American Standard UV05 manual Unit Mode Priority, Special purpose UVC unit mode priority

Description of Operation

Unit Mode Priority

The UVC uses the network variables and binary inputs listed in Table 10 and Table 11 to determine the current unit mode. Special purpose UVC unit modes have higher priority than the normal UVC unit modes as shown in the tables.

Each table lists the highest priority items on the left to the lower priority items to the right. The right-most columns indicate unit operation as a result of the left-most columns. The term “Don’t care” in these tables implies that another network variable or binary input to the left has a higher priority.

Table 10: Special purpose UVC unit mode priority

				Priority result
Emergency override	Remote shutdown	Energy hold	Energy hold	Unit mode	Actual UVC action
input1	binary input	off input1	off output2	output2
	De-energized4	Normal	Normal	See	the normal
Normal3				UVC mode priority (Table 11)
		Energy hold off	Energy hold off	Off	Off
	Energized5	Don’t care	Energy hold off	Off	Off
Pressurize	Don’t care	Don’t care	Don’t care	Off	Pressurize
De-pressurize	Don’t care	Don’t care	Don’t care	Off	De-pressurize
Purge	Don’t care	Don’t care	Don’t care	Off	Purge
Shutdown	Don’t care	Don’t care	Don’t care	Off	Off

1.Network input.

2.Network output.

3.Normal indicates the UVC power-up condition.

4.De-energized indicates that the contacts connected to this binary input are open.

5.Energized indicates that the contacts connected to this binary input are closed.

Table 11: Normal UVC mode priority

		Priority result
Application override	Unit mode override	Unit mode output 2
input 1	input1
	Normal (Auto)3	Heat
		Cool
		Emergency heat
Normal (Auto)3	Heat	Heat
	Cool	Cool
	Night purge	Night purge
	Off	Off
	Emergency heat	Emergency heat
	Fan only	Fan only
Heat	Don’t care	Heat
Cool	Don’t care	Cool
Night purge	Don’t care	Night purge
Off	Don’t care	Off
Emergency heat	Don’t care	Emergency heat
Fan only	Don’t care	Fan only

1.Network input.

2.Network output.

3.Normal (Auto) is the normal UVC power-up state.

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