C L I M AT E M A S T E R WAT E R - S O U R C E H E AT P U M P S
Tranquility
®
Large Water-to-Water (TMW) Series
R e v. : O c t o b e r 5 , 2 0 2 1
C l i m a t e M a s t e r Wa t e r-S o u rc e H e a t P u m p s
12
Ground-Water Heat Pump Applications
Expansion Tank and Pump -
Use a closed, bladder-
type expansion tank to minimize mineral formation due
to air exposure. The expansion tank should be sized
to handle at least one minute run time of the pump to
prevent premature pump failure using its drawdown
capacity rating. Discharge water from the unit is not
contaminated in any manner and can be disposed of
in various ways depending on local building codes; i.e.
recharge well, storm sewer, drain field, adjacent stream
or pond, etc. Most local codes forbid the use of sanitary
sewer for disposal. Consult your local building and zoning
department to assure compliance in your area.
Water Control Valve -
Note the placement of the water
control valve. Always maintain water pressure in the heat
exchanger by placing water control valves at the outlet
of the unit to prevent mineral precipitation. Slow opening
and closing valves are recommended to reduce water
hammer. If water hammer persists, a mini-expansion
tank can be mounted on the piping to help absorb the
excess hammer shock. Ensure that the total ‘VA’ draw
of any field-supplied valve can be supplied by the unit
transformer.
Flow Regulation -
Flow regulation can be accomplished
by two methods. First, most water control valves have
a built in flow adjustment. By measuring the pressure
drop through the unit heat exchanger, flow rate can be
determined and compared to Table 2. Since the pressure
is constantly varying, two pressure gauges might be
needed. Simply adjust the water control valve until
the desired flow of 1.5 to 2 gpm per ton is achieved.
Secondly, a flow control device may be installed. The
devices are typically an orifice of plastic material that
is designed to allow a specified flow rate. These are
mounted on the outlet of the water control valve. On
occasion, these valves can produce a velocity noise that
can be reduced by applying some back pressure. This
is accomplished by slightly closing the leaving isolation
valve of the well water setup.
Shut off valves should be included for ease of servicing.
Unit has internal flush valves to allow alkaline flushing
of just the heat exchanger. Pressure temperature plugs
should be used so that flow and temperature can be
measured. Supply and return water piping materials should
be limited to copper, PE, or similar material. PVC or CPVC
should never be used as they are incompatible with the
POE and PVE oils used in HFC-410A products and piping
system failure and property damage may result.
Table 1
In areas with extremely hard water, the owner should
be informed that the intermediate heat exchanger may
require occasional flushing. Use a 2% phosphoric or
sulfamic acid solution, on the unit side and manufacturer’s
recommendation on ground water side.
Model
Flow GPM
Pressure Drop
PSI (FT)
TMW360
45
1.2 (2.7)
68
2.4 (5.6)
90
4.2 (9.6)
TMW600
75
1.7 (3.9)
113
3.6 (8.3)
150
6.3 (14.5)
TMW840
105
2.7 (6.2)
158
6.0 (13.7)
210
10.4 (23.7)
WARNING!
Polyolester Oil, commonly known as POE oil, or
Polyvinylether, commonly known as PVE oil, are synthetic
oils used in many refrigeration systems including those with
HFC-410A refrigerant. POE, or PVE oil, if it ever comes in
contact with PVC or CPVS piping, may cause failure of the
PVC/CPVC. PVC/CPVC piping should never be used as
supply or return water piping with water source heat pump
products containing HFC-410A as system failures and
property damage may result.
⚠
WARNING!
⚠
Water quantity should be plentiful and of good quality.
Consult Table 3 for water quality guidelines. The unit has
stainless steel braze plate heat exchangers. In ground
water situations where scaling could be heavy or where
biological growth such as iron bacteria will be present, a
closed loop system is recommended. It is mandatory to
install an intermediate heat exchanger to isolate an open
loop from the heat pump loop on open well systems. Heat
exchangers may over time lose heat exchange capabilities
due to a build up of mineral deposits inside. These can be
cleaned only by a qualified service mechanic as acid and
special pumping equipment are required.
