ERV vs HRV
An ERV also moves water vapor. An HRV moves heat only.
Tested and reviewed by Jonathan West · Updated October 20, 2026 ·how we research these
ERVs and HRVs are both balanced ventilators with a heat exchanger, one or more fans and controls. Both give a home a controlled way to ventilate while minimizing energy loss. The difference is in what each one recovers.
The sections below cover that difference, the points the cited sources leave unpublished, and the questions to bring to a heating, ventilation and air conditioning (HVAC) contractor. At DIY Repair Guide, we compiled it from the US Department of Energy (DOE) Building Science Education Support Center and its Building America ventilation guide.
ERV or HRV in One Minute
The difference between an ERV and an HRV is moisture. An ERV transfers some water vapor between the airstreams, which helps indoor humidity stay more constant. An HRV recovers heat only.
Both types include a heat exchanger, one or more fans that move air through the unit, and controls. In winter, both move heat from indoor exhaust air to colder incoming outdoor air, which lowers heating costs. In summer, the cooler indoor air cools the warmer incoming air, which lowers cooling costs.
Pick an ERV if the goal is indoor humidity that stays more constant. Pick an HRV if the goal is heat recovery alone, since the sources describe it recovering sensible heat only. The sources do not rank one type above the other.
What Both Units Share
Both an ERV and an HRV contain three parts: a heat exchanger, one or more fans that move air through the unit, and controls. The fans move air through the unit, and the heat exchanger is where heat passes between the outgoing indoor air and the incoming outdoor air. The cited sources name the controls but do not describe them.
The DOE whole-house ventilation page lists four whole-house ventilation types: exhaust, supply, balanced, and energy recovery. Balanced ventilation moves equal volumes of outside air in and inside air out. The same material says balanced heat recovery ventilation dilutes contaminants and also recovers heat.
Many homes lack whole-house fresh air systems, so moisture, dust, pollen and particulates can build up. The sources say that buildup can trigger asthma and allergy attacks and other health problems.
What an HRV Recovers
An HRV recovers sensible heat only, and the Building America guide defines it that way. The sources do not say an HRV transfers moisture.
In winter, an HRV moves heat from indoor exhaust air to colder incoming outdoor air, which lowers heating costs. In summer, the cooler indoor air cools the warmer incoming air, which lowers cooling costs. The sources give no dollar figure for either saving.
The sources do not describe an HRV changing indoor humidity. If heat recovery is the only goal, the HRV matches that goal on the points the sources cover.
What an ERV Recovers
An ERV recovers both latent heat, which is the moisture part of the air, and sensible heat. The Building America guide defines the ERV that way.
In addition to exchanging heat, an ERV transfers a certain amount of water vapor, which helps indoor humidity stay more constant. The sources do not give the amount of vapor an ERV transfers, and they do not give a figure for any model.
The sources describe the same winter and summer heat movement for an ERV as for an HRV. The moisture transfer is the added item that separates the two types on the points the sources cover.
Where Local Exhaust Fans Fit
Kitchen and bathroom exhaust fans are local exhaust, and the sources say they run intermittently.
Whole-house mechanical ventilation is a separate category, and the sources say it is still needed in energy-efficient homes.
The sources do not say whether a whole-house ERV or HRV replaces the kitchen and bathroom fans. Ask the contractor how the design handles them.
Sensible Effectiveness Range
The Building America guide puts the sensible effectiveness of ERV and HRV heat exchangers at about 55% to 95%.
Basis: the range comes from one DOE guide and applies to both unit types. The sources do not give an effectiveness figure for ERV moisture transfer. Ask for the sensible effectiveness the manufacturer states for the exact model.
HRV and ERV Side by Side
The comparison covers the two types on the points the cited sources cover. Where a cell says not published, the sources are silent on that point.
| Question | HRV | ERV |
|---|---|---|
| What it recovers | Sensible heat only | Latent heat (moisture) and sensible heat |
| Effect on indoor humidity | The cited sources do not say an HRV transfers moisture | Transfers some water vapor, which helps indoor humidity stay more constant |
| Winter heat movement | Moves heat from indoor exhaust air to colder incoming outdoor air, lowering heating costs | Same as the HRV, per the sources |
| Summer heat movement | Cooler indoor air cools warmer incoming air, lowering cooling costs | Same as the HRV, per the sources |
| Shared parts | Heat exchanger, one or more fans that move air through the unit, and controls | Same as the HRV, per the sources |
| Sensible effectiveness | About 55% to 95%, per the Building America guide | About 55% to 95%, per the Building America guide |
| Installed price | Not published in the cited sources | Not published in the cited sources |
What to Ask a Contractor
Installation of ducted ventilation equipment belongs to a licensed HVAC contractor, so these questions go to that contractor. The sources give no installed price, so no figure is given here. For a cost context on a whole HVAC system, see our HVAC replacement cost guide.
Air conditioner faults sit outside this comparison air conditioner faults. For an air conditioner that is not cooling, see our air conditioner not cooling guide. Ask these questions at the first visit:
- Is this unit an HRV or an ERV, and does the manufacturer state the moisture transfer for this model?
- Which whole-house type is the design: exhaust, supply, balanced, or energy recovery?
- Do the kitchen and bathroom exhaust fans stay in the design?
- What sensible effectiveness does this model state, and where does it fall in the 55% to 95% range?
- Who runs the ducts, and who handles any new wall or roof penetration and the wiring?
- What is the installed price, and what does it include?
- Will you provide the manufacturer's written specifications for this exact model before work begins?
Ducted ventilation equipment installation belongs to a licensed HVAC contractor. Any new wall or roof penetration and any wiring belong to a licensed electrician. This is reference material that does not replace the contractor's design or the manufacturer's instructions.
Common questions
Is an ERV better than an HRV?
The cited sources do not rank the two types. An ERV transfers some water vapor, which helps indoor humidity stay more constant, and an HRV recovers sensible heat only. Pick the ERV if steadier indoor humidity is the goal, and pick the HRV if heat recovery alone is the goal.
Does an HRV control humidity?
The cited sources do not describe an HRV transferring moisture, so they do not present it as a humidity control. The humidity effect the sources do describe belongs to the ERV, which transfers some water vapor between the airstreams.
Do I still need a bathroom exhaust fan with an ERV?
The sources do not say whether a whole-house ERV replaces a bathroom exhaust fan. They describe kitchen and bathroom exhaust fans as local exhaust that runs intermittently, and they say whole-house mechanical ventilation is still needed in energy-efficient homes. Ask the contractor how the design handles the bathroom fan.
What is the difference between an ERV and an HRV?
An ERV recovers both latent heat (moisture) and sensible heat, while an HRV recovers sensible heat only. Both include a heat exchanger, one or more fans, and controls, and both lower heating and cooling costs by moving heat between the airstreams.
Can I install an ERV myself?
The cited sources do not describe a homeowner installation. Installing ducted ventilation equipment belongs to a licensed HVAC contractor, and any new wall or roof penetration and wiring belongs to a licensed electrician.