Manual S HVAC Equipment Selection – Just the Right Size

When it comes to choosing adequate equipment to provide central heating and air conditioning to a home, it’s of utmost importance to have pinpoint accuracy when calculating the necessary load. If the calculations are too conservative, the homeowner may be stuck with a system that can’t handle the needs of the home. If the calculations are too generous, the homeowner may be stuck with a utilities bill that reflects how much unnecessary energy this too-large system is draining. Either way, the homeowner loses money, and the contractor loses face. That’s why investing in Manual S HVAC equipment selection is so important.

In the world of heating, ventilation, and air conditioning (HVAC), the load of a central heating and air conditioning system refers to the amount of heating or air conditioning a home needs. These needs may be exacerbated by any factors that cause the home not to retain energy efficiently; for example, if the home is not sealed, then there is a lot of potential for air to leak from the home, making it necessary for the HVAC system to work harder to heat or cool the home. That’s where Manual S HVAC equipment selection can be very helpful in making sure that you choose a system that can handle the load of a home.

ACCA Manual S Equipment Selection using OEM info - not AHRI

ACCA Manual S HVAC Equipment Selection requires manufacturer’s OEM data

Manual S is a manual compiled by the Air Conditioning Contractors of America (ACCA) to outline the best practices for selecting and sizing HVAC equipment for a home. As the nation’s largest HVAC contractor organization, the ACCA has hundreds of experts at its disposal, and it has compiled this manual as a guide for those who want to draw from these experts’ wisdom and experience. The real-world experience of these experts is what makes Manual S HVAC equipment selection so accurate and so easy to use.

When you use Manual S HVAC equipment selection, you can rest assured that the system you choose will be the perfect size for the home in question. When a homeowner sees that the HVAC contractor is using Manual S to choose the equipment for their home, he can immediately rest assured that this new HVAC system will be able to handle anything that their home can throw at it. It’s not only the perfect way to ensure that no energy is wasted, but also a great way to give both the homeowner and the contractor some peace of mind.


Be sure to check out Savoy Engineering Group’s post on the ACCA Manual S residential HVAC sizing calculation. It will help you understand how critical OEM data is.