IBC V-10, Руководство по эксплуатации

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OPERATING INSTRUCTIONS
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V-10 TOUCH SCREEN BOILER CONTROLLER
1.6.4 - Heating
The heating cycle lasts until the Heating Enabled state ends (for all loads) or
until water temperature exceeds the target temperature by 1/2 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 1.7.1.
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.
1.6.5 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.
The boiler can also enter the Circulating mode during transition from any high
temperature load (e.g. DHW at 180°F) to the cooler target (e.g. radiant floor on
outdoor reset, at perhaps 90°F). In the case where the boiler loop temperature
is outside the applicable differentials, the burner will shut off while the pump
remains on until the loop drops 1/2 the differential below the new load target
temperature.
NOTE:
if there is no place to sink heat during this type of Circulating
Mode, this phase will continue indefinitely, affecting heat delivery.
Thermal shock avoidance is key. Wherever two or more loads are used and
settings could permit supply temperature differences greater than 20°F, external
3-way motorized mixing valve, thermostatic mixing valve, or injection mixing is
recommended.
A thermal shock avoidance routine is employed to avoid undesirable effects of
large temperature swings: the hot load pump remains on until the boiler’s return
water sensor detects temperature stability - to sink excess heat. For example,
upon satisfaction of a DHW call the DHW load pump will remain running until the
boiler return water temperature falls to the DHW tank target temperature. This
deposits legacy heat from the primary loop into the water tank before activation
of a cooler load.
Always ensure that loads sensitive to high temperatures are protected using
appropriate means - e.g. a three way mixing valve set to restrict entering water
temperature to 130°F.