SMARTVENT®
"The smartest ventilation system in this world."

SmartVent® is a 24 hour watchdog. Around the clock it compares temperature, relative humidity, and water vapor in crawl space and outside air. You need all this information to ventilate effectively.

SmartVent® waits until the outside air has less moisture than the crawl space air. Then the high capacity fans suck out wet air, replacing it with drier air, trying to dry the under-home structure, to prevent foundation and subfloor wood rot.

Depressurizing the crawl space slightly exhausts undesirable gases, odors, chemicals (termiticides), and radon that migrate into the home.

Depressurization also helps those who have allergies triggered by molds, spores, and bacteria growing in areas of excessive humidity.

SmartVent® saves the homeowner heating and cooling energy costs, helps prevent pipes from freezing.

Not only will the SmartVent® reduce crawl space moisture when it's too high, but to help prevent buckling and splitting of hardwood floors, the SmartVent® can even pump moisture back into the crawl space when the crawl space moisture is too low.

Your crawl space is continually bathed with wet air. Though some of the moisture in crawl space comes from the ground, most moisture entering a crawl space is airborne, passing through the block walls, open or closed foundation vents, and every small opening around rim joists.

Having your crawl space vents always open or always closed is a lousy way to ventilate a crawl space. You might be ventilating when it is raining. You may be ventilating when it is freezing, and, most importantly, warm air always can hold much more moisture than colder air.

When warm outside air is brought in to a cooler air space (a crawl space), as the air cools to crawl space temperature, humidity skyrockets. Even if the outdoor air has a lower relative humidity than the crawl space air, when the outdoor air has cooled to crawl space temperature, the humidity goes up.

An example: If the outdoor air is 95°f and 45% relative humidity, when that air cools to crawl space temperature, the relative humidity becomes 95%.

By collecting all the information of temperature, humidity, and water vapor content of both inside and outside air, The SmartVent® is smart enough so it never starts a ventilation cycle unless it has a drying effect on crawl space.

Technical Description

SmartVent® is an electronic ventilator with state-of the-art temperature, humidity, and moisture sensing of both crawl space and outside air. The on-board computer performs timing and comparison routines to decide when to ventilate and when not to ventilate.

The controller uses 120vac power, energizes efficient high capacity fans which use 15 watts when running. SmartVent® dimensions are 7 7/8" x 15 1/4" x 8" (just slightly smaller than a concrete block).

There are preset limits that must be fulfilled to ventilate.

Minimum outdoor temperature

>42° f

Then a decision is made to either decrease or increase crawl space relative humidity.

1. Increase crawl space relative humidity.
   
   If crawl space relative humidity is <25%, and outdoor air contains 20% more absolute total moisture than the crawl space air, a humidity increasing cycle is begun.
   
   
2. Decrease crawl space relative humidity.
   
   If crawl space relative humidity is >35%, and outdoor air contains the same or less absolute moisture than the crawl space air, a humidity decreasing cycle is begun.

The effect is to stabilize sub-floor moisture, helping protect hardwood floors from buckling or splitting, and still provide as much ventilation as possible without worsening the condition in the crawl space.

Step 1. Outdoor air is sampled. If outside temperature is inside preset limits mentioned, outdoor temperature, humidity, and vapor pressure are recorded. If not the Smartvent waits until limits are met.

Step 2. A fan comes on to draw crawl space air across the sensors. After 2 minutes crawl space temperature, humidity, and vapor pressure are recorded.

Step 3. Comparison is made. A 106 minute timer is started. If conditions are favorable to ventilate, both fans run. If unfavorable, both fans are off.

Step 4. At the end of 106 minutes, fans are off for 15 minutes. Then Step 1 begins again.

Two LED lights indicate the part of the sequence the Smartvent is executing.

• Each LED alternates flashing slowly - Sampling outdoor air. (15 minutes or as long as outside air exceeds preset limits.)
• Each LED alternates flashing rapidly - Sampling crawl space air. (A single fan runs.)
• Both LEDs on continuously - Ventilating 106 minutes. (Both fans are on.)
• Both LEDs flashing together slowly - Wait 106 minutes. It is not favorable to ventilate.
• Both LEDs flashing together rapidly - Manual override mode.

Only one SmartVent® needs to be installed for a crawl space. The SmartVent® is installed just the same as any other foundation vent, and must be cemented securely in place prior to applying electrical power. Installation can also be done with 35 year, clear, outdoor caulk, instead of cement.

The SmartVent® louvers are to be wide open. Close the louvers on your other foundation vents. We think closing the louvers of all other vents is best. The reason is, air takes the path of least resistance, so if there is a vent wide open in close proximity to the Smartvent, that opening will provide most of the incoming air. By closing louvers down by hand (not sealing them) slots are left between louvers. When the fan comes on, the static pressure of the fan is sufficient to draw air in from all your vents rather than just one or two.

Have a qualified electrician make the electrical connection/service needed.

The SmartVent® consumes only 40 watts when it is running (about 1/10th amp), so it can be added to any 115 volt circuit. Or you may wish to have an electrician put it on a separate circuit breaker, to easily turn power off during installation. A separate on/off circuit (or switch) permits easy checkout of ventilator (see below).

We provide a 6' power cord so you can plug one end of the cord into the 120 volt receptacle, the other end into the back of the Smartvent.

First, remove an existing vent, carefully chipping away the mortar so brick isn't damaged. Clean up the opening.

Plug in cord into recptacle, pull power cord through opening, plug into Smartvent, put the Smartvent in the opening flush with the outside, then seal around completely with 50 year outdoor clear silicone caulk.

Open the Smartvent's louvers wide open.

We think the outdoor silicone is better than mortar, fast, easy to clean up. Looks great. The sealing, cleanup is about 30 minutes. What's it take to remove an existing foundation vent? I would guess the entire replacement job is an hour or so. You might ask your termite person how much it costs to replace an existing foundation vent. (His estimate will likely be for mortar rather than silicone. That's how they have always done it.)

What I've described is, perhaps, a do-it-yourself project if you already have the electricity.

A ground lead can be connected to any screw on back of housing. Push the assembly into the block opening, and secure with cement or outdoor, clear caulk.

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Can the ventilator be checked to see if it working? Yes.

A sequence runs if all sensors are communicating correctly with the computer.

When power is first applied, the fan turns on for about 1 second, then turns off. This occurs only if all parts are communicating correctly. In about 15 seconds normal operation begins..

SmartVent® begins its normal sequence of operation if the outside temperature is over 40°f. A fan then runs for 2 minutes. Then the microprocessor decides whether or not to proceed with a ventilation cycle (and whether to increase or decrease humidity).

Smartvent, Inc.
3255 Cimarron Drive
Conway, AR 72032

Web: http://www.smartvent.net
Phone: 501-329-4915
E-mail: sales@smartvent.net