A look at cost of ownership for dampers!
There are so many options available for dampers. Triple-V Steel, extruded aluminum airfoil, blade and jamb seals, insulation, etc. Lots to think about! For this post, I’m going to boil it down to a single factor, leakage.
AMCA 511 categorizes dampers based off their leakage rates at defined pressure. The table below outlines requirements for the four (4) classes of dampers, Class 1A, 1, 2 & 3.
When you’re selecting dampers for a building, it is important to look past the initial cost. To help you make a more informed decision, I’ve put together the following table comparing cost of ownership for a 48”x48” damper applied in an intake louvre application.
| 48″x48″ Damper, 1″ W.G. | Class 1A | Class 1 | Class 2 | |
| Aluminum Airfoil, Insulated | Aluminum Airfoil | Steel Roll-formed Airfoil | Steel V-Blade w/ Jamb Seals | |
| Initial Cost | $945.00 | $700.00 | $620.00 | $420.00 |
| Leakage Rate (CFM/ft2) | 0.5~ | 3 | 4 | 10 |
| Damper Leakage (CFM) | 8 | 48 | 64 | 160 |
| Total Leakage (ft3) | 49280 | 295680 | 394240 | 985600 |
| Time Closed (hrs) * | 6160 | |||
| Annual Heat Loss ^ | $14.01 | $84.07 | $112.10 | $280.25 |
| 1 Year Cost of Ownership | $959.01 | $784.07 | $732.10 | $700.25 |
| 10 Year Cost of Ownership | $1,085.10 | $1,540.70 | $1,741.00 | $3,222.50 |
| Notes: | ||||
| ^ Degree Day calculation with Gas @ $1.06/therm | ||||
| * Assumed occupied times for a typical office building with 5 day work week. (10-hrs) All other hours the dampers are closed | ||||
| ~ Tested leakage rate of Ventex 3960 damper. | ||||
This chart takes a very simplified approach to comparing different damper classifications. You’d have additional savings associated with the better damper, especially in buildings with cooling and humidification. I also haven’t considered the affects of damper degradation over time. It isn’t unusual to see lots of sunlight thought an old steel triple-V damper. Aluminum airfoil dampers stand the test of time much more effectively, maintaining the integrity of their seals much longer.
With a simple payback of <3years, it’s clear that using an extruded aluminum damper with Class 1A leakage rating is money well spent. Where communicating with the outdoors, adding insulation is also highly recommended.
If you want help selecting the right damper for your next project, contact O’Dell HVAC Group.
