Installation Manual
Applications
32│Page
Takagi
Gas Supply
Hot Water Outlet
to Fixtures
Recirculation
Pump
Ball Valves
Cold water
Inlet
Check
Valves
Expansion Tank
Unions
Hot
Water
Outlet
Air Vent
Air
Separator
S
Y-Strainer
Cold
Water
Outlet
Gas
Inlet
• Inorder to purge air in water pipes within a closed‐loop system, an air vent and air
separator should be installed in to the system.Required circulation flow rates are
labeled next to each application diagram.These flow rate requirements must be
followed.
• Toxic chemicals used in boiler
treatments such as alcohol, glycerol and glycol groups
must not be introduced into the system if the system incorporates an open‐loop
potablewatersystem.
• TheT‐H2‐DV/T‐H2‐OScanbeusedtosupplypotablewaterandspaceheatingandshall
not be connected to any heating
system or component(s) prev iously used with non‐
potablewaterwhereanychemicalswereaddedtothewater heatingappliances.
• When the system requires water for space heating at temperatures higher than
requiredforotheruses,ameanssuchasamixingvalveshallbeinstalledtotemperthe
waterfor
thoseotherusesinordertoreducescaldhazardpotential.
• Watertemperatureover125°Fcancausesevereburnsinstantlyordeathfromscalds.
• Chemicals such as diluted Glycol can be used for radiant floor, Hydro/fan coil air or
Baseboardheating only. Thedilutedsolutionof glycolmust
contain between 25% and
55% of Glycol. Be aware that in closed‐loop glycol systems, low pressure in the heat
exchangercancauselow‐temperatureboiling,resultinginexcessivenoiseanddamage
tothewaterheater.Consultwiththe
g
l
y
colmakerfors
p
ecifications
p
riortouse.
Thisisaconceptdrawingonly.
APPLICATIONS
WARNING‐Space‐Heating Applications
*Therecirculationpumpistobecontrolledby:
‐Dual‐setaquastat(recommendedw/timer)
OR
‐TakagiPumpControlsetto“Recirculation
Mode”
*Therecirculationpumpistoprovidenoless
than2GPMandnomorethan4GPMthrough
eachactivatedTakagiunitinthesystem.
‐Recirculation‐