Instructions

1. Select whether you are sizing equipment for a New Home or an Existing Home.
2. (OPTIONAL) Fill in user's name, email address, and select type of organization from pull-down menu (Home manufacturer, HVAC installer, Home installer, Home Retailer, Equipment supplier, Utility, Homeowner, Other).
3. (OPTIONAL) Fill in the inputs: Serial No., Homeowner Name, MH Plant Name, Final Site Address, City, and Zip.
4. Select all required parameters (marked in red*). Start with Design State – the list of cities will update accordingly. Pick your Design City from the dropdown – select the nearest city to your site or one with the most similar climate and elevation.
5. Choose the Home Type (Single, Double, or Triple Wide) and enter the Floor Area (ft²). Then choose the Code/Program – HUD, ENERGY STAR v3/Efficient New Homes v1, or ENERGY STAR v3/Efficient New Homes v1 Improved Envelope. Users with ENERGY STAR v2 homes may use the tool to check results by comparing the Uo value displayed in the Design Conditions section with the Uo value of their home. If the values are similar, the results may be applicable.
6. New Home ONLY: Select the Installed Indoor Unit: choose the indoor unit model installed in the home. The tool will use this input to display only compatible matched outdoor equipment.
7. Click RUN.
8. RESULTS:
   • New Home: The results will display the design conditions and type, make and model of suitable equipment. At this point you can print the results, elect to run another home, or click on a model section to obtain detailed equipment performance data at design conditions for that equipment model.
   • Existing Home: Results will display design conditions and nominal equipment size. You can print results or run another home.

Exclusions and Notes

• The tool should not replace any sizing or equipment guidance provided by the manufacturer, which should always take precedence.
• Homes in CZ-1 with floor ducts should consider reducing equipment size by one half ton. Homes in CZ-2 and CZ-3 with attic ducts should consider increasing equipment size by one half ton.
• New Home:
  • In cases where the summer design temperature results in negligible or no cooling load, heat pump sizing may be based on heating design conditions, with cooling capacity provided only to meet minimum ventilation or occupant comfort needs. Users should note that this approach may result in cooling equipment that is oversized.
  • In cases where latent cooling load is a significant portion of the total cooling load, equipment may be oversized to ensure adequate moisture removal.
  • For single-speed air conditioners, Manual S (2023) allows total cooling capacity between 90% and 120% of cooling load for design cooling loads ≤ 24,000 Btuh, or 115% of cooling load for design cooling loads ≥ 24,000 Btuh. Manual S also requires minimum sensible capacity of 90% of the sensible load and requires latent capacity to meet or exceed 100% of the calculated latent load.
  • If no equipment option is displayed, none of the equipment in the tool's database meets the Manual S sizing limits for the given Manual J design loads. Please consider an alternative design methodology.
  • The tool does not imply approval of oversized or undersized heating equipment. A warning will appear if the selected indoor unit is below 100% or above 200% of the estimated heating load.
• Existing Home:
  • Calculations are based on thermal provisions of the Manufactured Home Construction and Safety Standards (24 CFR §3280, Subpart F) applicable to homes built after 1994, or the ENERGY STAR program version selected. Results do not account for post-construction modifications to the home, effects of age, insulation degradation, or other conditions that may affect the home's thermal performance.

About This Tool

This tool is for use with manufactured homes built to the HUD Code (thermal provisions of the Manufactured Housing Construction and Safety Standards, Subpart F, Section §3280), including manufactured homes certified as ENERGY STAR® and DOE Efficient New Homes.

It provides a simple look-up procedure to assist equipment specifiers, HVAC contractors, home installers, retailers, manufacturers, and electric utility staff. For new manufactured homes, it guides in selection of single speed heat pumps and air conditioners. For existing homes, it determines design conditions and nominal equipment size. The guidelines provide a simple but accurate procedure that reduces oversizing and its associated problems.

If you are a HUD Code home or cooling equipment manufacturer and want the cooling equipment you use or manufacture to be included in the tool, please contact Systems Building Research Alliance (SBRA) at info@research-alliance.org.

Detailed information about how this tool was created and its underlying technical assumptions may be found in the Manufactured Home Cooling Equipment Sizing and Selection Tool Technical Report.

Systems Building Research Alliance is a non-profit organization with the mission of developing new technologies to enhance the value, quality, and performance of the nation's factory-built homes, both manufactured and modular. The Florida Solar Energy Center performed the thermal load calculations for this tool with EnergyGauge USA™, an Air Conditioning Contractors of America (ACCA)-endorsed software version of ACCA Manual J, Load Calculation for Residential Winter and Summer Air Conditioning, Eight Edition. CodedEnergy developed the Manual S-based equipment selection module.

Disclaimer

The results of this tool are intended as a guide for equipment selection and should not be used in lieu of a specific design provided by the home manufacturer. This information is not a substitute for proper evaluation and judgment by an equipment specifier. The cooling and heating load estimates are based on typical home configurations and assumed design conditions. Actual sizing requirements may differ from the values provided. SBRA, its subcontractors, and the sponsors of this work assume no liability for damages resulting from the use of this tool or from any errors in equipment sizing, selection, or installation.

Privacy Policy

The Manufactured Home Cooling Equipment Sizing and Selection Tool stores data input by users to track usage and identify needed improvements and enhancements to the tool. Individual data will not be shared outside of SBRA except in the aggregate. No personally identifiable information (User's name or email address, home's serial number, homeowner name, MH plant name, final site address) will be shared outside of SBRA except with written permission of the user.