The Sentinel R600 Air Source Heat Pump Thermal Fluid (MPN R600L-20L-DRUM) is a ready-to-use, propylene glycol-based inhibited antifreeze formulated specifically for air source heat pump (ASHP) circuits and external pipework. Supplied in a 20 litre drum, it delivers combined frost, limescale, and corrosion protection in a single fill, and is designed to provide permanent protection for the life of the system provided minimum concentration levels are maintained.
-10°C (1 Drum)
Frost Protection
-30°C (2 Drums)
Frost Protection
Propylene Glycol
Base Chemistry
Dilution Guidance
One 20L drum of Sentinel R600 combined with 80 litres of water in a typical 100 litre ASHP system provides the minimum concentration of corrosion and scale inhibitor along with frost protection to approximately -10°C. Two 20L drums provide protection down to approximately -30°C.
System Volume Matters
The dosage above assumes a typical 100 litre ASHP system volume. Where system volume is unknown or differs significantly from this, frost protection level should be verified using a Sentinel FrostCheck Test Kit rather than assumed from drum count alone.
Pre-Fill Preparation Required
New systems and those up to 6 months old should be cleaned and flushed with Sentinel X300 before filling with R600. Existing systems should be cleaned with Sentinel X400 or Sentinel X800 first. All entrained air must be removed from the system before operation.
Dual-Purpose Protection
Combines frost protection down to -10°C or lower (depending on dosage) with corrosion and scale inhibition in a single ready-to-use fluid, avoiding the need for separate antifreeze and inhibitor products.
No Dilution Required
Supplied ready to use with no dilution needed before adding to the system, simplifying commissioning on site.
Non-Toxic Formulation
Based on propylene glycol, which is non-toxic and biodegradable, making it a safer choice than ethylene glycol-based alternatives for systems near living spaces.
Permanent Protection
Resists degradation to extend fluid life; if minimum concentration levels are maintained, the product does not need to be replaced over the life of the system.
Multi-Metal Compatibility
Provides effective corrosion and scale protection for system metals commonly found in ASHP circuits, extending component lifespan.
Verifiable Protection Level
Frost protection achieved after dosing can be checked directly using the Sentinel FrostCheck Test Kit, giving installers a documented, testable result rather than an assumption.
| Product Identity |
| Manufacturer |
Sentinel (Sentinel Performance Solutions) |
| Product Name |
Sentinel R600 Thermal Fluid |
| MPN |
R600L-20L-DRUM |
| Range |
Sentinel R Range - Air Source Heat Pump Solutions |
| Performance |
| Frost Protection (1 x 20L drum, ~100L system) |
Approx. -10°C |
| Frost Protection (2 x 20L drums) |
Approx. -30°C |
| Working Pressure |
1-3 bar |
| Chemistry |
Propylene glycol-based inhibited antifreeze |
| Colour |
Blue |
| Physical Specification |
| Capacity |
20 L |
| Length |
280mm |
| Width |
248mm |
| Height |
380mm |
| Diameter |
290mm |
| Format |
Liquid, ready to use |
| Compatibility & Standards |
| Suitable For |
Air source heat pump circuits and external pipework |
| Compatible Systems |
All materials commonly found in typical ASHP circuits, including aluminium components |
| Water Suitability |
Hard and soft water |
| Quality System |
Manufactured to ISO 9001 |
How much frost protection does one drum provide?
One 20L pail of Sentinel R600 added to a typical 100 litre ASHP system provides frost protection to approximately -10°C. Using two 20L drums extends protection to approximately -30°C.
Do I need to dilute this product before use?
No. Sentinel R600 is supplied ready to use and requires no dilution before adding to the heat pump circuit.
Does R600 also protect against corrosion and scale, or just frost?
Both. It's a multipurpose inhibited antifreeze that provides corrosion and scale protection for system metals in addition to frost protection down to its rated setting point.
How do I check the frost protection level after filling?
Use a Sentinel FrostCheck Test Kit to verify the actual protection level achieved, particularly important where system volume is uncertain.
Do I need to clean the system before filling with R600?
Yes. New systems and those up to 6 months old should be cleaned and flushed with Sentinel X300; existing systems should be cleaned with Sentinel X400 or Sentinel X800 before filling.
Does this product need replacing periodically?
No, provided minimum concentration levels are maintained, Sentinel R600 is designed to provide permanent protection without needing replacement.
