Carrier 38HB series Installation, Operation And Maintenance Instructions

Contents

Carrier 38HB series Installation, Operation And Maintenance Instructions Manual pdf 10 page image

• Soft starter detail (optional):Soft starter of the supply centrifugalfan which prolongs the set time,available for indoor units 40HB/HF.It’s mainly aimed at installations withcloth ducts.Pulley and belt calibrationAttention: Before performing these operations, it is necessary to verifythat the unit is disconnected from mains.Centrifugal motorfans are coupled with pulleys and belts.In this type of fans, the following must be taken into consideration:- The pulleys must be on the same plane, so it is important to checkthem with the help of a ruler or a laser aligner.- In case they are not aligned, remove the pulley screws, remove thepulley and, after removing the taper pin, it can be slid over the axle(this action can be performed both in the motor as well as in the fan).- After fixing the pulleys on the same plane, the belt tension is madeby tightening the tensor screw.- The belt tension must be checked after 24 hours of motor operation.Che ck s in t he c e nt rifuga l fa ns- Before commissioning, check the blade rotation direction and thatthe axis turns without strokes nor vibrations- Once running, check the operation conditions: pressures, flows andconsumptions.- The overlapping of characteristic curves of the fan and the room isvery important, so that the flows and pressures provided to the ductnetwork are as required.Pulleys must stay on the same planeTensorscrewPulleyscrewsTaper pinCaution: Indoor units are designed to connect to a ductnetwork. In the event that the outlet fan of the indoor circuitis accessible from a particular point in the duct network, theinstaller must install a protection mesh in the discharge asper the current regulation.Air duc t s c onne c t ionsThe air supply and return ducts must be calculated in accordance withthe rated flow and the unit’s available pressure (refer to the technicalcharacteristics table). The duct calculation and design must be madeby qualified technical personnel.It is advisable to take into consideration the following recommendations:- Curves in the fan supply outlet(s) must be avoided. It isrecommendable to have a straight section of duct measuringapproximately 1 metre. If it is not possible, they must be as smoothas possible, using indoor deflectors when the duct is of largedimensions.- When making the ducts, direction sharp changes must be avoidedsince they can generate occasional pressure drops, which affectthe available pressure and the flow. The location of discharge andaspiration grilles must be studied carefully to avoid the air recirculationand the transmission and generation of noises to the interior.- Flexible connections must be made between the ducts and the unitthat avoid the noise and vibration transmission.- No matter the type of ducts type to use, these must be insulatedand not be composed of materials that propagate fire nor expel toxicgases in the event of a fire. The internal surfaces must be smoothand should not pollute the air that circulates within them. In any case,the effective legislation about this issue must be respected.Split-system cooling unitsand heat pumps10