3
High-End Gas Valve
shuts off and the
Low-End Gas
Valve is energized. At the same time the fan inlet damper is closed. As
demand continues to decrease the low end gas valve shuts off and the boiler proceeds to post purge.
c) AV3000 - AV4000 (Proven Pilot)
: The
Advantus
controller will activate the
Hot Surface Igniter
for 22 seconds followed by
energizing the
Pilot Valve
for 10 seconds, whereupon a signal of 0.8 Vdc must be recognized by the controller at the
UV
Scanner
to keep the
Pilot Valve
in an open position. The fan is kept at ignition speed until the stabilization timer is satisfied.
After the stabilization timer expires the
Low-End Gas Valve
is opened and the
Pilot Valve
is deactivated. As demand increases,
the modulation signal causes the
Low-End Valve
to draw more gas and the sequence as detailed in (b) above is followed.
10. If the flame signal is not reached, the module will stop the ignition sequence after the
“
Main Gas On
” period & recycle.
11. The fan speed will slowly decrease as the temperature nears the target. The modulation rate is controlled via a 4-20 mA signal.
If the heat demand is sustained without change, the boiler firing rate will reach a point of steady-state and the fan will rotate at
constant speed.
12. When the heat demand is satisfied or the remote enable is removed, the burner will shut off and the fan speed will ramp up to
the preset
Post-Purge
speed until the
Post-Purge
timer is satisfied.
13. The pump continues to circulate until the
Post-Purge
time is satisfied.
14. The boiler will then go into Standby as it waits for the next heat demand or remote enable.
NOTE
The
Hot Surface Igniter
is energized with 115V AC when control is switching to/from the
High-End Gas Valve
to the
Low-End Gas
Valve
. To avoid shock do not contact bare
Ignitor
wires at this time
Figure 3: Advantus Ignition Cycle
NOTE
:
1. If a flame signal is detected at the end of the
Pre-Purge
period, an error will occur.
2. If at the end of the safety period (4 sec) no flame is detected, the control will go to
Post-Purge
to remove the unburned gas.
After this, a re-ignition attempt is started following the same cycle. The number of re-ignition attempts is
Limited
to 2 after which
a lockout occurs.
3. The burner can only be on continuously for a period of 24 hours. After this, the burner is switched off and a restart sequence
follows.
4. The
Hot Surface Igniter
is de-energized at the end of the ignition period to allow for ionization detection.
1.4.1
HEAT TRANSFER PROCESS
1. Burner input rate continues to increase until water temperature reaches the set point temperature.
2. Burner input rate may stabilize at a fixed rate when demand equals input.
3. Burner input rate will decrease when water temperate approaches temperature set point.
1.4.2
END OF SEQUENCE
1. Set point temperature is reached.
2. Power to the gas valve is turned off.
3. Combustion air fan ramps to a stop over the factory pre-programmed time period.
4.
Thermostat is now in a standby mode waiting for the next “Call for Heat”.
Содержание ADVANTUS AVH 500
Страница 2: ......
Страница 3: ......
Страница 38: ...31 Figure 23 Recommended Piping with Reverse Return and Variable Primary Flow...
Страница 70: ...63 Figure 44 Typical Gas Train Models AV1000 3000 Figure 45 Typical Gas Train Models AV3500 4000...
Страница 88: ...81 PART 12 EXPLODED VIEW Figure A...
Страница 89: ...82 Figure B FAN BURNER ASSEMBLY AV500 600 some items may not be as shown...
Страница 90: ...83 Figure C FAN BURNER ASSEMBLY AV800 4000 some items may not be as shown...
Страница 91: ...84 Figure D Figure E...
Страница 92: ...85 Figure F Figure G...
Страница 93: ...86 Figure H CONTROL BOARD ASSEMBLY...
Страница 100: ...93 PART 13 ELECTRICAL DIAGRAMS...
Страница 101: ...94...
Страница 102: ...95...
