Vent Riser™

Sub-grade Venting Just Got Easier!

• Ensures the vent termination is above grade and in compliance with codes
• Perfect for basement installations where a window well must be used or when a vent terminal cannot be mounted to maintain a minimum 12” clearance above grade
• Stainless steel construction
• Combustion air connection rotates 360° for easier installation



For basement installations where a window well must be used, or in installations where the vent terminal cannot be mounted to maintain the minimum 12" clearance above grade, use a Field Vent Riser™

How to determine total equivalent feet



Dimensions
Model A B C D E F G H
CV-4VR 42 1/16" 33 1/2" 17 3/4" 9" 6 3/8" 44" 10 1/2" 12 1/2"
CV-5VR 42 1/16" 32 1/4" 20 3/8" 9 5/8" 6 7/8" 44" 10" 12 7/8"


Specifications
Model Volts Hz Amps Watts RPM Thermal Protection
CV-4VR 115 60 1.7 138 3000 YES
CV-5VR 115 60 1.3 144 3100 YES

How to determine total equivalent feet
1. Determine the total equivalent feet for each type of fitting used in the venting system from Tables 1 and 2.
2. Calculate the total feet for the straight lengths
of pipe.
3. Add the equivalent feet of the fittings to the total amount of feet of straight length pipe. This will approximate the total equivalent feet of the vent system.
4. Find your total equivalent feet in Table 3 to determine the proper model for your installation.

Example: System Pipe Size= 6"
Step 1 2-90° Elbows (6")= 22 Ft.
Step 2 10-2 Ft. Lengths of 6" Pipe = 20 Ft.
Step 3 6" to 4" reducer= 4 Ft.
Step 4 Total Equivalent Feet= 22 Ft. + 20 Ft. + 4 Ft. = 46 Ft.

Table 1 - Equivalent Feet for Vent Pipe Fittings
VENT PIPE FITTINGS VENT PIPE DIAMETER
4" 5" 6" 7"
Tee 25 31 38 44
Y-Connection 13 16 20 23
90° Elbow 7 9 11 12
45° Elbow 4 4 5 6


Table 2 - Equivalent Feet for a Reducer/Increaser
PIPE SIZE
Large Small
4" 5"
4" 0 -
5" 2 0
6" 4 2
7" 5 4
To estimate the equivalent foot length of the Reducer/Increaser chart, find the figure at the intersection of the small pipe size and the large pipe size.


Table 3-Sizing The Vent Riser (Use Maximum GPH Input)
MODEL MAX* OIL GPH INPUT 100psi MAX* OIL GPH INPUT 140psi MAX** GAS BTU/hr. INPUT AT MAX GPH INPUT AT 60% OF MAX GPH INPUT COMBUSTION AIR OPTION VENT PIPE SIZE
CV-4VR 1.10 .90 170,000 18 83 yes*** 4"
48 100 5"
100 100 6"
100 100 7"
CV-5VR 1.85 1.55 290,000 - 25 yes*** 4"
32 81 5"
76 100 6"
100 100 7"
* Oil: Select vent riser according to the actual rated maximum GPH input. ComboVent GPH ratings at 100 psi. Do not exceed maximum oil GPH input. ** Gas: Do not exceed maximum BTU/hr. input rating. For multiple venting system applications add the input for each appliance. Category I gas-fired draft induced systems require an CV-4 or larger. Category III gas-fired draft induced systems require a CV-5 or larger. Unit sizing may vary depending on specific application. Consult your dealer or factory representative for the proper sizing for your particular application. *** Do not use combustion air intake when using gas.
Note: In Table 3, the maximum equivalent footage allowable for the vent pipe is given for two points, the maximum GPH venting capacity and at 60% of the maximum. This allows for estimating values between the two given points.
contractorsidemenu