11.8
(298)
6
(152)
7
(178)
24 (610)
REF.
INDUCED
DRAFT
BLOWER/
MOTOR
PULL-OUT
GAS
MANIFOLD
BURNER
TRAY
TEMP./PRESSURE
GAUGE
TEMPERATURE GAUGE
1-1/4" NPT TEE
2X
Figure 2. Dimension Information.
4
(102)
DIA.
25
(635)
REF
8.9
(226)
18 (457) REF.
4.9
(124)
Table 5. Gas Piping Sizes.
Table 6. Gas Pressure Measurement.
Table 7. JVi Dimensions.
Distance
From
Gas
Meter in
Feet (m)
Boiler Size
50
75
100
125
160
225
Inches
0-50'
(0-15)
1/2
3/4
3/4
3/4
1
1
50-100'
(15-30)
3/4
3/4
3/4
1
1
1-1/4
100-200'
(30-60)
3/4
1
1
1
1-1/4
1-1/4
NOTE: These figures are for Natural Gas (.65 Sp. Gr.), and are based
on 1/2" water column pressure drop. Check supply pressure with a
manometer, and local code requirements for variations. For LPG,
reduce pipe diameter one size, but maintain a 1/2" minimum diameter.
A 'normal' number of Tees and elbows have been taken into allowance.
Size
A
B
C
Water
Connection
Gas
Connection
in.
mm
in.
mm
in.
mm
50
75
100
125
160
225
13-3/8
13-3/8
16-7/8
16-7/8
20-3/8
25-5/8
340
340
429
429
518
651
3-1/8
2-1/4
5-3/4
5-1/2
7-1/4
10
79
57
146
140
184
254
2-7/8
2
2-7/8
2
2
2
73
51
73
51
51
51
1-1/4
1-1/4
1-1/4
1-1/4
1-1/4
1-1/4
1/2
1/2
1/2
1/2
1/2
3/4
Dimensions in
inches (mm).
Natural Gas
Propane (LP)
Gas Pressure
in. W.C.
kPa
in. W.C.
kPa
Minimum Supply
Pressure
5.5
1.4
10
2.5
Maximum Supply
Pressure
9
2.2
14
3.4
Manifold Gas
Pressure
4
1
9
2.2