Refrigerant Undercharge Detection

30% Energy Waste Identified & Corrected via Continuous Monitoring

Mitsubishi MXZ-SM36NAMHZ  ·  Colorado Deployment  ·  February 2026

Undercharge

• 40% refrigerant deficit
• Efficiency Gain: ~30% energy intensity reduction
• Annual Waste: 2,400 kWh ($360/yr at $0.15/kWh)
• CO₂ Avoided: 1.26 MT CO₂/yr (eGRID RMPA)

The Situation

A Fault That Would Have Gone Undetected Indefinitely

Thalo's continuous cellular monitoring detected anomalous power draw on a Mitsubishi MXZ-SM36NAMHZ VRF heat pump at a Colorado residential deployment. The system flagged abnormal energy consumption patterns before any tenant complaint or visible failure occurred.

Field inspection confirmed a 40% refrigerant undercharge. Without telemetry, this fault would have continued undetected — silently wasting energy and stressing the compressor. Field surveys find 78% of installed systems have charge issues.

The Findings

Key Results After Correction

• Energy intensity reduced from 1.59 → 1.11 kWh/°F-day (~30%)
• Monthly winter savings of ~480 kWh ($72/mo)
• Avoided emissions of ~1.26 MT CO₂/yr (≈ 3,200 mi driving)

This fault would have gone undetected indefinitely without telemetry. Field surveys find 78% of installed systems have charge issues.

Methodology

Temperature-Normalized Energy Analysis

Daily kWh was normalized by heating degree-days (base 65°F). Before/after compared via OLS regression with R² goodness-of-fit. Recovery transient (Jan 30–31) excluded. Emissions use EPA eGRID RMPA factor: 1,159 lbs CO₂/MWh.

Colorado's RMPA grid (1,159 lbs CO₂/MWh) is 43% more carbon-intensive than the national average — making every kWh saved here carry outsized climate impact.

Fleet-Scale Impact

What This Means Across 24,000 Units

Assuming 25% of units have charge faults at half this severity: ~7.2M kWh/yr wasted, ~$1.1M/yr excess electricity, and ~3,790 MT CO₂/yr of avoidable emissions — all detectable and correctable through continuous monitoring.

Temperature-Normalized Energy: Before vs. After Service

Each point = one day's energy use vs. heating degree-days (base 65°F). Red = undercharged; Green = corrected.

Mitsubishi MXZ-SM36NAMHZ · Colorado Deployment

Measured Impact

• Energy intensity (before): 1.59 kWh/°F-day
• Energy intensity (after): 1.11 kWh/°F-day
• Monthly winter savings: ~480 kWh ($72/mo)
• Annual energy waste corrected: ~2,400 kWh
• CO₂ avoided per year: 1.26 MT

Ready to Generate Results Like These?

Book a 15-minute demo and see live HVAC Copilot data from real deployments. We'll walk through how it applies to your operation.