IBC Technologies SL 30-175, Инструкция по установке и эксплуатации

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2-5
BOILER SYSTEMS AND OPERATION
SL 30-175, SL 45-260 MODULATING GAS BOILERS
the pump remains on for 5 minutes (adjustable) after the heating cycle ends.
if the heating cycle ends as a result of water temperature exceeding the load
specific band limit, the postpurge will continue as normal, but the boiler will enter
the circulating mode.
The cut off temperature levels are specific for each load; they are determined
using the preset target plus ½ of the supply differential entered. default values
for such differentials are 20°F (+/- 10°F) for space heating with outdoor reset and
16°F ( +/- 8°F) for dHW and other set point loads,
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.
2.5.3 Ignition
after the prepurge, the gas valve opens for 4.0 seconds.
If no flame is detected at the end of the trial, the
interpurge cycle is entered. if
ignition fails 3 times successively, 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 boiler can be powered down and restarted to accelerate the re-try 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 immediately to a low
level, and the heating cycle begins.
2.5.4 Heating
the heating cycle lasts until the
Heating Enabled
state ends, or until water
temperature exceeds the target temperature by ½ of the supply differential for the
last served load and the throttle has fallen to the minimum output. at the end of
the heating cycle, the boiler enters a postpurge.
During the heating cycle, the boiler addresses the multiple defined loads
in accordance with its Prioritization algorithm. see Section 2.6.1 . Boiler
output changes to meet heating demands as indicated by the temperature
characteristics of the boiler supply and return water. Boiler supply water
temperature targets vary according to the set up parameters entered, and are
subject to further variation for loads where outdoor reset has been selected.
Where thermal loads are within the boiler’s minimum to maximum MBH throttle
range, the control algorithm seeks to regulate the boiler supply temperature
within ±3°F of the target temperature. on/off differentials apply to loads below
the minimum MBH input rating.
2.5.5 Circulating
this cycle operates when water temperature exceeds target by 1/2 of the supply
differential for that load at minimum output, and call for heat is still present. after
entering a postpurge , the system pump remains on until water temperature is
1/2 of the supply differential below setpoint temperature.
in a two load system, Circulating mode will also run during transition from any
high temperature load (e.g. dHW at 180°F) to the cooler target (e.g. baseboards
on outdoor reset, at perhaps 130°F). in the case where the boiler loop
temperature is outside the applicable differentials, the burner will shut off while