Aprilaire 1180, 1150, 1160 Installation, Outdoor Temperature Compensation, Verify Control Type

FIGURE 1 – Modulating Control Output
		PROPORTIONAL
		CONTROL BAND	Note:
	10 VDC
			The Proportional
			Control Band
OUTPUT			can be adjusted
			to 6%, 9%, 12%,
	5 VDC		or 15% RH. The
			factory setting
			of 12% is
			depicted at left.
	0 VDC
	-6	0	+6
	MEASURED %RH - SETPOINT %RH

90-890

As an example, using the 12% proportional band (factory-setting), when the measured RH is 6% above the set-point the output will be 0 VDC; when the measured RH is 6% below set-point the output will be 10 VDC; when the measured RH is 3% below set-point the output will be approximately 7.5 VDC. The humidifier uses this varying signal to time-proportion the operation of the heating elements in the tank. 10 VDC output corresponds with 100% humidifier capacity, 5 VDC with 50% capacity, etc. Modulating control will result in a more precise control of relative humidity.

OUTDOOR TEMPERATURE COMPENSATION

AUTOMATIC MODE

The automatic mode is the preferred method when the application requires that the Control automatically adjust the RH set-point based on the outdoor temperature. This is recommended for all comfort-based applications such as office buildings, schools, day cares, etc. It is also recommended for any application where the primary concern is to avoid the potential for condensation that can form on areas within the building such as windows and within walls. When installed in this mode, the Control utilizes an Outdoor Temperature Sensor that will track the actual outdoor temperature. The Control then automatically adjusts the desired indoor RH.

MANUAL MODE (SPECIFIC SET-POINT CONTROL)

The manual mode is the preferred method when the application requires that a specific set-point be maintained regardless of the outdoor temperature. This is recommended for all process-based applications such as print shops, book stores, test facilities, etc.

When installed in this mode, the Outdoor Temperature Sensor is replaced with a “manual” resistor case that prevents the Control from adjusting the space RH set-point based on the outdoor temperature, and controls to the specific set-point selected on the Control.

Note: If the building is not designed to handle the amount of RH the humidifier is supplying, the building occupants may need to adjust the RH setting on the Control to a lower value during extreme days to prevent condensation on interior surfaces. The RH setting should be adjusted upward when the outdoor temperature goes up.

INSTALLATION

CAUTION Improper jumper settings may damage humidifier.

The shunt on the JP2 header pin must be set in accordance with the instructions in this manual.

STEP 1: VERIFY CONTROL TYPE

When shipped with a Steam Humidifier, the Automatic Steam Humidifier Control is preset at the factory to match the humidifier model: Model 1150 Steam Humidifier is configured for on/off control while the Model 1160/1180 Steam Humidifier is configured for modulating control. When shipped as a replacement (Model 57), the Control is preset for use with a Model 1150 (i.e., on/off control). If using the Model 57 with a Model 1160 or 1180, the ‘control type’ setting must be changed for modulating control. See below.

Remove the door to the Automatic Steam Humidifier Control and look at the area on the circuit board above the terminal block. The three-pin header labeled JP2 should be set in the following manner:

For the Model 1150, the Control must be set to the on/off configuration. The shunt must be placed on the 2 & 3 pins. See Figure 2.

FIGURE 2 – On/Off Setting for Model 1150
9	12				R17
6		15			1 2 3
					JP2
	I+	I-	24V	C	H+ H-	ODT
						90-891

For the Model 1160 or 1180, the Control must be set to the modulating configuration. The shunt must be placed on the 1 & 2 pins. See Figure 3.

FIGURE 3 – Modulating Setting for Model 1160 or 1180
9	12				R17
6		15			1 2 3
					JP2
	I+	I-	24V	C	H+ H-	ODT
						90-892

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