ESIE05-03 Functional DiagramsPart 1 – System Outline 1–2931453.7 Re-using Existing Field PipingIntroduction When installing a system using an RZQ outdoor unit, existing or pre-installed piping can be usedaccording to below specified conditions.In all circumstances where these conditions can not be fully met, new piping has to be installed.How to re-useexisting piping?Notes: Oil contamination can be checked using the Daikin “Oil Checker Card”.Caution: P If copper piping is corroded, existing piping re-use is not allowed.P Single side thermal insulation is not allowed for re-use.P See further notes in this section for Twin, Triple and Double Twin applications.Check the existingpipe size.Check the existing pipe length.See if the already installed air conditioner can operate and perform apump-down operation.After 30 minutes of cooling operation, proceed with pump-down operationwithout interruption.Check the compressor (of the existing air conditioner) for fault records.Remove the existing air conditioner.See if the contamination inside the existing pipe is acceptable.Rework the flare. (For R410A: See table )Use the supplied flare nut.Existing piping work for new air conditionerNon-standardsizeAll satisfactoryLonger than 50 mStandard size50 m or lessNoneExistNOOKBoth operation and pump-down are possibleOperation not possiblePump-down operationnot possibleNot listedBeyondallowablelength rangeNo tolerancefor capacityreductionReuseofexistingpipenotallowedCheck the existing pipe size and thicknessreferring to the "(1) SELECTION OF PIPINGMATERIAL" (on the next page).Check the following item in"(2) REFRIGERANT PIPE SIZE" and"(3) ALLOWABLE PIPE LENGTH ANDHEIGHT DIFFERENCE" (on the next page)See if the length requirements for re-usingthe existing piping are as specified.See if the reduction of cooling capacitymay cause any problem.on page 1–31.on page 1–30.on page 1–33.
