Industrial water chillers serve two distinct roles in cannabis operations: cooling the root zone in hydroponic growing systems to optimize plant performance, and providing the low-temperature cooling needed for ethanol and solvent-based extraction processes. Both applications require precise, reliable temperature control — and the requirements are quite different.

Root Zone Cooling for Hydroponic Growing

Water temperature management is one of the most impactful variables in hydroponic cannabis cultivation. Warm nutrient solution holds less dissolved oxygen — and dissolved oxygen at the root zone is the primary driver of vigorous root growth, disease resistance, and overall plant performance.

The Dissolved Oxygen Problem

Water's ability to hold dissolved oxygen decreases as temperature rises. A nutrient solution at 75°F holds roughly 20% less dissolved oxygen than the same solution at 65°F. In a deep water culture (DWC) or recirculating hydroponic system where the reservoir is a small volume relative to the plant load, temperatures can rise quickly — especially when room temperature is high and recirculating pumps are adding heat to the solution.

High solution temperatures create a low-oxygen environment at the root zone that slows growth, weakens disease resistance, and sets the stage for root rot pathogens like Pythium.

How a Water Chiller Fixes This

A Rite-Temp water chiller circulates chilled water through a heat exchanger in the nutrient reservoir or directly through a jacketed reservoir. As the recirculating pump adds heat and ambient temperature raises solution temperature, the chiller removes that heat continuously — maintaining the nutrient solution within the target temperature range of 60–68°F regardless of room temperature or pump heat.

The result: consistently high dissolved oxygen levels, rapid root development, and a root zone environment hostile to pathogens.

Extraction Process Cooling

Cannabis and hemp extraction involves solvent-based or ethanol-based processes that require very low temperatures at various stages — particularly winterization, where extracted oil is mixed with cold ethanol and chilled to precipitate waxes, lipids, and chlorophyll.

Winterization typically requires temperatures from -20°F to -40°F. Standard process cooling chillers can't reach these temperatures — you need a low-temperature chiller with a glycol-based heat transfer fluid and a compressor and refrigerant system designed for low-temperature operation.

Rite-Temp configures chillers for extraction applications to your specific process requirements — target temperature, fluid volume, flow rate, and ambient conditions.

Sizing Your Cannabis Chiller

For root zone cooling: Calculate the total nutrient solution volume in your system, estimate the heat gain from pumps and ambient conditions, and size the chiller to remove that heat load while maintaining your target temperature. Rite-Temp's 1.5–10 ton product line covers the full range of commercial grow facility sizes.

For extraction: Your target winterization temperature, solvent volume, batch size, and batch frequency determine the required cooling capacity. Tell us these parameters and we'll size the right unit.