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Flushing/Descaling Procedures
1. Follow and understand all safety related information provided
with the tankless water heater as well as the flushing system
beforestartingtheflushingoperation. Wearappropriatesafety
apparelincluding safety glasses and rubber gloves. Inspect all
hoses and electrical cords for any kinks, cuts, etc. that could
resultinanelectricalshockhazardorfluidleakage. Replaceany
worn or damaged components. Consult appliance instruction
manual for complete flushing instructions.
2. Disconnect power to the tankless water heater, following the
instructions provided with the appliance.
3. Drain the water heater following the instructions provided with
the appliance.
4. Close the Cold Water Supply Valve and Water Heater Outlet
Valve, isolating the heat exchanger.
5. Connect a hose (supplied with the system) from the fitting
labeled “Pump Discharge” on top of the Flushing System to
the Service Valve on the Cold Water Supply side of the water
heater.
6. Connect a hose (supplied with the system) from the fitting
labeled “Return” on top of the Flushing System to the Service
Valve on the Hot Water outlet side of the water heater.
7. Remove the black threaded cap on top of the system and add
nomorethan 2 gallons of virginfoodgrade white vinegar to the
tank. Replacethethreadedcap. Makesuretheincludedo-ring
is properly seated in the cap to provide a leak proof seal.
8. OpentheHot and Cold Service Valves tothewater heater heat
exchanger.
9. PlugPower Cord from theFlushingSystemPumptoa properly
grounded electrical receptacle. Never allow the pump to run
without adequate liquid in the tank or possible damage to the
pump may occur.
10. Allow the pump to circulate the vinegar solution for at least 45
minutes or per the appliance manufacturer’s recommendation
(consult appliance instruction manual). Monitor the system for
leaks or any peculiar behavior. Unplug the power cord if the
pump stops, an external leak develops, or the flow is greatly
reduced.
11. After therequired time expires, unplugthepower cord from the
receptacle.
12. Close the Service Valve on the Cold Water Supply line and
disconnect the hose end from the Service Valve.
13. Disconnect the hose end from the Flushing System “Return”
Line Connection and route it to a suitable drain or to a bucket.
Connect an extra length of hose if necessary.
14. OpentheColdWaterSupplyValvetoflushthewaterheaterwith
fresh water, rinsing out the cleaning solution. Let the system
flushfor5minutesorasrequiredpertheapplianceinstructions.
Monitor the discharge from the hose. If using a bucket, empty
as needed.
15. After the required time expires, close the Hot Water Service
Valve and disconnect the hose.
16. Open the Hot Water Supply Valve.
17. Restore power to the heater system and return it to service.
After completing the flushing operation:
1. Discard the contents of the Flushing System by removing the
threadedcapfromoneofthetankaccessconnectionsonthetop
or side of the tank. Pour the contents into a suitable drain.
2. Remove the Return fitting from the top of the tank to access
the strainer assembly. The strainer element is connected to
the fitting with a hose clamp. Loosen the clamp to remove the
strainer. Discard the contents of the strainer and rinse away
any remaining particles. Inspect the strainer for any tears or
damage. Replace the strainer as needed. Order P/N 150786.
Re-assemble the strainer to the fitting assembly and tighten
clamp.
3. Replace the fitting assembly into the cover of the tank.
4. Add approximately one gallon of fresh water to the tank.
ConnectahosetothePumpDischargeconnectionandrouteto
a suitable drain. Plug in the pump to flush the vinegar solution
out of the pump. Pour any remaining liquid from the tank and
replace threaded caps.
5. Store the pump system in an appropriate location to prevent
damage by impact and temperature extremes.
SK2793
Typical Installation
Water heater connections may vary.
Consult appliance owner's manual for
actual connection locations.
SRS
SCALE
REMOVAL
SYSTEM
