Bryant 50YEW Design Manual page 17

Figure 2-5: Example Secondary Heat Exchanger Sizing
Drawing 2-3 – 50YEW Typical Load Piping / No DHW Heating
or Separate DHW System / No Cooling or Separate Cooling
System: System #3 uses one or more water-to-water units
and a buffer tank for each unit. Drawing 2-3 shows a typical
piping arrangement for this system. A thermistor mounted in
an immersion well senses tank temperature, which allows the
internal controls (50YEW units only) to engage the water-to-water
unit compressor, load pump and source pump(s) when the tank
temperature drops below the set point, typically 120°F [49°C] or
less. The radiant fl oor (or baseboard, radiator, fan coil, etc.) system
therefore is completely isolated from the water-to-water unit.
The controls for the hydronic distribution system energize pumps
and/or zone valves to allow heated water in the buffer tank to fl ow
through the heating distribution system. Potable water is heated
with a separate system. If desired, cooling is accomplished with a
separate system.
Drawing 2-3: 50YEW Typical Load Piping -
No DHW Heating or Separate DHW System / No
Cooling or Separate Cooling System
Cold Water Supply
To/From
Radiant Floor,
Radiator,
Baseboard,
or Fan Coil
Heating System
H
Heating
Buffer Tank
Note 4
Bryant Geothermal Heat Pump Systems
Part II: Load Side Design / System Design & Selection
P.R.V.
Air Vent
Note 1
Exp
Tank
Note 3
HTG
C
Thermistor
Note 2
Water-to-Water System Design Guide
See drawings in section 3 for Source connections
OUT
IN
IN OUT DHW OUT IN
DHW
NOTES:
HTG
1. Place air vent at the highest point in the system. If
internal expansion tanks are installed, only an air
M
vent is required.
2. Thermistor should be installed in an immersion well.
Locate thermistor in the bottom half of the tank.
3. If DHW option is not used, DHW supply connection MUST
50YEW
be plugged.
Unit
4. If electric water heat is used instead of buffer tank, see
drawing 2-7.
5. P/T (pressure/temperature) ports are internal for
50YEW units on load and source connections.
6. Other components (additional ball valves, unions, etc.)
may be required for ease of service. This drawing
shows only minimum requirements. Your specific
Load HX Source HX
installation will dictate final component selections.
(brz plt) (coaxial)
7. Buffer tank must be approved as a heating vessel.
8. Local code supercedes any piping arrangements or
components shown on this drawing.
03Oct07
15