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12OPERATIONWinter:Humidity control is very important during the wintermonths. This is when problems will be most apparentsince condensation on the windows will often occur. Thecolder the outside temperature, the greater the risk ofcondensation in the home. The average relative humidityshould be maintained between (30-60) to avoid conden-sation. Low speed continuous ventilation with high speedoverride is recommended.A Heat Recovery Ventilator (HRV) is designed to bring fresh air into a building while exhausting an equal amount of stale air. During the wintermonths, the incoming cold fresh air is warmed by utilizing the heat recovered from the stale air before it is exhausted to the outdoors. During sum-mer months when the indoor space is air conditioned, the HRV will help in cooling the incoming fresh air with the stale air that is being exhausted.Powrmatic HRV’s are designed to run continuous or on intermittent, giving the homeowner complete control over their air quality. Continuouslow speed ventilation is recommended, which will help eliminate carbon dioxide, voc’s and other gases as well as freshen up the home.Intermittent high speed ventilation can be obtained through a variety of optional remote controls found in this manual. Below are some examplesof seasonal operation of an HRV.Spring:Temperatures are more moderate and becomewarmer each day. To keep the humidity and tem-perature uniform, set the dehumidistat higher (ifinstalled). You may also switch the HRV to standbymode if desired.Summer:The air is sometimes hot and humid. To stop the warmhumid air from entering, set the dehumidistat at itshighest level. If the Intellitek series controller isinstalled, the air exchanger can be set to cycle the uniton and off as desired from that wall control. However,continuous ventilation is recommended.Fall:Rain and rapid temperature changes make it diffi-cult to control the internal humidity level and mayresult in condensation on the windows. A remotedehumidistat may help give greater control over theinside environment.The entire line of SHR/VHR series Heat Recovery Ventilators comes equipped with Fantech's new electronic uni-control board which offers a widevariety of features making it the ultimate ventilation control system. Fantech engineers have used the latest technology to provide solid, trouble freeoperation under any conditions.The Fantech uni-control board offers stand alone operating capabilities as well as an exclusive 2 wire communication to most external controls. Thetrouble-free optional controls include: two different rotary dial dehumidistats, an air quality sensor (3 wire communication required), a 15 minuteremote push-button timer, as well as the most sophisticated line of remote wall mounted controls, the Intellitek 5MR.An on-board diagnostic LED helps find problems quickly and efficiently. For example the LED can be used to signal a broken or shorted electronicwall control wire. Electronic air temperature probe gives this board accurate readings in order to minimize unnecessary defrost operation, and theon-board jumpers provide the user with the option of adjusting defrost time and sequence to optimize performance under abnormal conditions. Thedefrost operation is automatic and is usually never adjusted.2. Defrost (SHR/VHR Models)The automatic defrost cycleSHR/VHR models of HRVs consistsof a fan shutdown. When the supplyair stream temperature goes below-5°C (23°F), the supply motorshuts down and the exhaust motor goes into high speed. Ambient air ispassed through the unit for a period of 5 minutes. The supply motor willthen re-start and run at the preset speed. The exhaust motor will alsoslow down to the preset speed, and the unit will operate in the run cyclefor 25 minutes. This fan shutdown defrost cycle continues until the sup-ply air stream rises above 0°C (32°F).MODES OF OPERATION1. Continuous / Ventilation ModeIn this mode of operation both fansare operating and exchanging air withthe outside. The heat recovery venti-lator (HRV) constantly exchanges theair at the rate you select, either at low or medium speed, and switchesto high speed when activated by an optional remote control. The "Low"and "Med" fan speed selection will cause the unit to operate in continuousexchange mode at an exchange rate of 35% and 50% maximum airflowrating respectively. Continuous mode is recommended, since pollutantsare slowly but constantly being generated in your house.Air fromHouseAir fromOutsideAir toHouseAir toOutsideAir fromHouseAir tooutside