!WARNING:
Products of combustion must not be allowed to enter the return air ductwork or the circulating air supply. Failure to prevent products of combustion from being circulated into the living space can create potentially hazardous con- ditions including carbon monoxide poisoning that could result in per- sonal injury or death.
All return ductwork must be ad- equately sealed, all joints must be taped, and the ductwork must be secured to the furnace with sheet metal screws. When return air is provided through the bottom of the furnace, the joint between the furnace and the re- turn air plenum must be sealed.
The floor or platform on which the furnace is mounted must provide sound physical support of the furnace with no gaps, cracks, or sagging be- tween the furnace and the floor or platform.
Return air and circulating air ductwork must not be connected to any other heat producing device such as a fire- place insert, stove, etc.
Return Air
The return air ductwork may be connected to any or all of the following: left side return, right side return, or bottom return. Tables 1 and 2 show the airflow data for each furnace model.
Where maximum airflow is 1800 CFM or more two openings must be used.
VENTING AND COMBUSTION AIR REQUIREMENTS
NORDYNE condensing furnaces may be in- stalled with outdoor combustion air piped di- rectly to the furnace, or without such special piping. Codes refer to the former as "direct vent" or "two pipe" installation. Installation with air taken from around the furnace is sometimes referred to as "one pipe" installation - i.e. only the vent (exhaust) pipe is provided.
An important consideration in selecting one or two pipe installation is the quality of the combus- tion air. Indoor air is sometimes contaminated with various household chemicals which can cause severe corrosion in the furnace combus- tion system. Some common sources of these chemicals are detergents, bleaches, aerosol sprays, and cleaning solvents. Unless indoor air is known to be free of these materials, two pipe installation is recommended.
Provisions must be made for adequate supply of air for combustion and ventilation. For United States installations, the adequacy of air provi- sions can be determined by consulting the cur- rent version of the National Fuel Gas Code (ANSI
NOTE: If the furnace is operated without ad- equate air for combustion and ventilation, it may not perform properly. Furnace components may be strained by high temperature and could fail prematurely.
!WARNING:
Furnace installation using methods other than those described in the fol- lowing sections must comply with the National Fuel Gas Code and all appli- cable local codes to provide sufficient combustion air for the furnace.
G6RC/G6RD | Protective Screen |
G6RL |
|
Figure 8. Protective Screen for One Pipe
Installations
11