Sequence Of Operation - Lochinvar COPPER-FIN II 402 - 2072 Installation And Operation Manual

7
Operating information

Sequence of operation

OPERATION
1. The manual reset high limit must be closed before any action will
take place.
2. Upon a call for heat the control turns on the appropriate pumps
(system and boiler pumps for space heating; DHW pump for DHW
call). The flow switch and low water cutoff (if equipped) must
close.
3. • If the unit is equipped with a proof of closure valve, the
proof of closure switch must be closed.
closure valve is then energized.
switch(es) (if equipped) must close.
• If the contact for the louvers is closed, the louver proving,
and auto reset high limit (water heater only) inputs must close.
• If the air pressure switch is open, the prepurge cycle then
begins by starting the combustion blower.
the air pressure switch must close.
4. After the 15 second prepurge, the blower slows down and the hot
surface igniter (HSI) is energized. The HSI is heated for at least
20 seconds.
5. Once the HSI is hot, the trial for ignition begins with the
opening of the gas valve.
6. If the SMART SYSTEM control does not sense flame, then it will
lock out.
7. If the SMART SYSTEM control senses flame, it will fire the burner
to maintain the set point. The firing rate will stage as required to
hold the actual temperature at the set point. If the boiler lights due
to a space heating call for heat, and the ramp delay function is
active (default is disabled), the staging will be held to a series of
increasing limits after the burner has lit.
8. If the space heating call for heat is active, and a DHW call for
heat becomes active, the control will turn on the DHW pump, wait
2 seconds, and then turn off the boiler pump. This will divert the
hot water away from the heating zone(s) and send it to the DHW
tank instead. The control will then modulate to maintain the outlet
temperature to the DHW boiler set point.
9. If the DHW call for heat remains active for more than 30 minutes,
and the space heating call for heat is also on, then the control will
turn on the boiler pump, turn off the DHW pump after 2 seconds,
and resume firing based on the space heating set point. As long
as both the space heating and DHW calls for heat remain active,
the control will switch back and forth between the two modes until
one of them is satisfied.
10. Once both calls for heat are satisfied, the control will turn
off the burner. The blower will remain on for the 30 second
postpurge cycle. Any pumps that are running will continue to run
for their respective pump delay times, then turn off.
11. Boiler pump off, system pump continues its delay if longer.
12. System pump off.
(continued)
HTR:
OUT: 123.8F(129)
HTR:
OUT: 123.8F(129)
The proof of
The gas pressure
HTR:
OUT: 123.8F(129)
Once started,
HTR: PREPURGE
OUT: 123.9F(129)
HTR: IGNITION
OUT: 123.9F(129)
HTR: POSTPURGE, LOCKOUT
OUT: 123.9F(129)
HTR: RUN STG: 1
OUT: 124.8F(129)
HTR: DHW STG 123
OUT: 177.8(180)
HTR: RUN STG 12
OUT: 123.0F(129)
HTR: POSTPURGE
OUT: 127.4F(129)
HTR: Standby
OUT: 124.7F(129)
HTR: Standby
OUT: 122.9F(129)
Installation & Operation Manual
DISPLAY
Standby
Standby
Standby
55