Manual 2100-537
I
Page 24 of 54
NOTE: APPLY PETROLEUM JELLY
TO O-RINGS TO PREVENT DAMAGE
AND AID IN INSERTION
WATER IN
WATER OUT
GOUND LOOP
PIPE FROM
GROUND LOOP
PIPE TO
BRASS ADAPTERS
NOTE: IF USED SUPPORT
WALL BRACKET
WITH A FIELD FABRICATED
1" FLEXIBLE HOSE
HOSE CLAMPS
FLOW METER
OPTIONAL VISUAL
STRAIGHT BARBED
PUMP MODULE
MIS-2827 A
GROUND LOOP
(EARTH COUPLED WATER LOOP APPLICATIONS)
FIGURE 7
CIRCULATION SYSTEM DESIGN
NOTE:
Unit shipped from factory with 75 PSIG low pressure
switch wired into control circuit and must be rewired to 55
PSIG low pressure switch for ground loop applications.
This unit is designed to work on earth coupled water loop
systems, however, these systems operate at entering water
(without antifreeze) temperature with pressures well below
the pressures normally experienced in water well systems.
THE CIRCULATION SYSTEM DESIGN
Equipment room piping design is based on years of
experience with earth coupled heat pump systems. The
design eliminates most causes of system failure.
The heat pump itself is rarely the cause. Most problems
occur because designers and installers forget that a ground
loop “earth coupled” heat pump system is NOT like a
household plumbing system.
Most household water systems have more than enough
water pressure either from the well pump of the municipal
water system to overcome the pressure of head loss in 1/2
inch or 3/4 inch household plumbing. A closed loop earth
coupled heat pump system, however, is separated from the
pressure of the household supply and relies on a small, low
wattage pump to circulate the water and antifreeze solution
through the earth coupling, heat pump and equipment room
components.
The small circulator keeps the operating costs of the system
to a minimum. However, the performance of the circulator
MUST be closely matched with the pressure of head loss
of the entire system in order to provide the required ow
through the heat pump. Insufcient ow through the heat
exchanger is one of the most common causes of system
failure. Proper system piping design and circulator selection
will eliminate this problem.
