Heat Pump Not Heating in Piedmont

Heat Pump Not Heating in Piedmont

Piedmont is largely older estate homes in the Oakland hills, and many of them were built for heat, never for cooling. A lot of the heat pumps here are recent retrofits dropped into houses with original ductwork that was sized for an old gravity furnace. That history matters when the heat pump stops heating, because the failure is often in the controls, the airflow, or undersized ductwork choking the indoor coil, not in a brand-new outdoor unit.

The Oakland-hills climate is mild, cool but well above freezing most winter nights, so a heat pump covers both the heating these homes have always needed and the cooling owners increasingly add, without any strain from the weather. On a multi-story Piedmont house the system is usually zoned, because the top floor runs hot and the ground floor cold otherwise. So a no-heat call here frequently comes down to a zone control fault or a stuck damper on a multi-story plan, alongside the usual reversing-valve, refrigerant, and electrical failures.

We look at the whole retrofit, the equipment, the controls, and the ducts it was tied into, before deciding what failed. The diagnostic fee credits toward the repair on most jobs.

Common causes

Zone control fault on a multi-story plan. Most multi-story Piedmont homes are zoned to balance the floors, and a zone board fault or a damper stuck closed can leave the top floor warm and the ground floor cold, or drop heat to one level entirely. We read the zone board outputs and test each damper actuator to find which one lost the call, then repair the control rather than the equipment.

Undersized ductwork starving the indoor coil. When a heat pump was tied into original ductwork sized for an old gravity furnace, restricted airflow over the indoor coil cuts heating output and can trip the system on temperature. We measure static pressure and airflow to confirm the ducts are the bottleneck, and recommend the duct correction rather than chasing a refrigerant problem that is not there.

Stuck reversing valve. The reversing valve flips the system into heating, and a failed solenoid or stuck valve leaves it running in cooling, blowing unheated air. We meter the solenoid and read line temperatures to confirm the valve actually shifted into heating before replacing it.

Low refrigerant charge. A heat pump low on refrigerant loses heating capacity first. On a recent retrofit the leak is often at a fitting on the new line set. We find it with electronic detection, repair it, and weigh in the correct charge instead of topping off and leaving the leak in place.

Contactor or capacitor failure. A failed contactor or weak start capacitor takes the outdoor unit offline, so the indoor side blows unheated air. These are common, inexpensive failures we carry on the van. We meter the capacitor and inspect the contactor before looking further.

How we diagnose it

• We determine whether the whole house lost heat or only one floor or zone on a multi-story plan.
• Zone board outputs get read and damper actuators tested to rule out a stuck-closed damper.
• Static pressure and airflow get measured to see if undersized original ductwork is choking the coil.
• Line temperatures confirm the reversing valve shifted into heating.
• We check refrigerant charge and inspect the contactor and capacitor on the outdoor unit.

$75 diagnostic, credited toward any repair over $200. You get a written quote before any work begins.

Heat Pump Not Heating in Piedmont: common questions

Nearby and related

Heat Pump Not Heating near Piedmont: Oakland · Berkeley · Alameda .

This is usually a heat pump installation & service in Piedmont job. See our heat pump installation & service overview or the Piedmont service area.