Knowledge: Product profile
Market liquidity
John Westerman, Climalife, gives the lowdown on best practice for thermal
transfer fluids and their natural alternatives
hermal transfer fluid is known
under many guises; glycol, heat
transfer fluid and sometimes
antifreeze. It has long been
regarded by some environmental
engineering professionals as a commodity
product; however, its use has seen significant
growth over the last 10 to 15 years throughout
renewable heating applications.
As its name suggests the thermal transfer
fluid performs the function of transferring
thermal energy from one location to another.
It may be one of the least expensive
components of a system but it is critical to
the way it functions and how effectively it
transfers warmth and provides protection
from freezing and corrosion. If sourced or used
incorrectly, it can in the long term prove to be
a very expensive short cut!
These fluids have the flexibility of use
across a whole range of applications from
solar thermal, heat pumps, underfloor heating
and district heating.
Some of these applications only use
water as their thermal transfer fluid, however
whilst water is cheap, freely available and
has very good thermal capacity, its freezing
point is a problem. The benefit of using a high
quality heat transfer fluid is that they contain
corrosion inhibitors which can help to limit
corrosion in water systems and thus prolong
the life of the system.
Coming to market are many good quality
natural alternative thermal transfer products
with plenty of expertise to support them.
They can often deliver similar performance
capability to more traditional products
but carry with them added environmental
benefits.
One example of a natural alternative on
the market is Greenway Neo from Climalife.
Greenway Neo is a heat transfer fluid based
on 1,3 Propanediol (Bio-PDO) which is a
raw material produced by fermentation of
natural 99.7 percent purified glucose syrup. It
can be a reliable and effective alternative to
T
Climalife’s organically-based inhibitor vs traditional mineral-based inhibitor
traditional MPG-based fluids developed from
the petrochemical industry.
Products such as Greenway Neo
are thought to have far less impact on
climate change, virtually no impact on the
deterioration of the ozone layer and support
a shift in reliance on fossil fuels offering a
cleaner production process. These products
can offer similar features and benefits to their
more traditional counterparts and are another
good way to support the government’s aims
for organisations to reduce their carbon
footprint.
To ensure a system is working at its
optimal energy efficiency, ensure longevity
and trouble free operation, preparation and
maintenance are absolutely key. Some things
to consider: 3. Ensure the system is clean, free of dirt,
grime, rust and other particles and does
not have stagnant water in it.
4. Test for leaks before filling, charge slowly
to avoid air pockets and purge any
entrapped air.
5. Label the system as to the concentration
and type of fluid used.
6. If diluting a thermal transfer fluid yourself,
it’s recommended that demineralised or
de-ionised water is used. Tap water is
chlorinated and hard water can contain
minerals which cause scale or sludge
that can be detrimental to the longevity
of the system.
1. The system is correctly sized and
material compatibility exists for all the
components used, eg pumps, pipework,
joints and seals. 7. 2. The correct dilution for the frost
protection required and the density/
viscosity of that concentration is
considered when selecting the correct
pump size for the desired operating
temperatures (when these fluids get
close to their freezing point, viscosity
will increase and make them harder to
pump). A regular annual check is recommended
to make sure the fluid is in good
condition, hasn’t deteriorated and will
give freezing protection to the level
required. It can also be an early warning
indicator, if there are rust particles or
sludge present.
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