© Copyright CalCERTS, Inc. 2019
Code Cycle: 2016 Standards
Reference: 2016 CalCERTS Alterations Training Manual Chapter 6
Mini-split, Multi-split, Variable Refrigerant Flow (VRF), or Variable Refrigerant Volume (VRV) space conditioning systems, can be configured to allow a single outdoor condensing unit to simultaneously drive multiple indoor evaporator coils/indoor units serving either ducted and/or non-ducted zones. HERS Refrigerant Charge Field Verification and Diagnostic Testing (FV/DT) of ducted or ductless multi-split space conditioning systems requires testing methods that conform to that type of equipment.
The following protocol shall be applied to FV/DT and reporting of the results in the HERS Provider Registry.
Refrigerant Charge – Refrigerant charge verification must be performed by means of Rater Observation of the Installer’s Weigh-in Charging Procedure as per RA3.2.3:
When the Standards indicate this procedure is required, or is an option for compliance, the HERS Rater shall coordinate with the HVAC Installer to observe the weigh-in charging procedure.
RA220.127.116.11: HERS Rater shall observe and confirm:
- The system is evacuated to 500 microns or less and, when isolated, rises no more than 300 microns over five minutes.
- The lineset correction is calculated based on the length and diameter of the lineset, including the liquid line filter drier if required per outdoor condensing unit manufacturer instructions.
- The indoor coil correction to refrigerant weight is used if it is supplied by the manufacturer.
- The installer adds or removes the amount of charge calculated for the lineset correction or installs the total charge based on lineset, indoor coil, and standard label charge.
Note: When the weigh-in method is used, group sampling of this energy feature is not allowed.
150.1(c)7A - Refrigerant Charge
Refrigerant Charge. When refrigerant charge verification or fault indicator display is shown as
required by TABLE 150.1-A or Table 150.1-B, the system shall comply with either 150.1(c)7Ai or 150.1(c)7Aii:
i. air-cooled air conditioners and air-source heat pumps, including but not limited to ducted split
systems, ducted packaged systems, small duct high velocity systems, and mini-split systems, shall
comply with subsections a, b and c, unless the system is of a type that cannot be verified using the
a. Have measurement access holes (MAH) installed according to the specifications in the
Reference Residential Appendix Section RA18.104.22.168; and
b. System airflow rate in accordance with subsection I or II below, shall be confirmed through
field verification and diagnostic testing in accordance with all applicable procedures specified
in Reference Residential Appendix Section RA3.3 or an approved alternative procedure as
specified by RA1; and
c. The installer shall charge the system according to manufacturer’s specifications. Refrigerant
charge shall be verified according to one of the following options, as applicable:
150.1(c)7Aii - Air-cooled air conditioners and air-source heat pumps, including but not limited to ducted split systems, ducted packaged systems, small duct high velocity systems and mini-split systems, which
are of a type that cannot comply with the requirements of 150.1(c)7Ai shall comply with subsections a and b, as applicable.
a. The installer shall confirm the refrigerant charge using the weigh-in charging procedure
specified in Reference Residential Appendix Section RA22.214.171.124, as verified by a HERS Rater
according to the procedures specified in Reference Residential Appendix Section RA126.96.36.199;
b. Systems that utilize forced air ducts shall comply with the minimum system airflow rate
requirement in Section 150.1(c)7Aib provided the system is of a type that can be verified
using the procedures in RA3.3 or an approved alternative procedure in RA1.
Refrigerant Charge Airflow
Ducted zones of VRF systems shall be exempt from the minimum airflow requirements.
The exception to airflow my be claimed by selecting "No" on the CF2R-MCH-25 in field A12.
Note: This does not apply to single-zone systems which shall use standard verification protocols.