Energy Code Ace - Overview

4.1 Overview

4.1.1 Introduction and Organization

This chapter addresses the requirements for heating, ventilating, and air-conditioning (HVAC) systems for newly constructed single-family residential buildings include single family residences, duplexes, townhouses, and triplexes. The requirements are a source of information for the general public, mechanical system designers and installers, energy consultants, Home Energy Rating System (HERS) Raters, and enforcement agency personnel.

Each section in this chapter outlines the mandatory measures and, when applicable, the prescriptive and performance or compliance options as they pertain to residential HVAC systems. If the overall home design does not achieve the minimum prescriptive requirements, the designer can consider using the HVAC performance compliance option that allows for making up the deficiencies. See Chapter 1.6 of the Residential Compliance Manual for a more detailed discussion of the compliance process and options.

Each section of this chapter includes mandatory measures, prescriptive requirements, and performance or compliance options. The chapter is organized under the following sections:

Section 4.2 – Heating Equipment.
Section 4.3 – Cooling Equipment.
Section 4.4 – Air Distribution, System Ducts, Plenums and Fans .
Section 4.5 – Controls
Section 4.6 – Indoor Air Quality and Mechanical Ventilation.
Section 4.7 – Alternative Systems.
Section 4.8 – Refrigerant Charge.
Section 4.9 – Compliance and Enforcement.

Chapter 9 of the Residential Compliance Manual covers the heating and cooling requirements for additions to existing dwellings and for alterations to existing heating and cooling systems.

Chapter 10 of the Residential Compliance Manual covers the electric ready requirements (new under the 2022 Energy Code) including electric readiness for gas and propane furnaces and domestic hot water heaters.

4.1.2 What’s New for the 2022 Energy Code

The following is an overview of the new HVAC measures for the 2022 Building Energy Efficiency Standards (Energy Code), including new compliance options that provide greater flexibility in complying with the Energy Code when using the performance method.

4.1.2.1 Mandatory Features and Devices - §150.0

Portions of duct systems located in conditioned space and entire duct systems located in conditioned space can be uninsulated if specific conditions are met, as explained in Section 4.4.1 (§150.0(m)1B).
Updated ventilation requirements based on applicable sections of 2019 ASHRAE 62.2 and added clarification language (§150.0(o)).
Updated local exhaust requirements for kitchen range hoods which includes capture efficiency ratings (§150.0(o)1G).
Filter racks or grilles must use a gasket or sealing to prevent air from bypassing the filter (§150.0(m)12Bv).

4.1.2.2 Prescriptive and Performance Compliance Approaches − §150.1

Space heating systems used in prescriptive compliance must be a heat pump for climate zones 3, 4, 13, and 14 (§150.1(c)6).
Variable Capacity Heat Pump Compliance Option that was approved in November 2019 is incorporated into the 2022 Energy Code (§150.1(b)3Bii).

4.1.3 California Appliance Standards and Equipment Certification

§110.0 and §110.1

Most heating and cooling equipment installed in new California homes is regulated by the National Appliance Efficiency Conservation Act (NAECA) and/or the California Appliance Efficiency Regulations (Title 20). Both the federal and state appliance standards apply to the manufacturing and sale of new equipment, whether for newly constructed buildings, additions, or alterations (replacements, or repairs). The Appliance Efficiency Regulations are enforced at the point of sale (except central split-system air conditioners and central single package air conditioners, see Table 4-6), while the Energy Code explained in this compliance manual is enforced by local enforcement agencies.

The manufacturer must certify that the equipment complies with the current Appliance Efficiency Regulations at the time of manufacture. Appliances covered by the Appliance Efficiency Regulations include:

Room air conditioners
Room air-conditioning heat pumps
Central air conditioners with a cooling capacity of less than 135,000 British thermal units per hour (Btu/hr)
Central air conditioning heat pumps
Gas-fired central furnaces
Gas-fired boilers
Gas-fired furnaces
Gas-fired floor furnaces
Gas-fired room heaters
Gas-fired duct furnaces
Gas-fired unit heaters

The Appliance Efficiency Regulations do not require certification for:

Electric resistance space heaters.
Oil-fired wall furnaces, floor furnaces, and room heaters. (Some are voluntarily listed with certified gas-fired furnaces.)

Equipment that does not meet the federal appliance efficiency standards may not be sold in California. Any equipment covered by the Appliance Efficiency Regulations and sold in California must have the date of manufacture permanently displayed in an accessible place on that equipment. This date is frequently included as part of the serial number.

Generally, equipment manufactured before the effective date of a new standard may be sold and installed in California indefinitely as long as the performance approach demonstrates energy compliance of the building using the lower efficiency of the relevant appliances. An exception is central split-system air conditioners and central single package air conditioners installed in California. The U.S. Department of Energy (DOE) requires compliance with the minimum efficiencies specified in Table 4-6 at the time of installation.

The compliance and enforcement processes should ensure that all installed HVAC equipment regulated by the Appliance Efficiency Regulations is certified by the California Energy Commission.

4.1.3.1 Plan Review (Compliance)

During the plan review, the builder is responsible for demonstrating compliance with the Appliance Efficiency Regulations by providing the efficiency of the HVAC equipment that is to be installed. Typically, the builder does not identify the exact make or model at this point of the process. The plans examiner is responsible for verifying that the specified equipment efficiency complies with the Appliance Efficiency Regulations.

4.1.3.2 Field Inspection (Enforcement)

It is the field inspector’s responsibility to visually verify that the product information on the installed HVAC equipment matches the efficiency approved by the plans examiner. To simplify the inspection, the field inspector may reference the CF2R-MCH-01-H submitted by the builder/installing contractor.