Backflow Certification TREEO Center,
UF Questions and Correct Answers
What is the correct height to install an air gap ? - <CORRECT ANSWER >>Two times the nominal
diameter of the supply pipe or a minimum of 1 inch .
What are the components of a RP ? - <CORRECT ANSWER >>Two independently operating
check valves , a relief valve assembly , four test cocks and two shut - off valves .
What are the components of a DCVA ? - <CORRECT ANSWER >>Two independently operating
check valves , four test cocks and two shut - off valves .
What is the definition of backsiphonage ? - <CORRECT ANSWER >>Backflow caused by a drop in
supply pressure below atmospheric pressure .
The RV drips after closing customer's shut - off valve . Why ? - <CORRECT ANSWER >>CV # 1
leaks
What causes the RV to spit ? - <CORRECT ANSWER >>Line pressure fluctuation .
If there is backpressure on the RP what does the RV do ? - <CORRECT ANSWER >>Nothing
unless CV # 2 leaks .
If there is a drop in supply pressure what does the RV do ? - <CORRECT ANSWER >>Opens to
dump the zone .
What holds the Relief valve open ? - <CORRECT ANSWER >>Relief valve spring .
What holds the Relief valve closed ? - <CORRECT ANSWER >>Supply pressure .
, Relief valve does what if outlet shut - off valve leaks ? - <CORRECT ANSWER >>Relief valve tries
but may not open when being tested .
In test # 3 on the RP , open vent control and the gauge needle rises , what's wrong ? -
<CORRECT ANSWER >>The outlet shut - off valve leaks with backpressure .
HowIIdoIIyouIIknowIIifIItheIIoutletIIshutII-IIoffIIvalveIIleaksII?II-
II<CORRECTIIANSWERII>>1.IITheIIRVIImayIInotIIopenIIwhileIItestingII
2.IITheIImeterIIisIIrunningII.II
3.IIYouIIcanIIhearIItheIIwaterIIrunningII.
CanIIyouIItestIItheIIRPIIwithIIwaterIIflowingIItoIItheIIcustomerII?II-
II<CORRECTIIANSWERII>>NoII,IItheIIassemblyIImustIIbeIIstaticII.
WhatIItypeIIofIIgaugeIIdoIIyouIIuseIItoIItestIItheIIRPII?II-
II<CORRECTIIANSWERII>>DifferentialIIPressureIIGaugeII.
HowIIdoIIyouIIbreakIIorIIstopIIbacksiphonageII?II-II<CORRECTIIANSWERII>>AddIIairII.
WhatIIisIItheIImostIIimportantIIstepIIbeforeIIinstallingIIanIIassemblyII?II-
II<CORRECTIIANSWERII>>FlushingIIsupplyIIlineIIofIIdirtIIandIIdebrisII.
WhyIIinstallIIassembliesIIinIIparallelII?II-
II<CORRECTIIANSWERII>>ToIImaintainIIserviceIIwhileIItestingIIorIIrepairingII.
AtIIwhatIIheightIIshouldIIRPIIbeIIinstalledII?II-
II<CORRECTIIANSWERII>>MinimumII12II"IItoII36II"IIaboveIIgradeII.
UF Questions and Correct Answers
What is the correct height to install an air gap ? - <CORRECT ANSWER >>Two times the nominal
diameter of the supply pipe or a minimum of 1 inch .
What are the components of a RP ? - <CORRECT ANSWER >>Two independently operating
check valves , a relief valve assembly , four test cocks and two shut - off valves .
What are the components of a DCVA ? - <CORRECT ANSWER >>Two independently operating
check valves , four test cocks and two shut - off valves .
What is the definition of backsiphonage ? - <CORRECT ANSWER >>Backflow caused by a drop in
supply pressure below atmospheric pressure .
The RV drips after closing customer's shut - off valve . Why ? - <CORRECT ANSWER >>CV # 1
leaks
What causes the RV to spit ? - <CORRECT ANSWER >>Line pressure fluctuation .
If there is backpressure on the RP what does the RV do ? - <CORRECT ANSWER >>Nothing
unless CV # 2 leaks .
If there is a drop in supply pressure what does the RV do ? - <CORRECT ANSWER >>Opens to
dump the zone .
What holds the Relief valve open ? - <CORRECT ANSWER >>Relief valve spring .
What holds the Relief valve closed ? - <CORRECT ANSWER >>Supply pressure .
, Relief valve does what if outlet shut - off valve leaks ? - <CORRECT ANSWER >>Relief valve tries
but may not open when being tested .
In test # 3 on the RP , open vent control and the gauge needle rises , what's wrong ? -
<CORRECT ANSWER >>The outlet shut - off valve leaks with backpressure .
HowIIdoIIyouIIknowIIifIItheIIoutletIIshutII-IIoffIIvalveIIleaksII?II-
II<CORRECTIIANSWERII>>1.IITheIIRVIImayIInotIIopenIIwhileIItestingII
2.IITheIImeterIIisIIrunningII.II
3.IIYouIIcanIIhearIItheIIwaterIIrunningII.
CanIIyouIItestIItheIIRPIIwithIIwaterIIflowingIItoIItheIIcustomerII?II-
II<CORRECTIIANSWERII>>NoII,IItheIIassemblyIImustIIbeIIstaticII.
WhatIItypeIIofIIgaugeIIdoIIyouIIuseIItoIItestIItheIIRPII?II-
II<CORRECTIIANSWERII>>DifferentialIIPressureIIGaugeII.
HowIIdoIIyouIIbreakIIorIIstopIIbacksiphonageII?II-II<CORRECTIIANSWERII>>AddIIairII.
WhatIIisIItheIImostIIimportantIIstepIIbeforeIIinstallingIIanIIassemblyII?II-
II<CORRECTIIANSWERII>>FlushingIIsupplyIIlineIIofIIdirtIIandIIdebrisII.
WhyIIinstallIIassembliesIIinIIparallelII?II-
II<CORRECTIIANSWERII>>ToIImaintainIIserviceIIwhileIItestingIIorIIrepairingII.
AtIIwhatIIheightIIshouldIIRPIIbeIIinstalledII?II-
II<CORRECTIIANSWERII>>MinimumII12II"IItoII36II"IIaboveIIgradeII.
