1-27
INSTALLATION
HC SERIES BOILERS
HC 13-50, HC 23-84, HC 29-106, HC 20-125, HC 33-160
GAS PIPING
The boiler should normally have an inlet gas pressure of at least 7.0" w.c. for
natural gas and 11" w.c. for propane gas. For either fuel, the inlet pressure shall
be no greater than 14.0" w.c. Confirm this pressure range is available with your
local gas supplier.
The inlet gas connection of the boiler’s gas valve is 1/2" NPT (male).
Adequate gas supply piping shall be provided with no smaller than 1/2" Iron Pipe
Size (e.g. Iron Pipe Size (IPS) and using a 1" w.c. pressure drop, in accordance
with the following chart:
MODEL
1/2" IPS
3/4" IPS
1" IPS
HC Series (Natural Gas)
20'
70'
200'
HC Series (Propane)
50'
200'
600'
Table 6: Maximum Pipe Length (ft) – HC series 33-160 boiler
Gas piping must have a sediment trap ahead of the boiler’s gas valve
(see Figure
31).
A manual shutoff valve must be located outside the boiler, in accordance
with local codes/standards. All threaded joints in gas piping should be made with
an approved piping compound resistant to the action of natural gas/propane. Use
proper hangers to support gas supply piping as per applicable codes.
The boiler must be disconnected or otherwise isolated from the gas supply
during any pressure testing of the system at test pressures in excess of 1/2 psig.
Dissipate test pressure prior to reconnecting. The boiler and its gas piping shall
be leak tested before being placed into operation.
•
The boiler and its individual shutoff valve must be disconnected from the
gas supply piping system during any pressure testing of that system at test
pressures in excess of 1/2 psi (3.5 kPa).
•
The boiler must be isolated from the gas supply piping system by closing,
disconnecting and capping its individual manual shutoff valve during any
pressure testing of the gas supply piping system at test pressures equal to or
greater than 1/2 psi (3.5 kPa).
The gas valve is provided with pressure taps to measure gas pressure upstream
(supply pressure) and downstream (manifold pressure) of the gas valve
(see
Figure 30).
Note that manifold pressure varies slightly in accordance with firing
rates with the modulating series boilers, but will always be close to 0" w.c.
1.7
Figure 31: Gas Piping
Figure 30: Gas Valve
WARNING
This boiler model can burn
either Natural gas or Propane.
Refer to section 3.3 for further
instruction.
If a boiler is to be converted from
one fuel to another, a conversion
kit must be ordered prior to the
conversion. The conversion
kit must be installed according
to the detailed instructions
supplied with the kit.
Failure to perform the required
fuel conversion correctly can
result in serious injury or death.
NOTE
It is essential to check gas
supply pressure to each
boiler with a manometer or
other high-quality precision
measuring device. Pressure
should be monitored before
firing the boiler, when the
regulator is in a “lock-up”
condition and during operation,
throughout the boiler’s full
modulation range.
Pay special attention to retrofit
situations where existing
regulators may have an over-
sized orifice and/or worn seats,
causing pressure “creep” and
high lock up pressures.
