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PART 4. VENTING
C. INLET AIR VENT
You may use the same material as used for exhaust or any material that is the same diameter that provides a
pressure tight connection. THIS IS ONLY FOR INLET AIR, NOT FOR EXHAUST PIPING!
The air inlet must be a minimum of 12" vertically above the maximum snow level. It is very important that there are
no other vents, chimneys or air inlets in any direction for at least 48".
All venting must be properly supported. The EVO is not intended to support any venting whatsoever.
All
piping, glue, solvents, cleaners, fittings and components, must conform to ASTM (American Society for Testing and
Materials), and ANSI (American National Standards Institute).
D. VENTING RUNS THAT EXCEED MAXIMUM COMBINED LENGTH
If the combined venting length of a heater’s exhaust/inlet air system exceeds the Maximum Combined
Length called out in Table 4-1, Page 23, contact Hamilton Engineering, Inc. for an engineered venting
calculation. Do not proceed without calling Hamilton Engineering Co, Inc. at 800.968.5530.
VENT CALCULATION EXAMPLE: Installation requires the following material for both inlet and
exhaust piping for the EVO HW 299 (maximum combined equivalent length is 225 feet).
Required: 6 Pcs. 90° elbow (6 x 5 = 30 equivalent feet)
= 30 equivalent feet
Required: 20' of Plastic PVC Pipe (20 x 1 = 20 equivalent feet)
= 20 equivalent feet
Required: Inlet air in vertical termination (2) 90° bird screen) = 11 equivalent feet
Required: Exhaust coupling
= 1 equivalent foot
Total Friction Loss in equivalent feet
= 62 equivalent feet
E. HEATER REMOVAL FROM AN EXISTING COMMON VENT SYSTEM
At the time of removal of an existing heater, the following steps shall be
followed with each appliance that remains connected to the common
venting system placed in operation, while the other appliances that
remain connected to common venting system are not operating.
1. Seal any unused openings in the common venting system. The EVO
venting is NOT to be combined with this older venting system!
2. Visually inspect the venting system for proper size and horizontal pitch to
determine if there is blockage, leakage, corrosion or other deficiencies that
could cause an unsafe condition.
THIS VENT SYSTEM IS OK!
The EVO is not intended to be common
vented with any other existing appliance!
Multiple EVO products may be common
vented, only if using an engineered system
by Hamilton Engineering Company, Inc.
DANGER