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Bosch Geothermal Heat Pumps
Bosch Thermotechnology Corp.
Data subject to change
Applications Manual
13 Interior Piping
Inside the home, the piping from the open-loop or closed-
loop system will be connected to the Bosch geothermal
heat pump. A typical piping layout is shown for both
applications (Fig. 103, 104). Polyethylene pipe provides
an excellent no leak piping material. Piping ttings and
elbows should be limited to prevent excessive pressure
drop.
The installer should always consult the Bosch
speci cations for piping sizes. Te on tape sealer should
be used when connecting piping to the Bosch geothermal
heat pump unit to insure against leaks and possible water-
to-refrigerant coaxial heat exchanger fouling. Never over-
tighten any connections. Flexible hoses should be used
between the Bosch geothermal heat pump unit and the
rigid system to avoid any possible vibration and should be
limited in length to 10-15 feet per run to reduce pressure
drop. Typically, 2 feet of head pressure drop is normal
for all closed-loop ground heat exchangers ttings which
include 10 to 12 elbows for inside piping to a ow center.
Closed cell insulation at least 3/8 inch wall thickness
should be used on all inside piping to avoid condensation
and possible freezing if ground loop temperatures can
fall below 50ºF. All barbed connections should be double
clamped. Ball valves should always be used and installed
in the supply and return lines for unit isolation and unit
water/ uid ow balancing. Pressure/Temperature ports
(P/T ports) are highly recommended in both the supply
and return lines for system ow balancing and waterside
diagnostics. Water ow in Gallons per Minute (GPM)
can be accurately determined and set by measuring the
water-to-refrigerant coaxial heat exchanger water side
pressure drop. The equipment speci cations will provide
information for water/ uid ow (GPM) vs. pressure drop.
