15
Water system
balancing
A complete knowledge of the
hydronic system, including its
components and controls, is
essential to proper water system
balancing and should only be
completed by a qualified expert. The
system must be complete, and all
components must be in operating
condition before beginning the water
system balancing procedures.
Each hydronic system has different
operating conditions depending on
the devices and controls installed for
the particular application. The actual
balancing technique may vary from
one system to another.
After the proper system operation
is established, the appropriate
operating conditions such as
water temperatures, flow rates and
pressure drops should be recorded
for future reference.
Before and during water system
balancing, conditions may exist due
to incorrect system pressures which
may result in noticeable water noise
or undesired valve operation. After
the entire system is balanced, these
conditions will not exist on properly
designed systems. If any of these
conditions persist, recheck the
system for air that may not have been
properly vented during start-up.
Water treatment
Proper water treatment is
a specialized industry and
therefore it is recommended
to consult an expert in this
field to analyze the water for
compliance with the water
quality parameters listed below
and to specify the appropriate
water treatment program. The
expert may recommend rust
inhibitors, scaling preventative,
antimicrobial growth agents or
algae preventatives. Anti-freeze
solutions, glycols, may also be
used to lower the freezing point.
Water content
Required concentration
Sulphate
< 200 ppm
pH
7.0 – 8.5
Chlorides
< 200 ppm
Nitrate
< 100 ppm
Iron
< 4.5 mg/L
Ammonia
< 2.0 mg/L
Manganese
< 0.1 mg/L
Dissolved solids
< 1000 mg/L
Calcium carbonate hardness
300 – 500 ppm
Calcium carbonate alkalinity
300 – 500 ppm
Particulate quantity
< 10 ppm
Particulate size
800 micron max
All Zehnder Rittling water coils
are constructed of copper tubes
and brass headers. It is the end
user’s responsibility to ensure
that any of the water delivery
components are compatible with
the treated water.
Failure to provide proper water
quality will void the fan coil unit’s
warranty.
Water system balancing and treatment
