TM
Installation & Service Manual
2General venting (continued)
Minimum / Maximum allowable combustion air and vent piping lengths are as follows:
Vent = 12 equivalent feet minimum / 100 equivalent feet maximum
Combustion Air (when used) = 12 equivalent feet minimum / 100 equivalent feet maximum
When determining equivalent combustion air and vent length, add 5 feet for each 90° elbow and 3 feet for each 45° elbow.
EXAMPLE: 20 feet of PVC pipe + (4) 90° elbows + (2) 45° elbows + (1) concentric vent kit (CVK3003) = 49 equivalent feet of piping.
Table 2C Equivalent Vent Lengths
Model | Kit | Equivalent | |
Number | Vent Length | ||
| |||
3 feet | |||
The Shield water heater vent and air piping can be installed through the roof or through a sidewall. Follow the procedures in this manual for the method chosen. Refer to the information in this manual to determine acceptable vent and air piping length.
Air contaminationPool and laundry products and common household and hobby products often contain fluorine or chlorine compounds. When these chemicals pass through the water heater, they can form strong acids. The acid can eat through the water heater wall, causing serious damage and presenting a possible threat of flue gas spillage or appliance water leakage into the building.
Please read the information given in Table 1A, page 10, listing contaminants and areas likely to contain them. If contaminating chemicals will be present near the location of the water heater combustion air inlet, have your installer pipe the water heater combustion air and vent to another location, per this manual.
CVK3007 | 3 feet | |
|
|
|
CVK3007 | 5 feet | |
|
|
|
CVK3007 | 30 feet |
Removing from existing vent
Follow the instructions in Section 1, page 11 of this manual when removing a water heater from an existing vent system.
WARNING
WARNING
If the water heater combustion air inlet is located in a laundry room or pool facility, for example, these areas will always contain hazardous contaminants.
To prevent the potential of severe personal injury or death, check for areas and products listed in Table 1A, page 10 before installing the water heater or air inlet piping.
Vent and air piping
Vent and air system:If contaminants are found, you MUST:
• Remove contaminants permanently. |
NOTICE
Installation must comply with local requirements and with the National Fuel Gas Code, ANSI Z223.1 for U.S. installations or CSA B149.1 for Canadian installations.
• Relocate air inlet and vent terminations |
to other areas. |
You may use any of the vent/air piping methods covered in this manual. Do not attempt to install the Shield water heater using any other means.
WARNING DO NOT mix components from different systems. The vent system could fail, causing
leakage of flue products into the living space. Use only PVC or CPVC and fittings, with primer and cement specifically designed for the material used.
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