Combustion Air Supply - American Water Heater 240HX3 Installation Manual And Owner's Manual

On-demand water heater

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Table Of Contents

Table of Contents

This gas water heater requires an adequate source of clean air for combustion and

ventilation. Without sufficient air, your water heater may not operate properly and

may emit excessive and abnormal amounts of carbon monoxide which may result in

WARNING

carbon monoxide poisoning or death.

The guidelines in this section apply to installations within the United States. All U.S.

NOTICE

installations must conform to the National Fuel Gas Code, ANSI Z223.1/NFPA 54 (cur-

rent edition) and local codes.

Before installing the water heater, you must determine the amount of air needed to supply this water heater and

any other gas appliances in the same area and provide adequate air for combustion and ventilation. Consult a

qualified person if you're unsure of the proper way to supply air to your water heater.

Check for Chemicals:

Air for combustion and ventilation must be clean and free of corrosive chemicals. If corrosive chemicals, such as

sulfur, flourine, or chlorine are present, the water heater must be direct vented. Failure due to these corrosive

chemicals is not covered by the warranty.

WARNING!

In all cases, ensure that corrosive chemicals are not present at the air intake. Presence of such chemicals at the

air intake could result in death, personal injury, or property damage. Examples of locations that require outside air

due to chemicals include:

•

Beauty salons

•

Photo processing labs

•

Indoor pools

•

Laundry, hobby, or craft rooms

•

Chemical storage areas

•

Restaurants

Products such as aerosol sprays, detergents, bleaches, cleaning solvents, gasoline, air fresheners, paint and varnish

removers, and refrigerants should not be stored or used near the water heater.

Does your installation space have sufficient combustion air?

Ventilation with outside air is recommended for all installations. Even if the water heater is installed in a large,

open room inside the house, outdoor air is usually needed because modern homes are very tightly sealed and

often do not supply enough air to the water heater. However, when installed in a large indoor space, it may be

possible to provide enough air without outside ventilation. If you are unsure if your installation location has

enough ventilation, contact your local gas utility company or code officials for a safety inspection or direct vent

the water heater

The following instructions will help determine if it may be possible to install the water heater without outside

ventilation.

Calculate total BTU/h rating of all appliances.

To calculate the combustion air and ventilation required, add up the total BTU/h ratings of all gas burning appli-

ances (e.g., water heaters, furnaces, clothes dryers) in the same area. Do not include appliances that are direct

vented. Refer to the following example.