Rinnai Corporation Hydronic Furnace (37AHB) Manual
3
INTRODUCTION:
The optimum in hydronic technology: the updated
Rinnai® multi-position Hydronic Furnaces offer a
unique solution for a wide variety of small and medium
sized residential and light commercial applications.
They are compact and ready to fit in tight spaces
which may include, but not limited to, attics,
basements, closets, crawlspaces, and utility rooms.
The 37AHB units are equipped with an intelligent
microprocessor control that allows for domestic hot
water priority and adapts to available hot water flow for
space heating by automatically regulating the pump
and blower sequence to maximize comfort.
These unique Hydronic Furnaces are designed to
work in combination with our line of Rinnai® tankless
products to deliver a wide variety of heating capacities
that cover the entire residential and light commercial
heating spectrum.
Because our units are designed specifically to the
Rinnai® tankless products, our stated capacities are
fine tuned and are based on the “Hydronic Furnace /
Tankless Water Heater” match set and
NOT
a given
water flow rate.
CODES AND STANDARDS:
It is the responsibility of the installer to follow all
national codes, standards and local ordinances, in
addition to instructions laid out in this manual. The
installation must comply with regulations of the local
building, heating, plumbing, and other codes. Where
local codes are not applicable, the installation must
comply with the national codes and any and all
authorities having jurisdiction.
Overview of the Rinnai Hydronic Furnace (RHF)
The following is a suggested list of codes and
standards for the United States and Canada:
General Installation
Installation of Air Conditioning and Ventilating Systems
NFPA 91 (latest edition)
Duct Systems
Sheet Metal and Air Conditioning Contractors National
Association (SMACNA)
American Society of Heating, Refrigeration, and Air
Conditioning Engineers (ASHRAE)
2001 Fundamentals Handbook Chapter 34 or 2000
HVAC Systems and Equipment Handbook Chapters 9
and 16
US and CANADA: Air Conditioning Contractors
Association (ACCA) Manual D
Acoustical Lining and Fibrous Glass Duct
US and CANADA: current edition of SMACNA; NFPA
90B as tested by UL Standard 181 for Class I Rigid Air
Ducts
Electrical Connections
US: National Electrical Code (NEC) ANSI/NFPA 70
(latest edition)
CANADA: Canadian Electrical Code CSA C22.1
(latest edition)
Plumbing Systems:
US and CANADA: ICC International Plumbing Code
(IPC); Uniform Mechanical Code (UMC); Uniform
Plumbing Code (UPC)
Model Number Nomenclature
37AH B 045 08 K A 5
Multi-position
5 = Yes
2 = No
Engineering Digit
Denotes minor change
(not present in sales or service
literature)
Voltage Code (V-Ph-HZ)
K = 115 - 1 - 60
L = 240 - 1 - 50 (export models)
Model
37AH - Multi-Speed Hydronic Furnace
Series
A - Unit with PSC Motor
B - Unit with ECM Technology
Nominal Heating
Capacity (BTU/h)
045 = 45,000
060 = 60,000
075 = 75,000
090 = 90,000
Cooling / Heating Air Flow Range (CFM)
08 = 800 (650-800)
12 = 1200 (650-1200)
14 = 1400 (1000-1600)
16 = 1600 (1200-1750)
