York Heat Pump Runs Constantly: Causes, Fixes & Costs

Last updated Oct 19, 2026 · By fixme.vip Editorial

York heat pump runs constantly: what it means

“Runs constantly” is a symptom, not a stored fault code. York heat pumps don’t flash a specific code for it. The system either never satisfies the thermostat, or it keeps running after the thermostat stops calling.

These are two different problems, and telling them apart matters:

• The thermostat is calling but the house never reaches setpoint. This is usually a capacity, airflow or refrigerant issue.
• The thermostat is satisfied or off, but the outdoor unit keeps running. This is an electrical control fault, usually a welded contactor or a thermostat or wiring short. It needs prompt service.

Note that long run times are designed behavior on York variable-speed and inverter models. They’re also normal on any heat pump in very cold or very hot weather.

There’s nothing to reset because there’s no lockout. The behavior continues until the cause is fixed.

Some problems overlap with this one and have their own pages (see Related codes):

• Heat that comes only from the backup strips: York Heat Pump Aux Heat On Constantly: Causes & Fixes
• Ice buildup on the outdoor coil: York Heat Pump Ice on Outdoor Unit: Causes & Fixes
• Weak heat output overall: York Heat Pump Not Heating: Causes, Fixes & Costs

York heat pump runs constantly: common causes, ranked by probability

1. Dirty air filter or restricted airflow. Closed registers, a blocked return or a dirty indoor coil cut capacity, so the unit can’t keep up.
2. Thermostat setup or placement. Common culprits are:
   • A setpoint that’s too aggressive
   • The fan set to ON rather than AUTO, so the indoor fan never stops. The blower runs continuously even while the compressor cycles on and off normally. This is a different symptom from a compressor that won’t cycle off.
   • The wrong system type configured
   • A thermostat in a drafty or sunny spot
   • Dying batteries
3. Extreme outdoor temperatures. The unit is near or below its balance point, so it’s working as designed but undersized for the weather.
4. Low refrigerant charge from a leak. This reduces capacity in both heating and cooling.
5. Dirty or blocked outdoor coil. Debris, vegetation or a snow or ice buildup on the coil can all cause it.
6. Welded or stuck contactor in the outdoor unit. The compressor and fan run even with the thermostat off.
7. Thermostat wiring short or a faulty thermostat. The Y signal stays energized.
8. Reversing valve or defrost control problems. The valve may be partially shifted or leaking internally, or the board may be misreading its sensors. Behavior varies by board.
9. Duct leakage or poor insulation. Conditioned air is lost to the attic or crawlspace.
10. Undersized equipment. This is common after additions or remodels.

How to fix York heat pump runs constantly: safe checks first

• Thermostat:
  • Confirm the mode (HEAT or COOL) and a reasonable setpoint.
  • Set the fan to AUTO.
  • Replace the batteries.
  • Check that the thermostat isn’t near a lamp, a sunny window, a supply register or an exterior door.
• Test for a stuck contactor: Set the thermostat to OFF and wait about 5 minutes. If the outdoor unit is still humming and its fan is spinning, switch it off at the outdoor disconnect or breaker and call a technician. Don’t keep restoring power.
• Air filter: Replace it if it’s dirty. Note the size printed on the frame.
• Vents and returns: Open the supply registers and clear furniture and rugs away from them and from the return grilles.
• Outdoor unit:
  • From the outside only, clear leaves, snow and plants to about 2 feet around the unit.
  • Don’t remove the panels or spray inside the cabinet.
  • Make sure the access panels are seated.
• Breaker: If a breaker has tripped, reset it once. If it trips again, leave it off and call a pro.
• Condensate: Check that the indoor drain line isn’t backed up or overflowing into the pan. In cooling, a clog can trip a float switch. That cuts the cooling call, so it causes shutdowns or short cycling rather than constant running.
• Weather check: If it’s below about 25–30°F, long run times are often normal. Watch whether the house holds temperature.

How a technician will diagnose it

A good technician will typically take these steps:

1. Confirm the control signal. They’ll check the thermostat output (Y and O/B) at the air handler and at the outdoor unit. A voltage reading separates a stuck contactor from a thermostat or wiring fault.
2. Inspect the contactor. They’ll look for pitted, welded or bug-blocked contacts that stay closed when de-energized.
3. Measure airflow. This includes static pressure, the condition of the indoor coil and blower, and blower speed taps or settings.
4. Check the refrigerant charge. They’ll use gauges plus superheat and subcooling readings against York’s charging chart. If the charge is low, leak detection should follow. Don’t accept a “top-off” without a leak search.
5. Check temperature split. They’ll measure the supply and return temperatures to verify capacity.
6. Check the reversing valve and defrost board. They’ll compare line temperatures, check the solenoid and confirm the defrost sensor and board operation according to the model’s service manual.
7. Run a load and duct assessment if the equipment checks out mechanically but still can’t keep up.

Symptom, cause and what to do

York heat pump runs constantly repair cost

Prices vary by region and warranty status. York’s parts warranty often covers parts like the board, coil and valve on registered units, but labor is usually extra.

Related codes

• York Heat Pump Aux Heat On Constantly: Causes & Fixes
• York Heat Pump Not Heating: Causes, Fixes & Costs
• York Heat Pump Not Cooling: Causes, Fixes & Costs
• York Heat Pump Frozen, Not Defrosting: Causes & Fixes
• York Heat Pump Ice on Outdoor Unit: Causes & Fixes
• York Heat Pump Stuck in Defrost Mode: Causes & Fixes
• York Heat Pump Short Cycling: Causes, Fixes & Costs
• York Furnace Runs Constantly But Not Enough Heat: Fixes