Exhaust fans typically have a gravity damper within the wall vent or a butterfly damper within the exhaust duct. The purpose of these backdraft dampers is to prevent outdoor air from making its way back into the house. The dampers only allow air to flow from the bathroom to the outside in one direction. During […]
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This article explains the differences between exhaust only, supply only, and balanced building ventilation. Additionally, this article has example calculations showing the differences between the ASHRAE 62.2-2010 and 2013 standard revision when sizing residential ventilation systems. Wiring diagrams show how to connect a ventilation controller to air handling units and bathroom exhaust fans. Ventilation sequence
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This article explains how to connect a Nest thermostat to control room temperature using a gas fireplace. Wiring diagrams are included for the two most common types of ignition systems found in gas fireplaces. These ignition systems include the millivolt ignition (standing pilot / continuous pilot) and the intermittent pilot ignition IPI (electronic ignition). Additionally,
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This article describes how HVAC duct sealing creates a more comfortable living environment while improving heating and cooling system efficiencies. Energy efficiencies increase by applying duct mastic to seal all forced air ductwork connections, seams, and joints. This includes all supply and return air ductwork internal or external to the building envelope. Fresh air supply
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This article describes how to receive instant hot water at all hot water faucets, showers and appliances within a building. No longer having to wait for hot water reduces water waste as well as lowers water utility bills. Installing a recirculation pump within the plumbing system is the only way to receive instant hot water
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This article describes how to measure and mitigate radon levels within your home. The two most commonly used methods for radon mitigation include Active Soil Depressurization “ASD” and Passive Soil Depressurization “PSD”. This article will also discuss how to perform the pressure field extension test required for Active Soil Depressurization arrangements. This test is also
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Phantom power Standby power Vampire power How much does standby, phantom and vampire power cost? Note Measuring energy consumption of standby and phantom power Step 1: Use a power quality analyzer to measure the total standby and phantom power consumed while all devices are plugged in and switched off Note Kill A Watt Electricity Usage
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This article explains what a cool roof is and how they work to reduce energy consumption. Solar reflectance and thermal emittance are the material properties that differentiate a cool roof from a conventional roof. Solar reflectance and thermal emittance determine the steady state temperature a roof will reach during a warm day. A roof’s steady
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Stapling radiant barrier foil to the bottom of attic roof rafters improves the thermal performance of attic insulation in hot climates. Radiant barriers reduce radiant heat gain, which results in lower air conditioning requirements as well as energy savings. Radiant heat transfer Everything with a temperature greater than 0oK emits radiant heat. Radiant heat primarily transfers
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