YHJF - Heating: High Electric Bill

York Heat Pumps: YHJF

Re: Heating - High Electric Bill

When the customers reports an electric bill that is much higher than normal, that typically means that the auxiliary heaters are operating more than normal.

► The blower and auxiliary heaters are typically working normally or the customer would also be experiencing no heat.

CHECKOUT:

1. Check Unit Status & Power

• Unit Status
  • Inspect the outdoor unit and make sure the outdoor coil is not frozen-over = Defrost Problem
  • Unit Operating → Step 2. Check Compressor Operation
• Power
  • Disconnect power to O/D unit by pulling disconnect or turning off breaker.
  • Open the electrical compartment cover. 
  • Inspect for burnt wiring or burnt contactor contacts.
  • Re-apply power to the unit.
  • Check for 200 - 240VAC power on the contactor inlet.
    • No Power = Tripped Breaker or Bad Wiring
  • Check for 24VAC between "R" and "C" on the defrost control board.
    • No Power = Blown Low Voltage Fuse or Bad Transformer
  • Set the Thermostat to call for heat.
  • Check for 24VAC between "Y" and "C" on the defrost control board.
    • No Power = No Call from the Thermostat ⇒ Check Thermostat
    • Power + No Operation = Anti Short-Cycle Delay or Unit in Lockout
      • Jump the "Test" pins to see if the unit starts
        • Unit Starts → Step 2. Check Compressor Operation
        • Doesn't Start → Article: YHJF/YHJD - Contactor Won't Energize

2. Check Compressor Operation

• Re-Apply Power to the unit (if turned off from previous step).
  • Compressor and Condenser Fan start and run normally → Step 3. Check Refrigerant Pressures
  • Compressor Hums but Doesn't Run = Bad Capacitor, Locked-up Compressor, or Burnt Compressor Wiring​​​​​​​

3. Check Refrigerant Pressures

• Hook-up refrigerant gauges to the pressure ports on the unit.
  • Blue ⇔ "True Suction" Port (Not The Suction Line)
  • Red ⇔ High Pressure (either refrigerant line)
• Monitor pressures as the system operates.

• If a Liquid-Line Sight Glass is installed, observe for bubbles in the sight glass (after the system has been operating for at least 5 min.)
• Suction Pressure Issues
  • Low Suction Pressure + Normal or High Discharge Pressure + Clear Sight Glass + Expansion Valve Frosting = Bad O/D Expansion Valve 
  • Low Suction Pressure + Low Discharge Pressure + Bubbles in Sight Glass + Expansion Valve Frosting = Low Refrigerant Charge
    • Try adding refrigerant through the Low Pressure gauge.
      • Suction and Discharge Pressures should gradually increase as refrigerant is added.
      • If the Discharge Pressure increases but the Suction stays low or drops = Bad O/D Expansion Valve
• High Pressure Issues
  • Monitor pressures and temperature as the system operates.
    • If the discharge pressure exceeds Normal Range or kicks-off on Hi Pressure safety in the first 5 minutes = Refrigerant Overcharge or No Indoor Blower
  • Clear Sight Glass + High Discharge Pressure + High Suction Pressure = Overcharged
  • Clear Sight Glass + High Discharge Pressure + Low Suction Pressure = Bad Expansion Valve
  • Bubbles in Sight Glass + High Discharge Pressure = Low Indoor Heat Transfer → Step 5. Check Air Temperature Rise

4. Check Compressor Discharge Temperature

• Use a multi-meter to check the temperature of the compressor discharge line.
• Normal Temperature = 120 - 150 deg.
  • Low Discharge Temperature = Inefficient Operation
  • High Discharge Temperature = Low Refrigerant Charge or Underfeeding Expansion Valve

5. Check Air Temperature Rise

• Remove "W1" and "W2" form the air handler terminal block.
• Check the Return Air Temperature near the unit or in the filter compartment.
• Check the Supply Air Temperature.
  • Normal Temperature Rise = 15-20 deg.
    • Abnormally Low Return Air Temperature ⇒ Check Return Ductwork for Cold Air Infiltration
    • Low Temperature Rise = Inefficient Operation
    • High Temperature Rise = Low Airflow
  • RE-HOOK "W1" AND "W2" WIRES ON THE AIR HANDLER!

6. Check Thermostat Aux Settings (New VisionPro 8000)

• Check the Aux Heat Control Setting
  • Under Installer Setup, go to Setup #309
    • Change from "comfort" to "2.0" or "3.0"
  • Press Done to save changes.
    • This change doesn't allow Aux Ht operation unless the indoor temperature drops [#309] degrees below setpoint.