Unit Startup - York YACT038-072 Installation Manual

AFFINITY COMBINATION INSTALLATION MANUAL

Unit Startup

Before powering unit, check the
following:
• Fuses, breakers and wire size are correct and match the
name plate.
• Low voltage wiring is complete.
• Black/white and gray/white wires in unit control box
have been removed if auxiliary heat has been installed.
• DIP switches are set correctly. SW3-3 must be in "OFF"
position.
• Piping has been completed and the water system is
cleaned and flushed.
• Air is purged from the closed loop system.
• Air is purged from buffer tank, hydronic system isolation
valves are open, and water control valves or loop pumps
are wired.
• Condensate line is open and correctly pitched.
• Blower rotates freely and foam shipping support has
been removed.
• Blower speed is correct (DIP switch setting).
• Air filter is clean and in position.
• Service/access panels are in place.
• Return air temperature is between 60-80°F in heating
and 70-95°F in cooling.
• Air coil is clean.
Hydronic Startup Instructions
1. Initiate a control signal to place the unit in the hydronic
heating mode. Heating setpoint must be above the
water temperature of the buffer tank and/or load side
water loop.
2. Be sure that the water control valve or loop pumps
are activated.
3. The compressor and load side circulating pump will
energize after a time delay.
4. Using a digital thermometer measure the load side water
entering the unit.
NOTE: Ensure that the sensing probe is in contact with
copper piping and that it is well insulated to prevent
measurement errors due to ambient room temperature.
Allow 2-3 minutes before measurement for best results.
5. Using a digital thermometer, measure the load-side
water temperature leaving the unit. Refer to Operating
Parameters table and compare measured temperature
rise with data.
6. Adjust the heating setpoint below the water temperature
of the buffer tank and/or load side water. Verify that
the compressor, load side circulating pump and water
control valve or loop pumps deactivate.
7. During test, check for excessive vibration, noise or water
leaks. Correct or repair as required.
8. Set system to desired normal operating temperature to
maintain desired comfort level.
9. Instruct the owner/operator in the proper operation of the
hydronic temperature control and system maintenance.
Forced Air Startup Instructions
NOTE: On initial power-up a four-minute time delay
will occur.
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 setpoint must be set below
room temperature.
3. First stage cooling will energize after a time delay.
4. Be sure that the compressor and water control valve or
loop pumps are activated.
5. Verify that the water flow rate is correct by measuring
the pressure drop through the heat exchanger using the
P/T plugs
and comparing to water Pressure Drop table.
6. Check the temperature of both the supply and discharge
water. Refer to Operating Parameters tables.
7. Check for an air temperature drop of 15° to 25° F across
the air coil, depending on the blower speed and entering
water temperature. Refer to Operating Parameters tables.
8. Adjust the cooling setpoint above the room temperature
and verify that the compressor and water valve or loop
pumps deactivate.
9. Initiate a control signal to place the unit in the
heating mode. Heating setpoint must be set above
room temperature.
10. First stage heating will energize after a time delay.
11. Check for an air temperature rise of 20° to 35° F across
the air coil, depending on the blower speed and entering
water temperature. Refer to Operating Parameters tables.
12. If auxiliary electric heaters are installed, adjust the heating
setpoint until the electric heat banks are sequenced on.
All stages of the auxiliary heater should be sequenced on
when the thermostat is in the "Emergency Heat" mode.
Check amperage of each element.
13. Adjust the heating setpoint below room temperature
and verify that the compressor and water valve or loop
pumps deactivate.
14. During all testing, check for excessive vibration, noise or
water leaks. Correct or repair as required.
15. Set system to desired normal operating mode and set
temperature to maintain desired comfort level.
16. Instruct the owner/operator in the proper operation of
the thermostat and system maintenance.
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