GEO76-800
July, 2014
THE TECHNICAL TIMES Geothermal Standards: What do they mean?
AHRI, ISO, ETL, CSA, UL, CFR, DOE, Energy Star,
……., and on and on. It seems like the parade of
acronyms is never ending when first exposed to
geothermal heat pump specifications and
documentation. The purpose of this paper is to clarify
what each stands for, why it’s important, and to
remove any misconceptions about when and why
each one is or isn’t required.
including capacities, EER, COP, etc. The significance
of this will be discussed in more detail later.
The test standards differ based on the type of water
source heat pump:
 Water to Air – ANSI/AHRI/ASHRAE ISO
13256-1
 Water to Water – ANSI/AHRI/ASHRAE ISO
13256-2
United States Department of Energy (DOE)
Let’s start with the basics: what defines a heat pump?
In the United States, it is defined as any water-source
heat pump. The minimum efficiency required to be
sold in the US is defined by the Energy Efficiency
Program for Certain Commercial and Industrial
Equipment (10 CFR 431, Subpart F)1, which is
enforced by the DOE. This document also defines the
acceptable testing standards used to determine the
efficiency and output ratings of water source heat
pumps.
Program Requirements:
 ANSI/AHRI/ASHRAE ISO Performance
Ratings Test
o Ratings must meet or exceed current
10 CFR 431 efficiency requirements
 Manufacturer submission of data to DOE
International Organization for Standardization
(ISO)
There are two ISO standards that describe all aspects
of the testing procedure, from the modifications
allowed to the units being tested to the appropriate
markings to apply to the unit. Also included are the
requirements for publishing unit performance data for
rating points and expanded performance tables or
“application ratings”. The published performance data
must match the test data obtained during testing,
Third Party Certification
Several companies, such as Air-Conditioning,
Heating, & Refrigeration Institute (AHRI), Canadian
Standards Association (CSA), Intertek (ETL),
Underwriter’s Laboratories (UL), provide independent
testing and verification services to manufacturers.
These companies review all aspects of product design
and test products to ensure that they comply with the
applicable standards. The company will then provide
a manufacturer with a document stating the model
names and sizes, along with which standards the
product complies with. The company seal will then
appear on the product serial plate and literature.
Energy Star Certification
Energy Star2 is a federal energy efficiency and
consumer protection program administered and
maintained by the US Environmental Protection
Agency (EPA) and enforced by the Department of
Energy. The requirements of the program are
designed to promote highly efficient, robust, high
quality products through minimum efficiency levels,
warranty terms, product design, third party product
certification, and market education.
Compliance with the program is maintained by annual
audit review and testing of a specified percentage of a
manufacturer’s product offering.
Energy Star certification is required for a homeowner
to qualify for the 30% federal tax credit for geothermal
heat pump property3.
Program Requirements:
 ANSI/AHRI/ASHRAE ISO Performance
Ratings Test by Third Party Certification
Agency
o Initial Testing
o Ratings must meet or exceed current
Energy Star efficiency requirements
o Annual Audit Testing
 Third Party Certification Agency submission of
data to EPA/DOE
 Residential Product (not 3 phase voltage, etc.)
 Minimum 5 years parts and labor warranty on
major refrigeration components, 2 year parts
and labor warranty on all other components
Air-Conditioning, Heating, & Refrigeration Institute
(AHRI) Certification
AHRI has a third party performance verification
program for geothermal and water source heat
pumps4. This program provides a third party
confirmation of a manufacturer’s published standard
rating points, in accordance with the
ANSI/ARI/ASHRAE ISO standard test procedure for
the product.
Compliance with the program is maintained by annual
audit testing of a specified percentage of a
manufacturer’s product offering, the results of which
are compared to the manufacturer’s published rating
points. The results of the audit tests must be no less
than 95% of the published ratings or the model in
question must be re-rated or discontinued.
Program Requirements:
 ANSI/AHRI/ASHRAE ISO Performance
Ratings Test by AHRI
o Initial Testing
o Annual Audit Testing
 Third Party Certification Agency submission of
data to AHRI
 Test results not less than 95% of published
ratings
Summary
Neither Energy Star nor AHRI certification is required
to sell heat pumps in the US. The only true
requirement is a manufacturer’s certification that the
product meets the minimum performance
requirements set out in 10 CFR 431.
It is important to note the difference in purpose
between the Energy Star and AHRI programs:

The federal Energy Star program sets
minimum efficiency requirements, along with
certain other physical, warranty, and testing
requirements for a product to carry the Energy
Star logo and qualify for the federal tax credit.

The third party AHRI program is a
performance verification program, which
means that AHRI certifies that the ratings
being published by a manufacturer are being
met. There are no efficiency requirements set
by this program; it is simply a confirmation of
a manufacturer’s published performance data.
It is possible and very likely that a residential heat
pump will carry both the Energy Star and AHRI
Certified marks. It is just as likely that a heat pump
will only carry the AHRI Certified mark, as it may not
be efficient enough or meet other requirements
needed to qualify for Energy Star certification.
References
https://www.federalregister.gov/selectcitation/2014/05/15/10-CFR-431=
2
http://www.energystar.gov/certifiedproducts/detail/499/partners
3
http://www.irs.gov/pub/irs-irbs/irb09-19.pdf
4
http://www.ahrinet.org/site/833/Certification/AHRICertification-Programs/Geothermal-Water-SourceHeat-Pumps
1
Commercial Products Group  Modine Manufacturing Company  1500 DeKoven Avenue  Racine, WI USA 53403-2552
Phone: 1.877.679.4436 (4GEO)  www.modinehvac.com
© Modine Manufacturing Company 2014
GEO76-800