Return vents should always remain open. Closing them chokes off the air being pulled back into your HVAC system, causing increased static pressure, higher energy bills, and potential damage to your system's blower motor.
The return vents in your home help equalize the pressure that changes as your HVAC system heats or cools your home. These vents should never be fully closed because closing them off restricts airflow and strains the system.
Yes, mice can easily crawl through vents and ductwork. Because their skulls are highly flexible, a mouse can squeeze through any opening that is just the size of a nickel or a pencil (about 14one-fourth14 to 38three-eighths38 of an inch).
Common Signs Your Furnace May Not Be Venting Properly
HVAC Return Air Requirements: Codes and Best Practices
Square Footage Guidelines: A typical rule of thumb is one return vent for every 600 to 900 square feet of living space. Larger areas, such as homes over 2,000 square feet, generally need multiple return vents.
Problems arise when return air vents are blocked by furniture, rugs, or decorative covers. These vents don't blow air into a room like supply vents. Instead, they pull air back into the HVAC system, which is why they're often overlooked. Over time, blocked return vents restrict airflow and disrupt system balance.
One of the most common mistakes in HVAC duct fabrication is incorrect measurements. Ducts that are too small or too large for the system or the home will lead to airflow restrictions, energy inefficiencies, and increased noise levels.
In general, you can expect your furnace to cycle (on-off) about 3 to 8 times per hour in cold weather. Several factors determine how often the furnace cycles on in winter. The key factor is the outdoor temperature and the heat loss rate of your home.
Here are some symptoms that'll show up when there's not enough return air:
What fails first on a furnace? The most common early failures are the furnace ignitor or flame sensor, as they experience regular wear and tear and are critical to starting the heating cycle.
The Amish control mice through non-chemical, self-sustaining methods, relying on active trapping, natural scent repellents, and structural exclusion. Rather than using commercial poisons, they focus on physical barriers and natural predators to keep rodent populations in check.
Mice have an incredibly sensitive sense of smell and absolutely despise strong, pungent, or spicy aromas. These smells overwhelm their senses and act as natural deterrents.
You might think that spotting one mouse means you only have one mouse. This rarely happens. Mice live in family groups and reproduce quickly. If you see one mouse during the day, it usually means the hidden population has grown large enough that they're competing for food and space.
Should Return Air Vents Be Open Or Closed In Winter? Once again, NEVER close a return air vent. If you have operable cold air SUPPLY vents in your home, you can close upper supply air vents and keep lower return air vents open in the winter to keep your home cozy while allowing your heating system to work efficiently.
How many return vents should a house have? At least one per floor, but often one per major room provides the best performance.
Ideally, a house should have at least one return vent in every habitable room (excluding kitchens and bathrooms), plus one to two large central returns per floor. However, in many homes, a single, centrally located return vent or one per floor is standard.
5 Warning Signs It's Time for Furnace Replacement
The heat exchanger is often considered the most costly part of a furnace to repair or replace. It is a critical component that transfers heat from the combustion process to the air that circulates throughout your home. Over time, heat exchangers can crack due to the constant heating and cooling cycles they undergo.
Furnaces should cycle 3-8 times per hour. Short cycles may indicate oversized units or airflow issues. Long cycles can signal undersized furnaces or insulation problems. Regular maintenance helps ensure proper cycling and performance.
It takes time for your home to warm up and cool down. If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it.
Typically, a furnace should cycle 3 to 8 times per hour, running for about 10 to 15 minutes each time. If it's cycling more frequently (short cycling) or running for 20+ minutes straight regularly, something's not right.
No, 68°F is not generally considered cold for a house in winter. In fact, experts at the U.S. Department of Energy recommend 68°F as the ideal, energy-efficient temperature for the winter months while you are awake.
In HVAC duct design, the two-foot rule is a guideline stating that branch ducts (takeoffs) must be placed at least 24 inches away from any air direction change, transition, or end cap. This spacing allows turbulent air to re-pressurize and stabilize, ensuring consistent airflow to every room.
One of the most surprising places they can hide? Your ductwork. That's right: your heating and ventilation system may be more than just a pathway for warm or cool air; it could also be a cozy travel route (and nesting spot) for mice.