Coolant concentrate that protects the engine against freezing, overheating and corrosion – mixed in a ratio tailored to the climate and application.
HEPU® P999-LL18 Coolant Concentrate (BMW LC-18, Green)
HEPU® P999-LL18 is part of the P999 series of HEPU® coolant concentrates for modern cooling systems, from passenger cars to heavy-duty vehicles. Supplied undiluted, it lets the workshop prepare exactly the right mixing ratio for the climate and application, with year-round protection against freezing, overheating and corrosion.
P999-LL18 is the green, long-life concentrate of the series, based on a hybrid Si-OAT technology. It is recommended for use according to the BMW Lifetime Coolant LC-18 / Frostox HT-12 specification, for filled-for-life use in the engine and cooling system. Mixed 1:1 with demineralised water it protects down to −38 °C.
Key features
Benefits
| Parameter | Value |
|---|---|
| Product type | Coolant / antifreeze — hybrid Si-OAT full concentrate (long-life) |
| Base | Ethylene glycol (ethanediol) 80–95 % |
| Inhibitor | Hybrid Si-OAT (organic acid + silicate additive package) |
| Colour | Green |
| Odour | Characteristic |
| Density at 20 °C | 1.12 g/cm³ |
| pH at 20 °C | ~8.7 |
| Freezing point (concentrate) | Not determined |
| Boiling point | 197 °C |
| Frost protection (1:1 with water) | down to −38 °C |
| Flash point | 111 °C |
| Auto-ignition temperature | 398 °C |
| Flammability | Non-flammable |
| Vapour pressure at 25 °C | 0.1 hPa |
| Solubility in water | Miscible |
| Free of | Borate, nitrite, amine, phosphate |
| Application | Engine coolant (mix with water before use) |
HEPU® P999-LL18 is a concentrate and must be mixed with clean water before filling the cooling system.
Method
Mixing ratio → frost protection
| Concentrate : Water | Frost protection |
|---|---|
| 50 : 50 | −38 °C (verified HEPU figure) |
| ~40 : 60 | ~ −25 °C (approx.) |
| ~60 : 40 | ~ −52 °C (approx.) |
Guidance: keep the concentrate content between 33 % (minimum, for year-round corrosion protection) and 60 % (practical maximum). Higher glycol content does not improve frost protection and reduces heat transfer.
HEPU® P999-LL18 is recommended for use according to the following specifications and standards:
Always confirm the coolant type and colour required by the vehicle manufacturer before topping up or mixing with another product.
SAFETY WARNINGS
Hazard-determining components of labelling:
ethanediol
Hazard statements
Precautionary statements
Full details in the Safety Data Sheet (SDS), available for download.
MANUFACTURER AND ENTITY RESPONSIBLE FOR PLACING THE PRODUCT ON THE MARKET
HEPU® Autoteile GmbH
Am Kreuzweg 2, 32689 Kalletal-Hohenhausen
Germany
Safety data sheet / Sicherheitsdatenblatt
Other files / Andere Dateien
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HEPU® Coolant Catalogue
Discover the complete range of HEPU® coolants and coolant concentrates in one catalogue. From high-quality coolant concentrates (P999 series) and ready-to-use coolants (P900 / P888) to windscreen washer fluid, windscreen de-icer and AdBlue – all developed without the addition of nitrites and phosphates and compliant with the specifications of individual vehicle manufacturers.
