Model 4
1500 - 6000 MBTU/hr
Rev. 03-08
Section B2-32
5.
[Optional] Automatic electric ignition of the premix gas pilot
shall be furnished. An electric scanner, of the UV principle,
shall confirm the pilot prior to the delivery of the low fire oil
supply.
6.
The single combustion air damper motor shall operate the low
and high fire oil valves. The damper motor shall regulate the
fire according to system demand in response to the firing rate
control.
I.
Burner Design – Gas and No. 2 Oil
1.
The burner shall be the high radiant multi–port type for gas and
shall be the pressure atomizing for oil. The burner must be
approved for operation with either natural gas or commercial
grade No. 2 oil.
2.
The burner shall operate on the low–high–low principle, and
must return to the low fire position prior to ignition.
3.
The burner shall remain in the low fire position during ignition
and until main flame has been proven.
4.
Automatic electric ignition of the premix gas pilot shall be
furnished. An electric scanner, of the UV principle, shall
monitor the pilot, preventing the primary fuel valve from
opening until the pilot flame has been established.
5.
The single combustion air damper motor shall operate the low
and high fire oil valves and the gas butterfly valve. The damper
motor shall regulate the fire according to system demand in
response to the firing rate control.
J. Main
Gas Train
1.
The gas burner piping shall include a primary gas shutoff valve.
It shall be controlled by the programming relay to start or stop
the burner and to close automatically in the event of power
failure, flame failure, or a low water condition.
2.
A manual shutoff valve shall be located ahead of the primary
gas valve.
3.
A plugged leakage test connection and a second manual shutoff
valve shall be provided as a means for a tightness check of the
primary shutoff valve.
4.
A gas pressure regulator shall be factory mounted and piped for
pressure regulation to the burner.
5.
Gas Train Components
a.
[Sizes 1500–2500] The primary gas shutoff valve shall
be motorized with a proof of closure switch.
b.
[Sizes 3000–5000] The primary gas shutoff valve shall
be motorized with a proof of closure switch. High and low
gas pressure switches shall be provided.
c.
[Size 6000] The primary gas shutoff valve shall be
motorized with a proof of closure switch. A second gas
safety shutoff valve and an additional plugged leakage test
cock shall be provided. High and low gas pressure
switches shall be provided.
