IBC V-10, Operating Instructions Manual

Page: 17 / 36

13
OPERATING INSTRUCTIONS
V-10 TOUCH SCREEN BOILER CONTROLLER
1.6.1 Standby
Waiting for a Heating Enabled signal (as defined in the above glossary), the
burner and boiler pump are off during this time.
1.6.2 Purging
PREPURGE
On a Heating Enabled signal, the boiler automatically enters a prepurge cycle.
The fan starts and automatically adjusts to a level suitable for ignition. Ten
seconds later, the pump starts. After a total of 15 seconds, the ignition cycle
begins.
INTERPURGE
The boiler enters an interpurge cycle if ignition is unsuccessful. The fan and
pump continue to run, and ignition is delayed by an additional 15 seconds.
POSTPURGE
When the boiler exits a heating cycle the fan remains on for 20 seconds and then
reduces airflow to an ultra-low flow mode for 90 minutes unless preempted.
The boiler pump and the last load pump remain on for 5 minutes (adjustable)
after the Heating cycle ends.
If the heating cycle ends as a result of water temperature exceeding the
postpurge will continue as normal but the boiler will enter the circulating mode.
(Current boiler target water tempe 1/2 the Supply Differential.)
The cut off temperature levels are specific for each load; for space heating they
are determined using the preset target plus 1/2 of the Supply Differential setting.
Default values for such differentials are 20°F (+/- 10°F) for space heating with
outdoor reset and 20°F ( +/- 10°F) for DHW.
If there is a Heating Enabled signal any time during this cycle, the postpurge
ends and a prepurge begins, otherwise the boiler will enter Standby mode.
1.6.3 Ignition
After the prepurge, the gas ignitor starts sparking and the valve opens for a 4.0
second ignition trial.
If no flame is detected at the end of the trial, the interpurge cycle is entered. If
3 trial for ignition sequences fails, the boiler locks out for a 1 hour long interval,
after which the ignition cycle is refreshed (e.g. For 3 further attempts). Alternately,
the Clear Errors diagnostic button can be used to accelerate the retry sequence.
The homeowner should follow up persistent recurrence of the 1 hour reset
routine by contacting a qualified service technician, to evaluate the cause of such
ignition irregularity.
With a successful ignition, the output of the boiler decreases to a low level after
7-10 second burner warmup period and the heating cycle begins.