Chapter 2 of this compliance manual addresses the compliance and enforcement process generally and discusses the roles and responsibilities of each of the major parties, the compliance forms, and the process for field verification and/or diagnostic testing. This section highlights compliance enforcement issues for water heating systems.
The design review verifies that the certificate of compliance matches the plans and specifications for the proposed building. The certificate of compliance has a section where special features are listed. The following are water heating features that should be listed in this section of the certificate of compliance:
1. Any system type other than one water heater per dwelling unit
2. Non-NAECA large water heater performance
3. Indirect water heater performance
4. Instantaneous gas water heater performance
5. Distribution system type and controls
6. Solar system
7. Combined hydronic system
If any of these measures are called out on the certificate of compliance, special attention should be given to make sure that identical information is located on the plan set. Highlighting key concerns or adding notes will allow field inspectors to quickly catch any measures that should be installed that made a significant difference in compliance.
During construction, the contractor or the specialty contractors or both complete the necessary sections of the certificate of installation. For water heating, there is only one section to be completed where information about the installed water heating system is entered if complying prescriptively with the installation of a gas instantaneous, gas storage above 55 gallons, or a NEEA Tier-3 rated heat pump water heater. Additional documents will be needed to comply prescriptively for all other options. (See Appendix A)
Inspectors should check that the number and types of water heating systems indicated on the installation certificates match the approved certificate of compliance. The distribution system is also significant and must correspond to plan specifications.
5.11.3.1 Single Family and Multifamily With Individual Dwelling Water Heaters
HERS verification is required for all hot water distribution types that include options for field verification. The first type is alternative designs to conventional distribution systems that include parallel piping, demand recirculation, and automatic and manual on-demand recirculation. The second type is for compact distribution systems earning the expanded credit, which can be used only when verified by field verification. For all of the cases where HERS verification is required, the HERS Rater must verify that the eligibility requirements in RA3.6 for the specific system are met.
In addition, HERS-verified drain water heat recovery is an option for prescriptive compliance and as a compliance credit for the performance approach.
As previously described in this chapter, if a user wishes to comply prescriptively with the Energy Standards and installs a minimally compliant gas storage water heater (55 gallons or less), then either the compact distribution design (expanded credit) or a compliant drain water heat recovery system must be installed, both of which require HERS verification.
5.11.3.2 Multifamily With Central Water Heating Systems
The HERS verification for water heating that applies to central domestic hot water recirculation systems in multifamily buildings is the verification of multiple distribution lines for central recirculation systems, and the verification of drain water heat recovery systems.