ThermaFlow VT3 Physical Properties


1.02 - 1.26 g/cm³


7.5 - 10.5 depending on inhibitors

Boiling Point:



a clear, slightly viscous liquid. It is slightly sweet to the taste and has a non-pungent but characteristic aroma.

Available in:

5, 10, 15, 20, 25, 205 & 1000 litre containers and bulk tankers.


For a quote or assistance

Tel: (021) 385 0908

Ecologically and Environmentally Friendly Non-Toxic Heat Transfer Fluid with Antifreeze for use in Hot Water Heating Systems. Based on Refined Vegetable Extracts and BS6580 & ASTM D1384 high temperature rated Corrosion, Scale and Biological Inhibitors.

ThermaFlow VT3 has been especially formulated to provide plumbing and heating engineers with a heat transfer fluid that is 100% RENEWABLE. I.E. not derived from non-renewable crude oil. ThermaFlow VT3 is based on sustainable Refined Vegetable Extracts that are Non-Toxic, Bio-Degradable and more thermally efficient than Propylene Glycol based coolants. Subsequently ThermaFlow VT3 could be considered the most ecologically friendly antifreeze available.

Antifreeze AntiFreeze

ThermaFlow VT3 is miscible with water in all proportions and can protect Hot Water Heating Systems down to -50°C depending on concentration.

ThermaFlow VT3 exhibits super-cooling characteristics and mixtures containing in excess of 50% by volume do not freeze solid, alleviating any concern over possible expansion and burst damage.

non toxic Non-Toxic

ThermaFlow VT3 has an LD50 toxicity rating (Oral Rat) of ≥15,000 mg/kg of body weight (bw) = “Relatively Harmless”. As confirmed by the Hodge & Sterner Scale.

Renewable Renewable

Manufactured using a blend of refined vegetable extracts. I.E. they do not contain any crude oil derived or synthetic constituents

Corrosion control Corrosion Control

ThermaFlow VT3 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.

ThermaFlow VT3 also contains scale and biological inhibitors to help prevent fouling – thus promoting long operational life and high thermal efficiency.

Biodegradable Biodegradable

ThermaFlow VT3 mixtures are readily biodegradable (90% over ten days) and will not remain in the environment or bio-accumulate.

Quality Assured Quality Assured

All Hydratech products are manufactured in accordance with certified ISO9001-2008 procedures


As per BSRIA guide BG 29/2012 all pipe-work systems should be clean and free from biological contamination prior to commissioning.

To minimise corrosion air ingress should be minimised. A pressurised system is best.

Determine the total system volume and add ThermaFlow  VT3 to the system according to the minimum operating temperature required (see table, below). The minimum dose of ThermaFlow VT3 should not be less than 25% of the system volume and the maximum does not normally exceed 60%. We recommend the use of deionised, distilled or UltraPure™ water for this dilution. Avoid water containing high levels of calcium salts or Chlorides [Cl-].

Health & Safety: Please refer to the associated Safety Data Sheet - Available via Login or upon request.

Shelf Life: 3 years when stored in sealed containers out of direct sunlight.

Available in: 5, 10, 15, 20, 25, 205 & 1000 litre containers and bulk tankers.

ThermaFlow VT3 can also be supplied as a Ready-To-Use solution.

Mixing Guide

Frost Protection °C v/v of ThermaFlow VT3 Refractive Index
-10 25% 1.356
-15 33% 1.364
-20 39% 1.370
-25 44% 1.373
-30 48% 1.380
-35 52.5% 1.383

When measuring the percentage of ThermaFlow VT3 in the system use a refractometer

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