Unit startup, Before powering the unit, check the following, Startup steps – WaterFurnace Envision (XL) User Manual

Page 38

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ENVISION 7-25 TONS INSTALLATION MANUAL

39

Unit Startup

Before powering the unit, check the following:

• High voltage is correct and matches nameplate

• Fuses, breakers and wire size are correct

• Low voltage wiring is complete

• Piping has been completed and water system cleaned and flushed

• Air is purged from closed loop system

• Isolation valves are open and water control valves or loop pumps wired

• Condensate line is open and correctly pitched

• Transformer has been switched to lower voltage tap if needed

• Blower rotates freely

• Blower speed is correct

• Air filter is clean and in position

• Service/access panels are in place

• Return air temperature is between 60°F-80°F in heating and 70°F-95°F in cooling

• Air coil has been cleaned

Startup Steps

1. Initiate a control signal to energize the blower motor. Check blower operation.

2. Initiate a control signal to place the unit in the cooling mode. Cooling set point must be set below room temperature.

3. First stage cooling will energize after a time delay. Check for correct rotation of scroll compressors in 120, 080, 095

units. Incorrect rotation will cause unusual noise and low refrigerant pressures. Switch any two power leads at the

compressor or contractor to reverse rotation.

4. Be sure the compressor and water control valve or loop pumps are activated.

5. Initiate a control signal to energize second stage cooling.

6. Second stage cooling will energize after a time delay. Check for correct rotation as indicated in step 3.

7. Verify that the water flow rate is correct by measuring pressure drop through the heat exchanger using the P/T plugs

and comparing to Water Pressure Drop Table on page 24.

8. Check the temperature of both the supply and discharge water. Refer to Unit Operating Pressures and Temperatures

9. Check for an air temperature drop of 15° to 25°F across the air coil, depending on blower speed and entering water

temperature.

10. Adjust the cooling setpoint above the room temperature and verify that the compressor and water valve or pumps

deactivate.

11. Initiate a control signal to place the unit in the heating mode. Heating setpoint must be set above room temperature.

12. First stage heating will energize after a time delay.

13. Initiate a control signal to energize second stage heating.

14. Second stage heating will energize after a time delay.

15. Check the temperature of both the supply and discharge water. Refer to Unit Operating Pressures and Temperatures.

16. Check for an air temperature rise of 20°F to 25°F across the air coil, depending on the blower speed and entering water

temperature.

17. Adjust the heating setpoint below room temperature and verify that the compressor and water valve or loop pumps

deactivate.

18. During all testing, check for excessive vibration, noise or water leaks.

19. Set system to desired normal operating mode and set temperature to maintain desired comfort level.

20. Instruct the owner/operator in the proper operation of the thermostat and system maintenance.

21. Check belt tension and readjust as necessary after first few hours.

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