Common Thermostat Functions

Your home's thermostat is the command center for your central heating and air conditioning system and it is equipped with a variety of functions. Some thermostats offer more functionality than others, yet all of them share a standard of basic functions which give the user options of air control. Many thermostats have system specific features such as Dehumidify but the focus here are common thermostat functions.

Your thermostat will be powered either by battery or hardwired to the system's 24V circuitry supplied by the furnace's or air handler's transformer. If battery operated, the thermostat will remain operational during a system or power failure but if hardwired, the thermostat could indicate a system error such as a blown fuse or tripped breaker if the screen is blank. If you recognize a problem or poor performance, set the thermostat to the off position to prevent potential damages and call Obsidian Air Solutions LLC for a professional diagnosis.

- Fan On/Auto: This option relates to the indoor fan operation only. The Fan Auto selection will circulate indoor air only during a heating or cooling cycle whereas the Fan On selection will circulate indoor air indefinitely.

- Mode: This function categorizes your system's features and allows the user to select which feature to operate be it Cool for air conditioning, Heat for warming up the house, Off for the days of window weather, or Auto for an automatic changeover between Heat and Cool for the hot days with cooler nights (if your thermostat applies).

- Temperature Up/Down (+/-): This selects the desired indoor temperature target and does not determine output air temperature.

- Hold/Run Schedule: This feature applies only to programmable thermostats and gives the user the option to operate the central air systems by running a predetermined schedule or by holding a manually set temperature target. Some thermostats allow for timers on the Hold feature while others remain indefinitely until manually changed back to Run.

- Auxillery/Emergency Heat (AUX/EMG Heat): This feature typically applies to heat pump (electric heat) systems that use a secondary source of heat via electric resistance to support the primary source (heat pump) for high demand or replace it in the event that the primary heat source fails. Some systems use electric heat as the primary source with a gas furnace as the secondary. Whichever way your system is designed, setting your thermostat to this function will bypass the primary source of heat and run the secondary only.

Your Air Filter And Why You Should Not Get Attached

The forgotten air filter... a key player in keeping max performance of airflow. Without it, your indoor furnace/air handler, evaporator coil, and ductwork will be obligated to take up the mantle of trapping dust and other particulates, layering the entirety of your airflow system with all of it. The air filter is vital to maintaining clean air, preventing the blower wheel from accruing excessive weight and snapping. Or the evaporator coil becoming clogged, restricting airflow and creating a dust sponge for moisture and bacteria to reside and more frequent drain clogs. An air filter isn't a one-time install but requires frequent replacements.

Let’s face it, this hardworking hero of your indoor air deserves a nod, not a hug! Your air filter tirelessly traps dust, dander, and the occasional rogue pet hair, but don’t start naming it or knitting it a sweater—its lifespan is more fleeting than a houseguest who overstays. Regularly swapping it out ensures your home stays fresh and your HVAC doesn’t stage a dramatic revolt. So, admire its gritty dedication from afar, and let it retire with dignity when the time comes.

Keeping your air filter changed on a regular schedule (typically every 30 days) prolongs the likelihood of a healthy running system. The longer a filter remains in place, the harder it becomes to get air through it and can lead to symptoms such as:

- A blower motor failure

- Improper metering of the refrigerant

- Poor air quality

- Poor air supply which can lead to an evaporator coil freeze up

The Outdoor Condensing Unit Or Heat Pump

Whether you have a heat pump or AC condenser, this is the unit that contains the compressor. What makes the difference between being a heat pump or an AC condenser is that heat pumps require extra components such as a defrost control board or a reversing valve. They each serve the purpose of supplying air conditioning while only heat pumps can serve as a source of heat through refrigeration. Either one requires sufficient airflow through the coil to achieve satisfactory performance. As seen in the picture, the restriction of airflow will cause excessive high pressure in the summer and quick freeze ups in the winter on heat pumps. Clean coils, sufficient capacitors, and well-functioning contactors keep your outdoor units up to speed.

When mowing the lawn near your outdoor AC condenser or heat pump, it’s a good idea to turn off the air conditioning unit to protect its efficiency and longevity. The condenser can easily suck in grass clippings, dirt, and debris, as seen in this heavily clogged condenser coil above. This buildup can obstruct airflow, strain the system, and lead to costly repairs or reduced performance. Shutting off the AC during mowing prevents these contaminants from being drawn in, ensuring your unit remains cleaner for longer and operates effectively. Even with precautionary practices, the outdoor unit will get dirty eventually so if you need your condenser cleaned professionally, contact us for a thorough cleaning to maximize efficiency and performance. A single yearly cleaning before summer on AC condensers and a twice-yearly cleaning for Heat Pumps is the minimal recommendation for longevity.

A clogged condenser or heat pump coil will trigger symptoms such as:

- Long or short run times (depending on your setup)

- Loss of efficiency/higher energy bills

- Incorrect refrigerant metering

- Poor performance

- Compressor Failure

- Fan motor failure

- Evaporator coil freeze up

Your Breaker Panel or Disconnect Box

A home’s breaker panel distributes electricity to circuits and uses breakers to cut power during overloads or faults, preventing fires and damage.

A home’s breaker panel, also known as an electrical panel or circuit breaker box, distributes electricity from the main power supply to various circuits throughout the house. It houses circuit breakers, which are safety devices designed to protect electrical circuits from overloads or short circuits by automatically cutting off power when a fault is detected. This prevents electrical fires, equipment damage, and other hazards. Tripped breakers should be reset cautiously because a trip indicates a potential issue, such as an overloaded circuit, a short circuit, or a ground fault. Resetting without investigating the cause could mask a serious problem, leading to repeated tripping, damage to wiring or appliances, or fire risks. Before resetting, ensure no devices are malfunctioning or overloaded, and check for visible signs of electrical issues. For appliances like a condensing unit (part of an HVAC system), professional inspection and repair before resetting a tripped breaker are critical. These units involve complex electrical and mechanical components, and a tripped breaker may indicate issues like compressor failure, performance issues, or wiring faults. Attempting to reset without addressing the root cause could damage the unit further, pose safety risks, or lead to costly repairs. Obsidian Air Solutions LLC can diagnose and fix the issue safely, ensuring compliance with electrical codes and preventing hazards.

Abnormal And Obnoxious Noises

If you hear anything other than air moving inside the house and a smooth humming from the outdoor condenser or heat pump, issues are likely afoot.

Consult a professional HVAC technician for diagnosis and repair due to complex components and safety risks.

Banging/Clanging: Loose or broken parts (blower wheel, motor mount) or failing compressor. Moderate to severe.

Screeching/Squealing: Worn belts, bad bearings, or fan blade rubbing. Moderate.

Humming/Buzzing: Electrical issues (faulty capacitor, contactor) or loose parts. Moderate to severe.

Rattling/Vibrating: Loose panels, debris, or unbalanced fan. Mild to moderate.

Hissing/Whistling: Refrigerant leak, duct leaks, or clogged filter/vents. Moderate to severe.

Gurgling/Bubbling: Improperly designed, damaged, or clogged condensate drain. Moderate to severe.

Clicking/Ticking: Normal relay clicks, faulty electrical components, or debris. Mild to moderate.

Thumping/Pulsing: Unbalanced blower, motor issues, or duct vibration. Moderate.

Note: Persistent or loud sounds, especially with performance issues, require immediate professional inspection. Turn off the system for hissing or buzzing and contact Obsidian Air Solutions LLC to prevent damage or hazards.

The 20 Degree Rule And How It's Misconstrued

Many folks have heard of the 20 degree rule as a general reference and it is often misconstrued in the false understanding that your home can only achieve a 20 degree difference in temperature between outdoor and indoor. The ruth is, the 20 degree rule refers to the intake and output temperature difference your central HVAC system can achieve and its roughly 15-20 degrees, not 20 exactly.

This means that on a 100 degree summer day, as long as your home or structure is well insulated, you can achieve a 68 degree indoor temperature if your system is working well. Of course this will run up your power bill and require a higher demand of your equipment though! So, in reality, whether your home is 90+ degrees inside or 75, your output air should be within 15-20 degrees cooler than what it pulls in. Your home's insulation and air leaks, your air filter, and your system's overall performance all participate in this calculation of achievable temperature.