Check Heating Operation - Aprilaire 8570 Safety & Installation Instructions

8. CHECK HEATING OPERATION

Notes:
• To avoid the minimum on and off times during system
checkout, always start and end the check out
procedure in the OFF mode.
• Do not operate heat pumps in the heating mode at high
outdoor temperatures for extended periods of time.
1. Set the thermostat to the OFF mode.
Single/Multi Multi Multi
HP/HC HC HC
Configuration
Settings
Elect/Gas Elect Gas
Aux. Ht. Stages
W1 W1
1st Stage Heat
G
W1 W1
2nd Stage Heat W2 W2
Outputs
G
Energized
3rd Stage Heat
2. Set the thermostat to the HEAT mode.
• With the O/B configuration setting in the B position (ON), the
O/B terminal will be on in the Heat mode. In the O position
(OFF), the O/B terminal will not be on in the Heat mode.
3. Raise the temperature setting above the room temperature to
activate the desired stages of heating. The mode display will
change from "HEAT MODE" to "HEATING", which will flash,
when the thermostat is calling for heat. Fifteen (15) seconds
must elapse between each stage. Verify the correct outputs
are on according to the configuration settings shown below:
Single Single Multi Multi Single
HC HC HP HP HP
Elect Gas Elect Gas Elect
1 2
W1 W1 Y1 Y1 Y1 Y1
G G G G G
W1 W1 Y1 Y1 Y1 Y1
W2 W2 Y2 Y2 W1 W1
G G G G G
Y1 Y1
Y2 W1
W1 W1 W2
G G G
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TROUBLESHOOTING – HEATING OPERATION
Symptom
Thermostat does not call for heat
Heating does not come on at all
Auxiliary Heat does not come on
Single
HP
Fan stays on after heat call
Gas
1 2
Y1 Y1
Fan comes on before heat starts, or
G G
Fan does not come on with heat
W1 W1
Cooling comes on instead of heat
W1
W2
Takes longer than 15 seconds for auxiliary
heat to come on after compressor heat.
Cause
Minimum-off times. Change the mode to OFF first, then change the mode to
HEAT and make a call for heat.
RH terminal not connected – see wiring diagrams.
Heating equipment power not on.
High Balance point limit – set balance point to OFF during system checkout.
Number of Auxiliary Heat stages not set correctly. See Step 4 of Thermostat
Start Up (page 27).
Furnace plenum sensor keeps fan on – normal.
Blower Extension for humidifier operation. Verify that the message
"HUMIDIFYING" appears at the message center, alternating with the time
and date and any other currently active messages.
Change position of ELECT/GAS dip switch – ELECT for electric heat systems
(fan on with heat call) or to GAS for fossil fuel systems where the fan is
controlled internally by the heating equipment.
O/B dip switch not set properly. See Step 2, page 30.
Miswiring – check wire colors at thermostat and HVAC equipment.
SINGLE/MULTI dip switch set incorrectly – set to SINGLE for single-stage
compressor systems.
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