MicroMetl is proud to celebrate more than 60 years in the HVAC industry. During that time, we’ve supported contractors, engineers, and technicians through countless equipment transitions, technological shifts, and evolving ventilation standards.
As energy recovery technology has matured, ERVs (Energy Recovery Ventilators) have become a standard solution for improving indoor air quality and reducing HVAC energy loads. Today, many early-generation ERVs are reaching the end of their service life, and the industry is entering a new phase of widespread ERV replacement.
Even though ERVs are no longer part of MicroMetl’s active manufacturing portfolio, our long-term experience with energy recovery technology gives us a clear viewpoint: ERV replacement requires more planning and evaluation than many teams expect.
The ERV Marketplace Has Changed
The first wave of ERVs installed 15–20+ years ago were typically specified by engineers to meet strict building requirements. As these systems age, contractors are increasingly asked to replace them—but often without the original specs, drawings, or ventilation criteria.
A common scenario we hear from the field:
Contractors receive only an old part number and are asked to “match it.”
This approach can lead to incorrect sizing, unnecessary cost, or poor performance. Building usage, ventilation codes, and HVAC system technologies have changed significantly since those original installations.
Before Replacing an ERV, Start With a Simple Question: What Has Changed?
Building needs evolve. Codes evolve. Occupancy patterns evolve.
Replacing an ERV with an identical unit—without assessing the current requirements—can result in oversizing, undersizing, or inefficiency.
Examples of changed conditions:
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- Former smoking rooms:
These required high air change rates. Today, most have been repurposed, and replacement ERVs may require far less ventilation.
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- Office converted to conference room:
Meeting rooms benefit from demand-controlled ventilation using CO₂ sensors rather than constant supply airflow.
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- Reduced or increased occupancy:
Occupant density affects ventilation needs dramatically.
The bottom line: Matching old specs may not reflect today’s needs—and may cost the building owner unnecessary money.
Know the CFM and Performance Goals of the Existing ERV
ERVs are rated and sold within a specific CFM range (e.g., 1000–3000 CFM at a given static pressure). But determining the actual operating CFM of an existing unit can be tricky.
Challenges you should be aware of:
- The RTU supply fan can create negative pressure, making the ERV supply fan produce more CFM than expected.
- Higher-than-intended CFM can cause the ERV supply motor to overheat and trip.
- Measuring motor amps requires opening the ERV door—which lowers static pressure and alters readings.
Without proper airflow testing, you cannot confidently determine the correct CFM for the replacement.
Additionally, each ERV is engineered for a specific:
- Heat and energy recovery percentage
- Moisture transfer capability
- Efficiency level
Knowing these values helps you ensure the new ERV aligns with current goals and expectations.
ERV Types and Options You’ll Encounter
Although MicroMetl no longer manufactures ERVs, understanding the technology is essential to making an informed replacement decision.
Two primary energy recovery designs:
- Rotating wheel ERVs
- Fixed plate/core ERVs
Each has unique strengths depending on humidity requirements, maintenance preferences, efficiency goals, and available space.
Additional considerations:
- ERV profiles and dimensions vary—curb adapters may be required
- Integration with economizers or exhaust systems may change
- Current controls may support demand ventilation, not constant supply
The market has changed significantly since first-generation ERV installations. Evaluate all available options, not just one-for-one replacements.
Seek Skilled Guidance
ERVs can appear simple on the surface, but correct selection, sizing, and integration require a deep understanding of airflow, energy recovery, code requirements, and system interaction. Replacing an ERV without proper evaluation can lead to:
- Comfort issues
- Energy waste
- Humidity problems
- Equipment stress or failure
What you should do:
- Consult with engineers or energy recovery specialists
- Review current building purpose and occupancy
- Evaluate updated ventilation codes and airflow needs
- Consider newer technologies and control strategies
MicroMetl’s Role Today
While MicroMetl is no longer manufacturing ERV products, we continue to support HVAC professionals by sharing decades of expertise in:
- Airflow management
- Curb adapters
- System integration
- Rooftop unit installation considerations
Our technical and service teams are available to help with questions related to compatibility, airflow expectations, and best practices related to the equipment surrounding an ERV installation.
Final Thought
Question assumptions. Evaluate needs. Do not replace an ERV blindly.
A properly selected and installed energy recovery system can dramatically improve comfort, efficiency, and indoor air quality. Taking the time to reassess requirements before ordering replacement equipment will ultimately save time, money, and frustration for building owners and technicians alike.
If you have questions about airflow, rooftop integration, or curb-related considerations associated with ERV replacement projects, MicroMetl is here as a knowledgeable resource.
