What is a VFD and how does it save energy?

A Variable Frequency Drive (VFD) controls motor speed electronically rather than running at full speed constantly. Since pump and fan energy consumption follows the cube law (half speed = 1/8 energy), VFDs can reduce motor energy consumption by 30-70% for variable-load applications like HVAC systems.

Which HVAC equipment benefits from VFDs?

VFDs are most effective on equipment with variable loads: condenser water pumps, chilled water pumps, heating water pumps, cooling tower fans, make-up air unit fans, and supply/return fans. The greater the load variation, the greater the energy savings potential.

How long does VFD installation take?

Single VFD installations typically take 1-2 days including electrical work and commissioning. Multi-VFD projects for entire mechanical rooms may take 1-3 weeks depending on scope. We minimize equipment downtime by pre-staging materials and coordinating work during off-peak periods.

What is the typical payback period for VFD installation?

Payback periods typically range from 2-5 years depending on motor size, operating hours, and load profile. Utility rebates can reduce payback to 1-3 years. For 24/7 equipment like condenser water pumps, payback is often under 2 years.

VFD Installation: Smart Energy Savings

Variable Frequency Drives are one of the highest-ROI energy upgrades available for condo mechanical systems. By matching motor speed to actual demand, VFDs typically reduce pump and fan energy consumption by 30-70%.

We design and install VFD systems for pumps, fans, and cooling towers throughout your mechanical room. Our projects include proper electrical infrastructure, controls integration, and commissioning to ensure you capture the full energy savings potential.

Request Project Quote View Recent Projects

Dramatic energy savings

The cube law means small speed reductions yield huge energy savings. Running a pump at 80% speed uses only 50% of the energy. Typical savings are 30-70% on affected equipment.

Extended equipment life

Soft starts eliminate the mechanical stress of across-the-line starting. Reduced speed operation decreases bearing wear, seal stress, and vibration—extending motor and pump life significantly.

Better system control

VFDs enable precise flow and pressure control. Maintain constant differential pressure, optimize cooling tower approach, and match system capacity to actual building loads automatically.

VFD applications in condo buildings

VFDs deliver the greatest savings on equipment with variable loads. Here are the most common and effective applications in condominium mechanical systems.

Condenser Water Pumps

Highest savings potential. Match flow to actual chiller load instead of running full speed 24/7. Typical savings: 40-60%.

Cooling Tower Fans

Control approach temperature precisely. Eliminate on/off cycling that wastes energy and stresses motors.

Chilled Water Pumps

Maintain constant differential pressure across the building. Reduce flow when cooling demand is low.

Heating Water Pumps

Variable flow based on heating demand. Greatest savings during shoulder seasons with partial loads.

MAU Supply Fans

Adjust fresh air volume based on occupancy or CO2 levels. Reduce airflow during low-demand periods.

Garage Exhaust Fans

CO-based demand ventilation instead of constant operation. Major savings in underground parking garages.

The cube law: why VFDs work

Energy consumption for pumps and fans follows the affinity laws—specifically, power varies with the cube of speed. This physics creates enormous savings potential.

90% speed = 73% power: A small 10% speed reduction cuts energy use by 27%.
80% speed = 51% power: Running at 80% uses only half the energy of full speed.
70% speed = 34% power: At 70% speed, energy consumption drops to just one-third.
50% speed = 12.5% power: Half speed uses only 1/8 the energy—a 87.5% reduction.

Most HVAC systems are designed for peak load but operate at partial load most of the time. VFDs capture these savings automatically by matching speed to actual demand.

Our installation process

VFD installation requires careful planning to ensure proper sizing, electrical infrastructure, and controls integration for maximum savings.

Assessment

Motor nameplate data collection
Operating profile analysis
Electrical infrastructure review
Savings calculation
Rebate eligibility check

Engineering

VFD sizing and selection
Electrical design
Controls sequence development
BAS integration plan
Permit applications

Procurement

VFD ordering
Electrical materials
Enclosure and mounting
Rebate pre-approval
Scheduling coordination

Electrical

Disconnect installation
VFD mounting
Power wiring
Motor wiring
Grounding and shielding

Controls

BAS integration
Sensor installation
Control wiring
Sequence programming
Alarm setup

Commissioning

VFD parameter setup
Motor tuning
Control loop tuning
Performance verification
Operator training

VFD manufacturers we install

We work with leading VFD manufacturers and select equipment based on application requirements, BAS compatibility, and long-term reliability.

ABB

Industry standard

Danfoss

HVAC specialists

Yaskawa

Premium drives

Schneider

Altivar series

Siemens

Building integration

Eaton

PowerXL series

Allen-Bradley

PowerFlex series

Toshiba

HVAC optimized

Selection criteria: We match VFD selection to your specific application considering motor characteristics, control requirements, BAS protocol compatibility (BACnet, Modbus, etc.), harmonic mitigation needs, and long-term parts availability.

Compliance & technical considerations

VFD installations involve electrical work and controls integration requiring proper planning and execution.

Electrical Code

All work by licensed electricians per Ontario Electrical Safety Code. Proper permits, ESA inspection, and documentation. Panel capacity verified before installation.

Harmonic Mitigation

VFDs can generate harmonics that affect power quality. We specify line reactors, DC chokes, or active filters as needed to meet IEEE 519 recommendations.

BAS Integration

Proper integration with building automation enables remote monitoring, trending, and optimization. We configure communication protocols and verify data exchange.

For property managers & boards

VFD installations offer one of the best returns on investment for building energy upgrades. The math is compelling—significant savings with relatively modest capital investment.

Strong ROI: Typical payback periods of 2-5 years, often reduced to 1-3 years with utility rebates. After payback, savings flow directly to the operating budget.
Utility rebates: Most utility incentive programs offer significant rebates for VFD installations. We identify and apply for all applicable programs.
Reserve fund friendly: VFD projects can often be funded from operating budgets due to quick payback, avoiding reserve fund impact.
Measurable results: Energy savings are easily verified through utility bills. We provide before/after analysis to demonstrate ROI.

VFD Projects Across Toronto

We've completed VFD installations in buildings across the GTA—from single-pump retrofits to complete mechanical room modernizations. See our project portfolio for examples.

View Projects

FAQs

A Variable Frequency Drive (VFD) is an electronic device that controls motor speed by varying the frequency of electrical power supplied to the motor. Instead of running at full speed constantly (which is how most older systems operate), a VFD adjusts speed to match actual demand. The energy savings come from the cube law: power consumption varies with the cube of speed. Running a motor at 80% speed uses only 51% of the energy; at 50% speed, only 12.5%. For variable-load HVAC applications, this typically translates to 30-70% energy savings.

Prioritize equipment with the highest operating hours and most variable loads. Condenser water pumps are often the best candidates—they run 24/7 during cooling season but rarely need full flow. Cooling tower fans, chilled water pumps, and garage exhaust fans are also excellent candidates. We analyze your specific equipment and load profiles to identify the highest-ROI opportunities.

Payback periods typically range from 2-5 years depending on motor size, operating hours, and load variability. Equipment running 24/7 (like condenser water pumps) often achieves payback under 2 years. Utility rebates can significantly improve payback—sometimes cutting it in half. We provide detailed ROI calculations during the proposal phase based on your specific equipment and operating conditions.

Most standard induction motors work well with VFDs. However, older motors may run warmer due to harmonic heating, and some may need bearing protection. We evaluate motor condition and compatibility during assessment. In some cases, we recommend motor replacement alongside VFD installation—premium efficiency motors combined with VFDs maximize total savings.

Yes, most utility incentive programs offer substantial rebates for VFD installations since they deliver proven, measurable energy savings. Rebates are typically calculated based on motor horsepower and estimated savings. We identify applicable programs during assessment and handle rebate applications as part of our project scope—ensuring you capture all available incentives.

Costs depend on motor size, electrical infrastructure requirements, and controls integration complexity. Typical per-VFD costs range from $5,000-15,000 for common HVAC motor sizes (5-50 HP), including equipment, installation, and commissioning. Larger motors or complex installations cost more. After utility rebates, net costs are often 30-50% lower. We provide detailed proposals with ROI calculations to help evaluate the investment.

Ready to reduce your energy costs?

Request a VFD assessment to identify your highest-ROI opportunities. We'll analyze your equipment, calculate potential savings, and provide a detailed proposal including available rebates.

Request Assessment

Hudson HVAC Secures The Well Toronto