Hitachi YUTAKI Series - DHWT- Domestic Hot Water Tank

Water pipe
installation
Service Manual
42
Accessories hydraulic installation
SMGB0066 rev.0 - 12/2009

note
Calculate and ensure that the water volume in the system is enough (see Yutaki product manual for -
recommendations).


caution
Malfunction. Damage by poor quality water. -
When it is used industrial water inside hydraulic system, it rarely causes deposits of scales or other foreign -
substances on the equipment. However, well water or river water should in most cases contain suspended
solid matter, organic matter, and scales in great quantities. Therefore, such water should be subjected to
ltration or to a softening treatment with chemicals before application as chilled water.
It is also necessary to analyse the quality of water by checking pH, electrical conductivity, ammonia ion -
content, sulphur content, and others. Should the results of the analysis be not good, the use of industrial
water would be recommended.
 

When Piping connections are performed:
Connectallpipesascloseaspossibletotheunit,sothatdisconnectioncanbeeasilyperformedwhenrequired.1.
Itisrecommendedtouseexiblejointsforthepipingofwaterinletandoutlet,sovibrationwillnotbetransmitted.2.
Wheneverpossible,sluicevalvesshouldbeinstalledforwaterpiping,inordertominimiseowresistanceandto3.
maintainsufcientwaterow.
It is recommended to apply ball valves in both water pipe connections to make easier any maintenance work.4.
Properinspectionshouldbeperformedtocheckforleakingpartsinsideandoutsidethesystem,bycompletely5.
opening the hot water inlet and outlet valves to the water condenser.
This DHWT must be fully air purged to avoid heating elements radiating the tank case without water.6.
Applythermalinsulationonthehydraulicsystempipesinordertoavoidaccidentalinjureduetoexcessiveheaton7.
piping surfaces and also to avoid heat losses.
Whentheunitisstoppedduringshutdownperiodsandtheambienttemperatureisverylow,itispossiblethatthe8.
waterinthepipesandinthecirculatingpumpfreeze,thusdamagingthepipesandthewaterpump.Inorderto
preventthis,duringshutdownperiodsitisusefultoemptythewaterfromtheinstallation.

note
Check periodically: -
Water ow and pressure -
Water leakage’s -
Fixing points tightening -
Inlet and outlet connection pipes must be 1G” -