Compressor based dehumidification provided by Seresco results in up to
savings per year.
which could represent as high as
cost savings over a 15 year lifespan.
this is more than
the cost of new equipment.
Indoor Air Quality Comparison
Dilution VS. Source Capture
No Air Movement
Chloramines are 4 times denser than air, leading them to settle on the pool surface or “breathing zone”, like a layer of scum, in the absence of any air disturbance.
Dilution/100% Outside Air
The Dilution approach to indoor air quality requires bringing in large volumes of outside air, targeting the pool surface. This causes the chloramine layer to be disturbed and absorbed into the rest of the room, before finally being exhausted.
Source Capture
Source Capture introduces a gentle air current at the pool surface level, which exhausts the chloramine-laden air “at the source”, without distributing the chloramines throughout the pool room. Dehumidifiers manufactured by Seresco can be specified with the Source Capture ready option.
Cost Savings Analysis
Operating costs for natural ventilation dehumidifiers are heavily affected by climate.
0.4% DB/MCWB
| Dilution (constant outside air) | Dilution (constant outside air and compressor) | Source capture (compressor and optimized ventilation) | Compressor HP | Anuual savings | % reduction using source capture | |
|---|---|---|---|---|---|---|
| Denver | $ 66,952 | $ 70,034 | $ 43,481 | 20 | $ 26,553 | 40% |
| Minneapolis | $ 66,213 | $ 68,830 | $ 47,801 | 46 | $ 21,029 | 32% |
| Washington DC | $ 62,558 | $ 65,640 | $ 45,836 | 46 | $ 19,804 | 32% |
| Chicago | $ 64,493 | $ 66,945 | $ 46,611 | 46 | $ 20,334 | 32% |
| Atlanta | $ 59,464 | $ 66,845 | $ 45,353 | 38 | $ 21,492 | 36% |
| Dallas | $ 57,979 | $ 65,360 | $ 45,308 | 38 | $ 20,052 | 35% |
| Boston | $ 60,363 | $ 61,476 | $ 42,236 | 30 | $ 19,240 | 32% |
| Los Angeles | $ 58,405 | $ 58,617 | $ 37,904 | 20 | $ 20,713 | 35% |
| Average | $ 62,053.38 | $ 65,468.38 | $ 44,316.25 | Average reduction using source capture | $ 21,152.13 | 34% |
calculations are based on ASHRAE climate data.
0.4% DB/MCWB
calculations are based on ASHRAE climate data.
5 Common Myths of the Dilution Approach
The following myths used to sell 100% outside air (OA) can cost you money, yield dissapointing IAQ, and overall comfort.
Outside Air is more energy efficient and has lower operating costs
Calculations we have seen show OA to be more energy efficient incorrectly assume that compressors are operating at 100% 24/7, 365 days a year. Operating costs are 34% lower on average with compressor based dehumidification
Any location is suitable for Outside Air only
In most geographies 100% OA results in unfavorable space condition fluctuations for at least part of the year
Outside Air removes the need for compressor-based dehumidification
Many systems originally designed for 100% OA end up with a compressor to ensure more acceptable year round conditions
Adding more Outside Air than the code requires leads to better outcomes
Not only is it expensive and energy inefficient, it results in space condition fluctuations and does not necessarily provide better IAQ. In certain municipalities, this is in direct contradiction with green initiatives, and potentially code requirement
Outside Air results in better IAQ
Ineffective duct design will not be improved by adding more OA. There are many installations where operating in 100% OA mode results in poor IAQ as the OA does not get to where it is needed in the space. Volatile Organic Compounds such as trichloramines sit on the water surface (also known as the breathing zone), as they are heavier gases than the outside air added. This is why source capture solutions are a superior choice.
The Benefits of the Source Capture Approach
The dilution air approach was mostly abandoned in the 80s when people discovered the compressorized approach to controlling their space delivered more reliable results and saved energy. Source capture delivers superior indoor air quality without the need for bringing in more outside air than the code requires.