Rinnai 37AHA04508KA5 User Manual

37AHA SERIES
HYDRONIC AIR HANDLER
SIZES 045 THRU 090
Installation, Operation, and Maintenance Manual
Quality Assurance
This product is manufactured in a
facility registered by UL to ISO 9001.
File No. A6887.
UL recognized
component
Consumer Safety Information................................ 2
Overview of the Rinnai Hydronic Air Handler........ 3
Model Number Nomenclature ............................... 3
Physical Data......................................................... 4
Receiving & Checking Equipment......................... 5
Installation
Clearances .................................................... 5
Locating and Mounting............................... 6-9
Plumbing................................................. 10-13
Electrical Connections............................ 14-16
Dip Switch Options...................................... 17
Thermostat Installation........................... 17-18
Start-Up Procedure ..................................... 19
Troubleshooting...................................... 20-23
Sequence of Operation ..................................24-26
Maintenance.................................................. 26, 27
Selection Guide ............................................. 27, 28
Specifications ...................................................... 29
Air Delivery Performance .................................... 30
Accessories ......................................................... 31
Hydronic Air Handler Output .......................... 32-34
Wiring Diagrams............................................. 35-37
Parts List......................................................... 38-39
Limited Warranty ............................................ 40-41
2100-500
To register your hydronic air handler or tankless water heater,
please visit www.rinnairegistration.com
.

Rinnai 37AHA04508KA5 Specifications

General

Model Number	37AHA04508KA5
Type	Tankless Water Heater
Fuel Type	Natural Gas
Energy Factor	0.82
Minimum BTU Input	15, 000 BTU/hr

Summary

Consumer Safety Information

Safety Definitions

Defines safety alert symbols like DANGER, WARNING, CAUTION, and NOTICE.

Safety Considerations

Outlines essential precautions for safe installation and operation of the unit.

Receiving and Checking Equipment

Unit Identification

Shipment Inspection

Installation

Locating and Mounting

Guidance on selecting a location and physically mounting the unit.

Unit Configurations and Orientation

Ductwork and Filter Setup

Plumbing and System Purging

Guidelines for water supply, return, and system purging procedures.

Electrical Connections and Wiring

Procedures for making electrical connections and understanding wiring diagrams.

Control System Configuration

Start-Up and Troubleshooting

Procedures for initial start-up and diagnosing operational issues.

Sequence of Operation

Heating Mode Operation

Selection Guide

Sizing and Selection Procedure

Steps for determining the correct unit size based on heating/cooling loads.