37EnglishField Setting ModeAdditional heating option : 40**Heat Pump Variables for Space Heating࡙ FSV #4011 for DHW priority is set to "0(DHW)" (Default) as a default. Space heating gets a priority bysetting FSV #4011 "1", but this is only valid when the outdoor temperature is lower than the specifiedtemperature defined by FSV #4012.࡙ Cold weather compensation is applied when the space heating gets a priority (FSV #4011=1). It is dueto position of heating coil and booster heater in the water tank. Heating coil is at the bottom part ofthe water tank and the booster heater is located at the middle part of the tank. So the heating coil isefficient to heat the whole water in the tank. Chances that hot water flows through the heating coildecrease with the space heating priority. And lower part of water in the tank might not get enough heatwith the booster heater.࡙ƊΧɇʀʪ˵ʪɇϩ̈͝˝ͱ˙˙ϩʪ͔ΧʪθɇϩЇθʪ࣍ƊǤࡡߤߢߡߥࢄUʪ˙ɇЇ̷ϩߦߥࢥߦߤઑAࡡŵɇ͝ ˝ʪߥߢॄߦߥࢥߦߤઑA࣎ࡠϩ˵̈˝˵ͱЇϩʒͱͱθtemperature above this value, the space heating will be turned off, to avoid overheating.Backup Heater Variables for Space Heating࡙ The FSV #4021 should be set to 1(Yes) to use 2-stage electric backup heater in hydro unit as anadditional heat source. (If FSV # 4021 is 2, a 1-stage electic backup heater is used)࡙ To compensate the lowered heat pump heating performance under very cold weather conditions, theFSV #4023 should be set to "1(On)"(Default). ࣕThe threshold temperature to use backup heater for cold weather compensation: FSV #4024, DefaultߡઑAࡡŵɇ͝˝ʪࣗߦߣॄߦߤઑA ࣕThe backup heater operation is restricted to save energy in the threshold temperature range.࡙ The FSV #4022 for backup heater priority should be set to "0 (both)" (Default) or "1" (backup) to usebackup heater. If not (booster heater priority), the backup heater can be operated in case of no boosterheater demand.࡙The threshold temperature for backup heater operation during defrost mode to prevent cold draftbecause of chilled water can be controlled by adjusting FSV #4025. Under FSV #4025 of water outlettemperature, backup heater Will be turned on.NOTE࡙ To use both heaters together at the same time, please check the capacity of the power circuit breaker ofyour house before use.External Backup Boiler for Space Heating (Field Option)࡙ The FSV #4031 should be set to "1 (Yes)" to use a backup boiler as an additional heat source.(default: "0 (No installation)")࡙ Priority of backup boiler and heat pump is defined by FSV #4032 (default: "0 (OFF)")࡙ To compensate the lowered heat pump heating performance under very cold weather conditions, thebackup boiler operates instead of heat pump under the threshold temperature (FSV #4033, Default ࣗࢋઑA࣎ߦॄߡߣࣗŵɇ͝˝ʪࡡઑAߦߢ