Goodman Mfg VC8 instruction manual Start-Up Procedure And Adjustment

START-UP PROCEDURE AND ADJUSTMENT

The cooling system manufacturer’s instructions must be checked for required air flow. Any electronic air cleaners or other devices may require specific air flows, consult installa- tion instructions of those devices for requirements.

3.Knowing the furnace model, locate the high stage cooling air flow charts in the Specification Sheet applicable to your model. Look up the cooling air flow determined in step 2 and find the required cooling speed and adjustment setting.

Example: A *MVC80704BX furnace installed with a 2.5 ton air conditioning system. The air flow needed is 1000 CFM. Looking at the cooling speed chart for *MVC80704BX, find the air flow closest to 1000 CFM. A cooling airflow of 990 CFM can be attained by setting the cooling speed to “C” and the adjustment to “-” (minus).

4.Continuous fan speed is 30% of the furnace’s maximum airflow capability.

Example: If the furnace’s maximum airflow capability is 2000 CFM, the continuous fan speed will be 0.30 x 2000 CFM = 600 CFM.

5.Locate the blower speed selection DIP switches on the integrated control module. Select the desired “cooling” speed tap by positioning switches 1 and 2 appropriately. Select the desired “adjust” tap by positioning switches 3 and 4 appropriately. Refer to the following figure for switch positions and their corresponding taps. Verify CFM by noting the number displayed on the dual 7- segment LED display.

6.The multi-speed circulator blower also offers several custom ON/OFF ramping profiles. These profiles may be used to enhance cooling performance and increase comfort level. The ramping profiles are selected using DIP switches 5 and 6. Refer to the following figure for switch positions and their corresponding taps. Refer to the bullet points below for a description of each ramping profile. Verify CFM by noting the number displayed on the dual 7-segment LED display.

Switch Bank: S4

Ramping	DIP Switch No.
Profiles	5	6
A*	OFF	OFF
B	ON	OFF
C	OFF	ON
D	ON	ON

(*Indicates factory setting)

•Profile A provides only an OFF delay of one (1) minute at 100% of the cooling demand airflow.

	100% CFM	100% CFM
OFF			OFF

1 min

•Profile B ramps up to full cooling demand airflow by first stepping up to 50% of the full demand for 30 seconds. The motor then ramps to 100% of the required airflow. A one (1) minute OFF delay at 100% of the cooling airflow is provided.

			100% CFM	100% CFM
OFF	50% CFM					OFF
		1/2 min			1 min

•Profile C ramps up to 85% of the full cooling demand airflow and operates there for approximately 7 1/2 minutes. The motor then steps up to the full demand airflow. Profile C also has a one (1) minute 100% OFF delay.

OFF 100% CFM OFF

Switch Bank: S3

Cooling	DIP Switch No.
Airflow	1	2
A	OFF	OFF
B	ON	OFF
C	OFF	ON
D*	ON	ON
(*Indicates factory setting)
Switch Bank: S3
Adjust Taps	DIP Switch No.
	3	4
Normal*	OFF	OFF
10%	ON	OFF
-10%	OFF	ON
Normal	ON	ON

(*Indicates factory setting)

•Profile D ramps up to 50% of the demand for 1/2 minute, then ramps to 85% of the full cooling demand airflow and operates there for approximately 7 1/2 minutes. The motor then steps up to the full demand airflow. Profile D has a 1/2 minute at 50% airflow OFF delay.

OFF OFF

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