EP241 Hydronics, Storage, and a Single Box: Berlin Raj's Totex Vision (September 2025)

EP241 Hydronics, Storage, and a Single Box: Berlin Raj's Totex Vision (September 2025)

Author: Bill Spohn October 24, 2025 Duration: 37:26

Totex co-founder Berlin Raj joins Eric and "Overkill Bill" to unpack a single-box, hydronic monoblock system that combines space conditioning, domestic hot water, pool heating, thermal + lithium storage, EV charging integration, and backup power. Born from Berlin's lifelong tinkering (and many shocks), the idea: stop wasting condenser heat—capture it for hot water while cooling.

The system keeps all refrigerant sealed in the outdoor unit and runs PEX supply/return to indoor air handlers (ducted or ductless), avoiding field flares and refrigerant line runs. Install looks familiar—set the pad, pipe PEX, fill a glycol loop, wire power/control—yet it adds clever tricks: load matching from ~1.5–6 tons, dynamic load limiting for small panels (even ~20–30A circuits), modular thermal storage (~100 kWh cooling / ~55 kWh heating), a ~10.5 kWh lithium pack, and app/10" touchscreen controls over Modbus with hooks for BMS and home automation. In cooling-plus-hot-water mode, field tests show very high effective COP (Berlin cites "9+") because the unit harvests both sides of the cycle.

Engineered for residential and light commercial (think houses, small offices, QSRs), the unit can supply hot water up to ~165°F, support radiant/underfloor at lower temps, operate down to about -7.6°F, and be manifolded for capacity and redundancy. Texas is the target U.S. beachhead (long cooling seasons = months of "free" hot water), with pilots in Australia and U.S. pilots planned; broader availability is aimed for mid to late next year. Berlin's closing note? "People, people, people"—comfort and outcomes start with humans.

Notable Quotes:

"Why dump condenser heat when you can use it? Cool the house and make hot water at the same time." — Berlin Raj

"Dynamic load balancing means a heat pump that plays nice with a 100-amp panel." — Eric Kaiser (paraphrased)

"People, people, people. Comfort is ultimately about humans first." — Berlin Raj

 

Berlin on LinkedIn:https://www.linkedin.com/in/berlinrajm/

Totex website: https://www.totexenergy.com/

Come visit with Berin in person at the www.USHeatPumpSummit.com

 

 

This episode was recorded in September 2025.

 


Ever wonder why some buildings feel just right-healthy, comfortable, and surprisingly efficient-while others seem to work against you? That’s the territory explored in Building HVAC Science, a podcast hosted by seasoned experts Eric Kaiser and Bill Spohn. This isn't just about thermostats and ductwork; it's a deep, practical dive into the physics and principles that make indoor environments work. You’ll hear conversations that dissect real-world diagnostics, question common practices, and explain the often-overlooked science behind temperature, airflow, and moisture. The discussions naturally progress from foundational concepts to the latest tools and technologies used for measurement and verification, always linking theory to tangible results in building performance. By focusing on the interplay between proper HVAC design, installation, and human well-being, this podcast provides actionable knowledge for professionals and curious minds alike. Tune in for a clear-eyed look at how understanding the built environment leads to spaces that are better for both people and the planet.
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