Lochinvar EcoShield Series, Инструкции по установке, пусконаладке и обслуживанию

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12.3 SEQUENCE OF OPERATION
OPERATION DISPLAY
1.
Upon a call for heat, the control turns on the appropriate
pumps. WHR: Standby
OUT: 61.4C (65)
2.
The control connects 230 VAC to the fan. The fan does
not run at this time.

If the unit is equipped with a flow switch or low
water cut-off, it must close before the control
powers up the fan.

If the unit is equipped with a manual reset high
limit it must be closed before the control powers
up the fan.
 If the unit is equipped with a gas pressure switch,
it must close at this time.

If there is an auxiliary device connected to the
unit, the unit will then provide 24 VAC to its enable
relay. If the auxiliary device has a proving switch,
it must close before the sequence continues.
WHR: Standby
OUT: 61.4C (65)
3.
The control then starts a 10 second prepurge cycle.
WHR: PREPURGE
OUT: 61.5C (65)
4.
Once the prepurge cycle is complete, and the blocked
drain and auto-reset high limit are closed, the control
starts the 5-second trial for ignition by sending spark
voltage to the spark electrode and opening the gas
valve.
WHR: IGNITION
OUT: 61.5C (65)
5.
If the control does not detect flame by the end of the
trial for ignition, the control performs a 10 second
postpurge. On the SHW45-325CE to SHW115-435CE
models, the control will perform another prepurge and
will try to light the burner again. If the burner does not
light after 4 trials, the control will lockout for 1 hour and
then try another set of 4 trials. On the SHW145-435CE
the unit will lockout until manually reset.
WHR: POSTPURGE, PREPURGE
OUT: 61.5C (65)
6.
If the control detects a flame before the trial for ignition
ends, it begins to modulate the burner in order to
maintain the set point.
WHR: RUN 20% RATE
OUT: 62.6C (65)
7.
Once the call for heat is satisfied, the control will turn off
the burner. The fan will remain on for the 10-second
postpurge cycle. The primary pump will continue to run
for its respective pump delay time, and then turn off.
WHR: POSTPURGE
OUT: 64.5C (65)
8.
Primary pump switches off.
WHR: Standby
OUT: 64.8C (65)