York Heat Pump: YorkGuard VI
Re: Aux Heat Stuck On
►The auxiliary heaters stick on and the customer reports overheating of the controlled space.
The Yorkguard VI board controls Aux Heat operation through the W1-Out and W2-Out terminals.
Balance Point
If the outdoor ambient temperature is less than the Balance Point setting and above LTCO and a W input is received with a Y1 input, the control will energize the compressor contactor output based on the Y1 input and will energize the W1-Out immediately when the W input is received.
When the W input is received, the control will start a fifteen-minute timer. If the call for Y1 + W is still present after the fifteen-minute timer expires, the control will then energize W2-Out along with W1-Out.
LTCO
If the outdoor ambient temperature is below the LTCO setting, the control will de-energize the compressor and energize W1-Out immediately when a Y1 input is received. W2-Out will act as 2nd stage heat and be energized on a call for W.
Defrost
The control will energize W1-Out 30 second prior to and during defrost operation. If W1-Out has been energized for 15 minutes W2-Out will be energized also. The W1-Out and W2-Out will remain energized (depending on the 15 minute timer) 180 seconds after the defrost cycle has been terminated.
Qty | Possible Causes: |
2 | Mis-Wired Low Voltage |
Bad Heat Relay | |
Low Voltage Short | |
Bad YorkGuard Module |
CHECKOUT:
1. Check Thermostat
Stat | A/H | H/P |
R | R | R |
C | C | C |
O | O | O |
G | G | - |
W | - | W |
Y1 | Y1 | Y1 |
Y2 | - | Y2 |
- | W1 | W1 OUT |
W2 | W2 OUT | |
Y2 | Y2 OUT | |
L | - | X/L |
► Placing a jumper between "W" and "W1-OUT" or "W2-OUT" (at the air handler or heat pump) WILL CAUSE THE AUX HT TO STICK ON!