Bryant 581C024--060, 581B036--072 installation instructions Enthalpy Changeover Set Points

581B,C

																						85		90	95	100		105	110
																						(29)		(32)	(35)	(38)		(41)	(43)
																			46
CONTROL	CONTROL POINT																4
CURVE APPROX. deg. F (deg. C)																	4
													42							80
	AT 50% RH
A	73 (23)									AIR										(27)
												40
B	70 (21)																										(%)
C	67 (19)									DRY	8														HUMIDITY
D	63 (17)							POUND		3
									36
																			75
							PER											(24)
								4
								3
				BTU																				RELATIVE
							32
																70
					30
														(21)
			28
															0
	ENTHALPY												1	0			0
		26										65				9		80
	4											(18)							70
	2																				0
	2																			6
	2									60											50
	0									(16)
	2										A											4	0
8								55
1								(13)		B														30
6
1							50
4								C
						(10)
1																										20
2			45				D
1			(7)
		40
																													0
		(4)
																													1
	35
	(2)
																			D C		B	A
																													HIGH LIMIT
																													CURVE
	35	40	45				50	55		60		65				70			75		80	85		90	95	100		105	110
	(2)	(4)	(7)				(10)	(13)		(16)		(18)				(21)			(24)		(27)	(29)		(32)	(35)	(38)		(41)	(43)
	APPROXIMATE DRY BULB TEMPERATURE--degrees F (degrees C)

C06037

Fig. 38 ---Enthalpy Changeover Set Points

The same equation can be used to determine the occupied or
maximum ventilation rate to the building. For example, an output				N1		EXH	TR	TR1
of 3.6 volts to the actuator provides a base ventilation rate of 5%				N		Set
					2V	10V
and an output of 6.7 volts provides the maximum ventilation rate
					EXH		24	24 Vac
of 20% (or base plus 15		cfm per person). Use	Fig. 37 to	P1
							Vac	COM
determine the maximum setting of the CO2 sensor. For example,				P		Min	HOT	_
a 1100 ppm set point relates to a 15 cfm per person design. Use				T1		Pos	+
					Open
the 1100 ppm curve on Fig. 40 to find the point when the CO2				T
sensor output will be 6.7 volts. Line up the point on the graph						DCV	1	2
with the left side of	the	chart to determine that	the range			Max
					2V	10V
configuration for the	CO2	sensor should be 1800	ppm. The
				AQ1	DCV			5
EconoMi$er IV controller will output the 6.7 volts from the CO2
				AQ		DCV
sensor to the actuator when the CO2 concentration in the space is								4
				SO+		Set	3
at 1100 ppm. The DCV set point may be left at 2 volts since the				SO	2V	10V
CO2 sensor voltage will be ignored by the EconoMi$er IV							EF	EF1
				SR+	Free
controller until it rises above the 3.6 volt setting of the minimum					Cool
				SR	B	C
position potentiometer.					A	D
Once the fully occupied damper position has been determined, set
the maximum damper demand control ventilation potentiometer					Fig. 39 ---EconoMi$er IV Control			C06038
to this position. Do not set to the maximum position as this can

result in over-ventilation to the space and potential high-humidity levels.

24