9 expert tips for correct glycol use

9 EXPERT TIPS FOR CORRECT GLYCOL USE

1. maintain the chiller and chiller system's hygiene and fluid

The chilled water system and fluid used are the most important aspects to an installation.
The water/glycol is the vehicle which collects the heat from the process and delivers it to the
chiller, and the pipework is the road along which the fluid must travel. If either of these two
are deficient in any way, the chiller’s operation will be compromised and the heat transfer
capability will be reduced.


If necessary, filters/strainers should be installed and checked regularly, although the best
policy is to tackle the source of any contamination. The chilled water system must be flushed,
cleaned and sanitised prior to adding a new water/glycol solution. It must also be regularly
sampled and tested to ensure there are no underlying or progressive contamination and/or
corrosion issues.


For new, or recently cleaned and dosed systems, we recommend a test after three months of
operation, including a comprehensive sample analysis. Thereafter, we recommend six
monthly routine tests, along with regular visual examinations to check for colour and
suspension.


Six monthly analysis is offered free of charge when Glycol has been supplied by Intelicare.
Based on these results a quotation will be supplied for any remedial work recommended.

2. consider Ethylene glycol in process/industrial applications

Ethylene-based glycol is the standard process/industrial antifreeze additive and can be used
in any application where low toxicity is not a requirement. In terms of efficiency losses,
ethylene glycol has the least effect on flow rate, heat transfer capability, and pressure loss.
However, ethylene glycol has moderate acute oral toxicity so should not be used in
applications where it may encounter potable water, food and/or beverage processing.


CoolFlow IGE has been especially formulated from Ethylene Glycol for use as an Industrial
Grade Secondary Refrigerant Antifreeze for use in Process Cooling, Refrigeration and Air
Conditioning systems, where toxicity is not an issue.

3. consider Propylene-based glycol for food and beverage applications

Propylene-based glycols have low toxicity and are the ideal antifreeze additives for
applications in the food and beverage industry and where user contact is a frequent
occurrence. For extra reassurance, make sure it has been tested by the National Sanitary
Foundation, which is shown by a NSF mark. This is the assurance that the product is
approved by an independent certification organisation that is valued by consumers,
manufacturers, retailers, and regulatory agencies worldwide.

4. use the correct water

Most systems use ordinary mains ‘tap’ water, and while good for human consumption, it can
be quite damaging to any chiller and its associated machinery and systems. The relative
hardness (and hence the mineral content) varies from region to region, so applying the
appropriate inhibitors and biocide is of vital importance. Even microbiological contaminants
vary, giving a degree of unpredictability to using town mains water or any other uninhibited
water source. Using a ‘pure’ water – distilled, demineralised, de-ionised or RO water – will
remove this unpredictability.


However, on its own, pure water can be damaging to heat exchangers due to its tendency to
attack certain metals within the chiller and water circuit. It also has very low conductivity
which can be a problem with some chillers and systems. We recommend the use of pure
water with a suitable (minimum 20%) inhibited glycol mix to give the ultimate system
protection. The added glycol will increase the solution’s conductivity to a level which is
compatible with both the system materials and any conductivity-based instrumentation.
It is important to never use continuously de-ionised/polished water or any pure water
without inhibited glycol.

5. never use automotive antifreeze

Automotive antifreeze is formulated for engine cooling rather than process or industrial cooling applications, so when it is used for the wrong applications, it can cause problems with flow rates/pressures and reduced heat transfer. Many automotive antifreeze products are not glycol-based and contain other alcohols or glycerine, as well as silicate-based inhibitors, which can coat heat exchangers, attack pump seals, and form a gel, significantly affecting flow rates.


CoolFlow IGE is miscible with water in all proportions and can protect RAC systems down to -50°C depending on concentration. CoolFlow IGE exhibits super-cooling characteristics and mixtures containing in excess of 55% by volume do not freeze solid, alleviating any concern over possible expansion and burst damage.

6. be aware of the effects of antifreeze on a system

Plain water is one of the most efficient pumped fluids for absorbing and carrying heat.
However, when any other chemical is added to it, this ability is affected. Adding glycol will
cause an increase in the fluid’s viscosity and density, and decrease its heat transfer and heat
carrying properties.

These property changes will not affect the overall functionality of your
chilling plant and system as long as they are understood and discussed beforehand as they
will result in a slightly reduced cooling capacity, an increased pumping power consumption
and an increased fluid temperature difference (or an increased fluid flow).


Optimum Flow: CoolFlow IGE has improved heat transfer characteristics, including lower
Dynamic Viscosity and higher Thermal Conductivity. For detailed comparison please refer to
the Fluid Performance Chart - available upon request.

7. check the rules

Some areas have regulations regarding the use and disposal of particular glycols and
antifreeze solutions, concerning things such as ground structure, the water table and
drainage. Be sure to consult your local authority to check the local environmental rules.
Businesses should also consider using a bio-glycol as an environmentally-friendly solution.
Bio-glycols are derived from a sustainable source and are non-toxic, non-flammable, nonhazardous,
and biodegradable.


Biodegradable: CoolFlow IGE mixtures are readily biodegradable (90% over ten days) and
will not remain in the environment or bio-accumulate.

8. never mix your glycols!

Different types and brands of glycol shouldn’t be mixed. Most modern glycols contain inhibitors and are dyed for identification. If they are accidentally mixed, incompatibilities can lead to separation and/or reaction, resulting in gel formation which will clog filters, strainers, and pump suctions, as well as causing a deterioration in heat carrying and transfer properties.

9. only use inhibited glycol

Uninhibited glycol and water mixtures are very corrosive, often even more than standard mains water. Modern process and industrial glycols contain inhibitors alongside a pH buffer and biocide to protect against corrosion, scale formation, and rust. For a system to be contamination-free, it needs to be properly flushed, cleaned and sanitised before the addition of a suitable inhibited glycol and water mixture.


Protection: CoolFlow IGE contains synergistic corrosion inhibitors to protect metals commonly found in such systems. It has been tested in accordance with BS5117 and found to meet BS6580 and ASTM D1384 corrosion standards.

CONTACT US

InteliCare Limited
Bottom Woodbeck Farm
Retford
Nottinghamshire
DN22 0PB

Registered in England and Wales

Company registered number: 05699947

email: sales@intelicare.co.uk
tel: +44 (0)1777 248777
fax: +44 (0)1777 248777

ABOUT US

Intelicare is the trusted UK partner of leading European suppliers of thermoplastics handling, heating and cooling technology, heated platen presses, industrial ovens and resin dispensing.

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