Page 6
LAARS HEATING SYSTEMS
operate at high altitudes have appropriate
stickers or tags attached.
3.
The figures in Table 3 should be used to size the
gas piping from the gas meter to the boiler.
Check local codes for BTU/h capacity required.
4.
Install a sediment trap (drip leg) ahead of the gas
controls (see Figure 4). Fit the trap with a
threaded cap which can be removed for cleaning.
5.
When required by code, install a second manual
gas shutoff valve. Do not remove manual shutoff
valve supplied with the boiler.
6.
Disconnect the boiler and its individual shutoff
valve from the gas supply piping system during
pressure testing of the system at pressures higher
than 1/2 psi (3.5 kPa). Isolate the boiler from the
gas supply piping system by closing its
individual manual gas shutoff valve during any
pressure testing of the gas supply piping system
at test pressures equal to or less than 1/2 psi
(3.5 kPa).
7.
Gas supply pressures to the boiler are listed in
Table 4.
Supply Pressure
Water Column
Natural Gas
Propane Gas
in.
mm
in.
mm
Minimum
5
127
9
229
Maximum
9
229
14
356
Table 4. Gas Supply Pressure Requirements.
au systéme d’évacuation est mis à l’air libre de
façon adéquate. Remettre les portes et les
fenêres, les ventilateurs, les registres de
cheminées et les appareils au gaz à leur position
originale.
7.
Tout mauvais fonctionnement du systéme
d’évacuation commun devrait êvacuation
commun devrait être corrigé de façon que
l’installation soit conforme au National Fuel
Gas Code, ANSI Z223.1/NFPA 54 et (ou) aux
codes d’installation CAN/CGA-B149. Si la
grosseur d’une section du systéme devrait être
modifié ppour respecter les valeurs minimales
des tableaux pertinents de l’appendice F du
National Fuel Gas Code, ANSI Z223.1/NFPA 54
et (ou) des codes d’installation CAN/CGA-B149.
2F. Gas Supply and Piping
Review the following instructions before
continuing the installation.
1.
Gas piping installation must be in accordance
with the latest edition of ANSI Z223.1/NFPA 54.
In Canada, the installation must be in accordance
with CAN1-B149.1 or .2 and all local codes that
apply. See Figure 3 for boiler gas valve
arrangement.
2.
Check the rating plate to make sure the boiler is
fitted for the type of gas being used. Laars
boilers are normally equipped to operate below a
2000 foot (610m) altitude. Boilers equipped to
Distance from Gas Meter or Last Stage Regulator
0-100 feet
100-200 feet
200-300 feet
0-30m
30-60m
60-90m
Natural
Propane
Natural
Propane
Natural
Propane
Size
in.
mm
in.
mm
in.
mm
in.
mm
in.
mm
in.
mm
320M
400M
520M
625M
775M
1000M
1.25
1.25
1.50
1.50
2.00
2.00
32
32
38
38
51
51
1.25
1.25
1.25
1.25
1.50
1.50
32
32
32
32
38
38
1.50
1.50
2.00
2.00
2.00
2.50
38
38
51
51
51
64
1.25
1.25
1.50
1.50
1.50
2.00
32
32
38
38
38
51
1.50
2.00
2.00
2.00
2.50
3.00
38
51
51
51
64
76
1.50
1.50
1.50
2.00
2.00
2.50
38
38
38
51
51
64
Notes: 1. These numbers are based on 1/2 inch (13mm) water column pressure drop.
2. Check supply pressure and local code requirements before proceeding with work.
3. Pipe fittings must be considered when determining gas pipe sizing.
Table 3. Natural Gas and Propane, Pipe Size Requirements.
