PVI Industries PV500-44U - Manual (Page 20)

20
PV500-44U 06/12
WARNING: Do not vent this water heater into an existing or traditional gas vent or chimney or combine the
vent with any other appliance. Such venting could result in failure of the venting system and/or exposure to
carbon monoxide which can result in property damage, personal injury or death.
9.3 Maximum Category IV Vent Length
(Equivalent Length)
A vertical or horizontal remote Category IV vent system must be used with this appliance. The maximum length of
field supplied Category IV vent is shown in the chart below titled Category IV Vent Equivalent Length.
Maximum Category IV Vent Equivalent Length
Vent Size 6” Vent 7” Vent 8” Vent 9” Vent
Max Equivalent Length 100 feet 130 feet 250 feet 450 feet
Pipe fittings reduce the maximum allowable vent length. Use the Category IV vent manufacturer’s equivalent length
deduction for all elbows, terminations, etc. If the information is not readily available from the vent manufacturer, use
the Vent Fitting Equivalent Length chart below to find the total equivalent length for all vent fittings in your
combustion air system. Then subtract this number of feet from the total equivalent length allowed in Maximum
Category IV Vent Equivalent Length chart above. The sum of this calculation is the maximum length of straight vent
allowed. If a longer length is required, repeat the calculation using a larger vent size. When using this chart, no
additional deduction is required for the addition of the vent system terminal.
The following vent information is provided for use in design calculations, if needed.
Venting Specifications
Input MBtu
Combustion Air
Volume (cfm)
Max Vent
Press. ”W.C.
399 136 0.5
500 170 0.6
750 255 1.0
900 306 1.2
1000 340 1.3
9.4 CPVC Vent System Design, Construction and Assembly:
The Power VT Plus water heater can be vented either vertically, through a ceiling or roof, or horizontally through a
wall. The solid CPVC, (CPVC not allowed on models with “SANI” in the model number) or stainless steel venting
listed by a nationally recognized testing laboratory for Category IV positive pressure gas appliance venting can be
routed to the outdoors in any direction, from the flue outlet of the water heater economizer, except down. The vent
must be installed and supported every four feet to slope downward toward the water heater vent connection with at
least ¼ inch drop per linear foot of horizontal vent run, to allow proper drainage of accumulated condensation.
1. Read and follow the information, instructions and warnings in “VENTING” section.
2. Do not insulate the plastic vent pipe.
3. Clean and deburr all solid CPVC (plastic pipe not allowed for venting models with “SANI” in the model number)
pipe ends and the joint area and trial assemble the vent before joining with CPVC cement, following the CPVC
cement manufacturer’s instructions for making sound air and water tight joints.
Vent Fitting Equivalent Length
Vent Pipe: 6” Vent 7” Vent 8” Vent 9” Vent
90º Elbow 8 feet 9 feet 10 feet 11 feet
90º Long Radius Elbow 5 feet 5 feet 5 feet 6 feet
45º Elbow 5 feet 5 feet 5 feet 5 feet