🌡 Preheated Supply Temperature
💰 Annual Heating Savings
Recovery Breakdown
Full Calculation Table
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How to Use the Heat Recovery Wheel Calculator
Choose a typical effectiveness tier, or select Custom to enter manufacturer-rated sensible effectiveness.
Enter the total outdoor airflow that will pass through the wheel, from the commercial ventilation calculator.
Choose the Canadian city closest to your project for representative heating degree day data, or enter custom design temperatures directly.
Click Calculate Heat Recovery to see preheated supply temperature, recovered heating capacity, and estimated annual energy cost savings.
Understanding Sensible Heat Recovery Wheels
A sensible heat recovery wheel transfers only heat, not moisture, between the exhaust and outdoor air streams as it rotates through an AHU or DOAS. This makes it a simpler alternative to a total enthalpy wheel wherever moisture transfer is not wanted or not needed, while still capturing a substantial share of the heating energy that would otherwise be lost through exhaust air, the same recovery obligation ASHRAE Standard 90.1 imposes on many outdoor-air-heavy systems regardless of whether the recovery device also handles moisture.
Why Sensible-Only Instead of Total Energy Recovery
Some applications specifically require avoiding any moisture transfer between exhaust and supply air. Laboratories with fume hood exhaust, hospitals with strict infection control protocols, and any space where cross-contamination risk from moisture carryover is unacceptable are common candidates for sensible-only recovery over a total enthalpy wheel. The energy recovery wheel calculator covers the total enthalpy alternative if latent recovery is acceptable or desired for your application.
Effectiveness and Design Considerations
Sensible heat recovery wheels commonly achieve 65 to 85 percent effectiveness at design airflow, generally comparable to or slightly higher than the sensible component of a total enthalpy wheel, since the media does not need to balance sensible performance against latent transfer, a distinction AHRI's certification program captures by rating sensible and latent effectiveness as separate, independently tested numbers. This calculator applies your specified effectiveness to the temperature difference between winter design outdoor air and typical building exhaust temperature to estimate preheat capacity.
Heating Degree Days and Annual Savings
Heating degree days accumulate the difference between outdoor temperature and a reference indoor temperature across an entire heating season, giving a rough proxy for how much total heating energy a building needs annually, a figure the degree day calculator can pull for your specific city rather than relying on a general regional estimate. A heat recovery wheel in a high-heating-degree-day city like Winnipeg or Edmonton has substantially more annual energy recovery opportunity than the same wheel in a milder climate like Vancouver, since there are simply more cold hours across the year for the wheel to recover heat from.
Run-Around Coils as an Alternative
A run-around coil accomplishes a similar sensible heat transfer goal using a pumped glycol loop connecting a coil in the exhaust airstream to a coil in the outdoor airstream, with no direct air-to-air contact at all. This eliminates even the small cross-leakage risk a rotating wheel carries, which matters in applications with extremely strict contamination control requirements, though the circulating pump itself needs its own sizing, which the pump sizing calculator can help work through. Run-around coils are mechanically more complex and require pump energy, but they offer complete airstream separation that a wheel cannot fully guarantee.
Frost Control at Cold Design Temperatures
Like total enthalpy wheels, sensible heat recovery wheels can develop frost on the exhaust exit side at very cold outdoor design temperatures common across much of Canada. Confirm the specified unit includes a defrost control strategy, whether through wheel speed modulation or a small preheat coil, appropriate to your city's winter design temperature.
Frequently Asked Questions
Choose a sensible-only wheel when moisture transfer between airstreams is undesirable or must be strictly avoided, such as laboratories, hospitals with infection control requirements, or any application where cross-contamination risk outweighs the latent energy savings a total enthalpy wheel would provide. Sensible-only wheels are also simpler to specify since only one effectiveness rating applies. See the energy recovery wheel calculator for the total enthalpy alternative.
Sensible heat recovery wheels commonly achieve 65 to 85 percent effectiveness at design airflow, generally somewhat higher than the sensible component of a comparable total energy wheel, since the wheel media does not need to balance moisture transfer performance against sensible transfer performance.
Heating degree days represent the cumulative difference between outdoor temperature and a reference indoor temperature over a heating season, and they scale directly with how much heating energy a building needs. A city with more heating degree days, such as Winnipeg or Edmonton, gives a heat recovery wheel more total energy to recover over a year compared to a milder climate like Vancouver, even at the same effectiveness rating and airflow.
They serve the same basic purpose but differ mechanically. A heat recovery wheel is a single rotating component installed across both airstreams, while a run-around coil uses a pumped glycol loop connecting separate coils in the exhaust and outdoor air streams, avoiding any direct airstream contact. Run-around coils are sometimes preferred where any air-to-air leakage risk, even sensible-only, is unacceptable, such as certain laboratory exhaust applications.
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