Brugsvejledning Directions for use Bedienungsanweisung ... - Velux

Tips for fault localizationPump is overheated, but no heat transfer fromcollector to the store, feed flow and return flow areequally warm, perhaps also bubble in the lines.Pump starts for a short moment, switches-off,switches-on again, etc.Air in the system ?noyesIs the collector circuitplugged at the dirt trap?yesBleed the system; theprimary pressure of theexpansion tank has toexceed the static pressureby approx. 0,5 bar, thesystem pressure has toexceed it by approx. 0,5up to 1 bar (depending onthe dimensioning of theexpansion tank); switchthe pump on and off fora short time.Clean the dirt trapIs the temperature differenceat the controllertoo small?noyesWrong placing of thecollector sensor?noyesPlausibility control ofthe option tubecollector specialfunction?Change ∆Ton and ∆Toffaccordingly.noo.k.Mount the collectorsensor at solar feed flow(warmest collectoroutput); use theimmersion sleeve of therespective collector.Pump starts up very late and stops working soon.The temperature difference between store andcollector increases enormously during operation; thecollector circuit cannot dissipate the heat.Switch-on-temperaturedifference ∆Tontoo large?noyesChange ∆Ton and∆Toff accordingly.Collector circuit pumpdefect ?noyesControl / replaceCollector sensor unfavourableplaced e.g. contactsensor instead ofimmersion sleeve sensor?yesIf necessary activatetube collector function.o.k.Heat exchangercalcified?noyesHeat exchangerplugged?DecalcificationnoyesCleanHeat exchangertoo small?yesNew calculation of thedimension.59 VELUX