An AC Unit
January 16, 2024

Choosing the Right AC Size for Your Mobile Home

With their distinct structural design and insulation levels, mobile homes present unique challenges in maintaining a comfortable indoor climate. Unlike traditional homes, mobile homes’ compact spaces require careful consideration of air conditioning needs. 

An oversized unit can lead to unnecessary energy consumption and humidity issues, while an undersized one struggles to keep up, reducing lifespan and efficiency. Considering all of this, we wrote this guide to help you find the ideal air conditioner for your mobile home, ensuring a cool, comfortable, and cost-effective summer.

Understanding Air Conditioner Sizing

Air conditioner sizing is critical in ensuring your mobile home’s climate control is efficient and effective. The size of an air conditioner is typically measured in British Thermal Units (BTU), a unit of heat that represents the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit. In the context of air conditioners, BTU measures the unit’s capacity to remove heat from your home.

A unit with a higher BTU rating has a greater cooling capacity, ideal for larger spaces, but can be overkill for smaller areas, leading to short cycling and increased wear. Conversely, an air conditioner with a BTU rating too low for your space will run continuously, struggling to reach the desired temperature, leading to increased energy bills and reduced unit lifespan.

Correctly sizing an AC unit for your mobile home is essential for optimal efficiency and comfort. It involves considering not just the square footage of your space but also factors like ceiling height, window size, and insulation quality. An appropriately sized air conditioner will maintain a consistent temperature, reduce humidity levels, and operate efficiently, prolonging its lifespan and saving energy costs. The following sections will delve into determining the right air conditioner size for your specific mobile home needs, ensuring a comfortable and cost-effective living environment.

Factors Influencing AC Size for Mobile Homes

Selecting the right-sized air conditioner for your mobile home involves considering several key factors:

Location and Climate

The geographical location of your mobile home plays a significant role in determining the appropriate AC size. Homes in hotter, more humid climates, such as the Southern United States, will require air conditioners with higher BTU ratings than those in cooler regions. For instance, a mobile home in Florida might need a more powerful unit than a similar-sized home in Maine due to the difference in outdoor temperatures and humidity levels.

Mobile Home Size and Layout

The size and layout of your mobile home are crucial in deciding the AC capacity. Take, for example, a 14×70 mobile home. This common size, measuring approximately 980 square feet, typically requires an air conditioner in the range of 18,000 to 21,000 BTUs under normal conditions. However, this can vary based on the layout, such as the number and size of rooms, windows, and doors, which can affect air circulation and cooling efficiency.

Insulation and Age of the Mobile Home

Insulation quality significantly impacts how well your mobile home retains cool air. Older mobile homes with less effective insulation and more air leakage may require a larger AC unit to maintain a comfortable temperature. Conversely, newer models with better insulation and sealed windows can be efficiently cooled with a smaller unit.

Existing HVAC Infrastructure

Your mobile home’s current heating, ventilation, and air conditioning (HVAC) infrastructure also influences AC size selection. If your home already has ductwork, the size and layout of these ducts will partially dictate the size of the AC unit you can install. Homes without ductwork offer more flexibility but may require additional unit placement and air distribution considerations.

Standard Calculation for Mobile Home AC Sizing

Calculating the right AC size for your mobile home involves a few straightforward steps:

  • Calculate the Square Footage: Measure the length and width of each room in your mobile home and multiply them to get the area. Add up the areas of all rooms to get the total square footage.
  • Consider the Basic BTU Requirement: Generally, you need about 20 BTU per square foot of living space. For example, a 980 square foot mobile home would start at 20 BTU x 980 sq ft = 19,600 BTU.
  • Adjust for High Ceilings: If your mobile home has ceilings higher than 8 feet, increase the BTU requirement by 10% for each additional foot.
  • Factor in Sun Exposure: If your home receives a lot of direct sunlight, increase the BTU capacity by 10%. Conversely, if it’s heavily shaded, reduce the capacity by 10%.
  • Add for Additional Occupants: If more than two people regularly occupy the home, add 600 BTU for each additional person.
  • Consider Kitchen Heat: If the AC unit will cool a kitchen, add 4,000 BTU to the total requirement.

Using this calculation method, you can estimate the appropriate AC size for your specific mobile home.

Specific Guidelines for Various Mobile Home Sizes

What Size Air Conditioner for a 14×70 Mobile Home

The starting point for a standard 14×70 mobile home, which is approximately 980 square feet, would be around 19,600 BTU (using the 20 BTU per square foot guideline). Considering factors like sun exposure, number of occupants, and kitchen heat, the ideal size may range from 18,000 to 21,000 BTU.

Guidelines for Smaller and Larger Mobile Homes

  • For smaller mobile homes (under 800 sq ft): A unit between 12,000 and 18,000 BTU is typically sufficient.
  • For larger mobile homes (over 1000 sq ft): The requirement may exceed 21,000 BTU, especially if additional factors like high ceilings or extra occupants exist.

Remember, these are general guidelines, and adjusting for the specific conditions and layout of your mobile home is essential.

Additional Considerations

Energy Efficiency

Selecting an energy-efficient air conditioner is crucial for reducing long-term costs and environmental impact. Look for models with ratings of high Energy Efficiency Ratio (EER) or Seasonal Energy Efficiency Ratio (SEER). While potentially more expensive upfront, these units consume less energy and can significantly lower your electricity bills over time. Additionally, energy-efficient models often qualify for tax credits or utility rebates, providing further financial incentives.

Installation and Maintenance

Proper installation and regular maintenance are key to the longevity and efficiency of your air conditioner. Incorrect installation can lead to reduced efficiency, increased wear and tear, and even system failures. Hiring a professional HVAC technician for installation is advisable to ensure optimal performance. Regular maintenance, such as cleaning or replacing filters, checking refrigerant levels, and inspecting electrical components, is essential to keep your AC running smoothly and efficiently.

Alternative Cooling Solutions

Besides traditional AC units, consider alternative cooling solutions like window units or heat pumps. Window units are a more affordable, easy-to-install option for smaller spaces but may not be as efficient for cooling large areas. Heat pumps, while more expensive initially, offer both heating and cooling capabilities and are highly energy-efficient. However, they may not be as effective in extremely hot climates.

Final Thoughts on AC Sizing for Mobile Homes

Selecting the right air conditioner for your mobile home balances size, efficiency, and practicality. Consider your home’s size, layout, insulation, and climate when choosing an AC unit. Double wide mobile homes, for example, generally require a larger unit than single wide models. Energy efficiency should be a priority for cost savings and environmental responsibility. 

Professional installation and regular maintenance are crucial for optimal performance. Finally, explore alternative cooling solutions if they better suit your needs. Considering all these factors, you can make an informed decision ensuring comfort and efficiency in your mobile home.