HRV vs ERV Ventilation Systems

HRV vs ERV Ventilation Systems: What’s Best for Northland Homes?

As an electrician and installer here in Northland, I often get asked: “What’s the difference between HRV and ERV systems? Which one should I choose?” It’s a great question – and the answer depends on both the technology and our unique Northland climate.

The Basics

1. HRV (Heat Recovery Ventilation) systems bring in fresh outside air and recover heat from the stale indoor air being pushed out. They help reduce heating costs in colder climates. Cheaper, basic units.
2. ERV (Energy Recovery Ventilation) systems do the same job, but they also manage humidity – transferring some of the moisture from one air stream to the other. Balanced system.

Both systems are designed to give you fresher, healthier indoor air. 

The Plusses and Minuses

HRV Systems

✅ Strengths:

1. Works well in very cold, dry climates where heating is the main concern.
2. Simple system design.

❌ Limitations:

1. Doesn’t handle humidity well – so in damp, mild climates like Northland’s, it often doesn’t fix condensation issues.
2. Can actually make your home air too dry in winter or bring in too much humidity in summer.

ERV Systems

✅ Strengths:

1. Controls humidity as well as temperature – a big deal in Northland where we get damp winters and humid summers.
2. Helps prevent condensation on windows, mould growth, and that “musty” feeling in older homes.
3. More comfortable year-round because it balances both moisture and heat.

❌ Limitations:

1. Slightly more complex to install as a fresh air vent is ideal.

Why Expert Help Matters

We’ve seen cases where a system was installed, but the main bedroom still had condensation. When we checked, the unit was sized correctly and ducts were run well – but old window hinges were letting cold air in. Once we fixed the draught, the ERV worked perfectly.

That’s why expert installation is so important. To get the benefits, you need:

1. Correct airflow measurements – too much or too little air and the system won’t work.
2. Proper unit sizing – bigger isn’t always better; it has to match your home.
3. Smart placement of ducts and outlets – for balanced airflow.
4. Electrical safety – these are powered systems, so they need to be wired safely and to standard.

Our View for Northland

In our experience, ERV systems are the better choice for Northland homes. They deal with the humidity that HRV units struggle with, and they create a healthier, more comfortable indoor environment.

Thinking About Ventilation?

If you’re considering a ventilation system for your home, give us a call. We’ll help you decide if ERV is right for you and make sure it’s installed safely and correctly – so you actually get the results you’re paying for.

Get in touch 09 407 6468 or office@gibsonelectric.co.nz for more information.