Rheem was founded in California in 1925 and today builds air conditioners, gas furnaces, heat pumps and water heaters, with Ruud as its sister brand. In Novato, San Rafael and Larkspur homes, a Rheem system that has stopped keeping up usually shows one of a few symptoms: temperatures that wander, strange noises, weak airflow or a power or gas bill that has crept up. Behind them are a short list of causes, and on hybrid systems one more: a control that is not switching between the heat pump and the furnace the way it should.
Hybrid (dual-fuel) systems
A Rheem hybrid system pairs a heat pump with a gas furnace. The heat pump handles cooling and most heating; the furnace takes over when the outdoor temperature drops below a set point, or when the heat pump cannot keep up. In a mild winter climate, the heat pump can carry a large share of the heating.
When a hybrid system misbehaves, we check in this order:
- The switchover setting. If it is set too high, the furnace runs on days the heat pump could handle. Too low, and the heat pump struggles on the coldest mornings.
- The outdoor temperature sensor. A failed or misplaced sensor tells the control it is colder or warmer than it is.
- Thermostat configuration. The thermostat or control has to be set up for dual fuel; set up as a plain heat pump with backup, it can run both at once or neither.
- Heat pump lockouts. A heat pump that has shut itself down on a pressure or temperature fault leaves the furnace doing all the work, and the house still feels fine until the bill arrives.
- The equipment itself. Then the usual heat pump and furnace checks: defrost, reversing valve, ignition, flame sensing, limits.
Airflow: filters and duct obstructions
Inadequate airflow is a common Rheem complaint, and it usually has a mechanical cause rather than an electronic one. A clogged filter, a dirty indoor coil, a collapsed flex duct or a blocked return all reduce the air moving across the coil. In cooling, the coil can freeze; in heating, the furnace overheats and trips its limit, and a heat pump’s pressures climb. We measure static pressure and temperature change across the equipment to find where the air is being lost. A thorough cleaning or a duct fix often restores a system that seemed underpowered; see poor airflow and duct repair.
Thermostats
A thermostat that reads the wrong temperature, has lost its settings or has a loose wire disrupts temperature control on any system, but especially on a hybrid one, where the thermostat may be the part deciding which heat source runs. We test the thermostat and its wiring before replacing it, and if it does need replacing, thermostat installation covers matching it to the equipment.
Strange noises and rising bills
| What you notice | Common cause | What it usually takes |
|---|---|---|
| Buzz or hum from the outdoor unit | Capacitor, contactor or fan motor | Electrical tests, single-part repair |
| Squeal or grinding from the blower | Worn motor bearings | Blower motor replacement |
| Whoosh or rumble at furnace start | Delayed ignition or dirty burners | Burner cleaning, ignition check |
| Higher bills, same comfort | Dirty coils, low airflow, refrigerant leak, hybrid switchover set too high | Coil cleaning, airflow and charge checks |
More on bills is on our high energy bills page.
What you can expect
We are independent and not affiliated with Rheem. You get an itemized price after the diagnosis, factory certified parts that carry the manufacturer’s warranty, and a labor warranty on our work. Same-day service is usually possible when you call before noon, and a maintenance plan adds priority scheduling and repair discounts.