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HRV / ERV Rating Metric Explorer

Pick sensible and latent effectiveness and see the bare-core inputs your energy model needs, the AHRI 1060 and CSA C439 rating metrics at standard test points, and how the unit does against ASHRAE 90.1-2025.

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Quick presets: 82/0 HRV · 77/60 core · 77/75 wheel · 70/65

1  ·  Energy-model inputs (bare-core effectiveness, what the software eats)

εs @100%
82.0%
as entered
εl @100%
—
as entered
εs @75%
85.2%
+3.2 pt vs 100%
εl @75%
—
no latent transfer
Enter these four into the model (same values both heating and cooling unless you have mode-specific ratings). Never enter SRE/TRE here. Fan energy is already inside them and the model charges fans separately.

2  ·  Rating metrics at the standard test points

Test point Sensible only Combined (sens + lat) Fs
SensRR = ASRESREERR = ATRETRE
C439 heating 32°F82.0%76.4% 57.5%54.0%70.6%
C439 cooling 95°F82.0%71.2% 28.4%25.6%34.7%
AHRI 1060 summer82.0%71.2% 31.5%28.3%38.5%
AHRI 1060 winter82.0%75.7% 53.9%50.3%66.3%
ASRE / ATRE equal 90.1’s SensRR / ERR exactly under balanced flow, no cross-leakage, adiabatic cabinet, no frost. SRE / TRE are the same numbers with supply-fan energy subtracted and exhaust-fan energy added to the denominator. Fs = sensible share of the available Δh, a property of the test condition, not the unit.

3  ·  ASHRAE 90.1-2025 §6.5.6.1.2.1, non-residential

Program assumptions: cooling design condition = peak-DB (applied consistently); no active humidification in any case, so the heating criterion is the sensible energy recovery ratio. Both compliance paths are reported, and the program is not selecting one.
Path / criterionThresholdThis unitResultApplies to these 7 zones
Path (b): CAN/CSA C439, fixed test conditions
SRE, 32°F heating test≥ 65%76.4%✓ pass +11.4 pt
2A3A4A5A6A4C5B
TRE, 95°F cooling test≥ 50%25.6%✗ fail −24.4 pt
2A3A4A5A6A4C5B
NMTR (= LRMT ≈ εl), 32°F≥ 0.400.00 ✗ fail −0.40
2A3A4A5A6A4C5B
w/ humidification only
C439 Clause 12 rating floor≥ 55% SRE76.4% ✓
Path (a): AHRI 1060, at the project design condition
Sensible energy recovery ratio
heating design, no humidification		 ≥ 50%82.0% ✓ all 6
2A3A✓4A✓5A✓6A✓4C✓5B✓
Enthalpy recovery ratio
cooling design, peak-DB		 ≥ 50%33.5%–40.5% ✗ 5 of 5
2A✗3A✗4A✗5A✗6A✗4C5B
Enthalpy recovery ratio
heating design, w/ humidification		 ≥ 50%— n/a no active humidification assumed; §6.5.6.1.2.1(a)2(ii) governs instead
Path (a) uses your project design condition; path (b) uses the fixed 32°F / 95°F C439 test points. The two paths are not equally stringent, so a unit can pass one and fail the other, which is why both are reported here. Zone chips: 3A✓ meets it, 3A✗ does not, 3A not required. Note the cooling list is driven by cooling severity, not moisture: it includes the dry B zones (0B–4B) and excludes 5B, 6B, the marine C zones and 7–8, so it is not a dry/humid split.

4  ·  Design ERR / SensRR by climate zone (path (a))

Zone / city Heating 99.6% Cooling peak-DB  ·  governs Cooling peak-DP  ·  reference
ERRSensRRERRFsERRFs
2A Houston 61.5%82.0% 39.8%49% 10.9%13%
3A Atlanta 60.3%82.0% 40.5%50% 11.2%14%
4A New York 61.8%82.0% 35.2%43% 9.4%11%
5A Chicago 64.2%82.0% 35.0%43% 13.4%16%
6A Rochester 64.2%82.0% 33.5%41% 10.3%13%
4C Seattle 61.0%82.0% n/m— n/m—
5B Denver 61.7%82.0% n/m— n/m—
n/m = |h1−h3| < 4 Btu/lb. ERR is not a meaningful figure of merit there; report SensRR instead. Design conditions parsed from the project DDY files (TMYx 2011–2025).

What the standard actually says (click to expand)

ASHRAE 90.1‑2025 §6.5.6.1.2.1: Energy Recovery Performance (non‑residential), verbatim

§6.5.6.1.2.1 Energy Recovery Performance

The exhaust air energy recovery performance shall be determined in accordance with one of the following:

a. The exhaust air energy recovery performance of the heat exchanger shall be determined in accordance with AHRI 1060 and shall comply with the following:

  1. In Climate Zones 0A, 0B, 1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 5A, and 6A, at the cooling design condition, the enthalpy recovery ratio at the design minimum outdoor air rate shall be not less than 50%.
  2. In Climate Zones 3 through 8, at the heating design condition:
    1. Where active humidification is provided to spaces served by the system, the heat exchanger's enthalpy recovery ratio at the design minimum outdoor air rate shall be not less than 50%.
    2. Where active humidification is not provided to spaces served by the system, the heat exchanger's sensible energy recovery ratio at the design minimum outdoor air rate shall be not less than 50%.

b. The equipment's energy recovery performance shall be determined in accordance with CAN/CSA C439 and shall comply with the following:

  1. The equipment's sensible recovery efficiency rating at the 32°F outdoor air heating mode test condition shall not be less than 65%. This requirement shall not apply in Climate Zones 0 through 2.
  2. The equipment's total recovery efficiency rating at the 95°F outdoor air cooling mode test condition shall not be less than 50%. This requirement shall not apply in Climate Zones 3C, 4C, 5B, 5C, 6B, 7, and 8.
  3. Where active humidification is provided to spaces served by the system, the equipment's net moisture transfer ratio rating at the 32°F outdoor air heating mode test condition shall not be less than 0.40. This requirement shall not apply in Climate Zones 0 through 2.
  4. The equipment's sensible recovery efficiency and net moisture transfer shall be determined from a rated value, or interpolation of rated values, at an airflow rate not less than the design minimum outdoor air rate.
This is the headline for NEEA: 90.1‑2025 accepts two different rating standards with two different metric families. Path (a) is the AHRI 1060 heat‑exchanger route judged at your project's design condition. Path (b) is the CAN/CSA C439 packaged‑equipment route judged at fixed 32°F / 95°F test points. 90.1‑2022 named neither standard in §6.5.6, so both paths are new.

Dwelling units (§6.5.6.1.1) carry the same two‑path structure with higher heating thresholds (60% instead of 50%) and slightly different zone lists.

What each C439 metric means, and why ASRE/ATRE, not SRE/TRE, equal the 90.1 ratios

CAN/CSA C439‑18 clauses 9.3.3.1, 9.3.3.8, 9.3.3.9  ·  HVI Directory Section III

SRE
Sensible Recovery Efficiency: net sensible energy recovered, adjusted for fan electric consumption, casing heat loss/gain, air leakage, mass imbalance and defrost, as a percent of the potential recoverable sensible energy plus exhaust fan energy.
ASRE
Adjusted SRE: the same, but without the fan-energy adjustment. C439 directs you here for energy modeling when fan power is accounted for separately.
TRE / ATRE
The total (sensible + latent) counterparts of SRE / ASRE.
LRMT
Latent Recovery / Moisture Transfer = moisture recovered ÷ moisture exhausted, corrected for cross-leakage. 0 = none, 1 = complete. This is 90.1's "net moisture transfer ratio."
EAT / R
Exhaust Air Transfer ratio: cross-leakage, taken as the greater of the tracer‑gas and supply‑dilution tests. Net supply airflow = gross × (1 − R).

The structural difference that makes the translation work. C439 divides by ṁmax = max(ṁsupply, ṁexhaust). AHRI 1060 divides by ṁmin. Because a DOAS pressurizes the building (exhaust ≤ supply), ṁmax is the outdoor‑air stream, which is exactly what 90.1's ratios normalize to. So:

ASRE = SensRR and ATRE = ERR, exactly, for a pressurizing DOAS with no cross-leakage, an adiabatic cabinet and no frost. SRE and TRE sit 1–6 points lower because they also carry fan energy. Ordering is always  εs (AHRI) ≥ ASRE ≥ SRE.

Corollary on airflow imbalance: AHRI's ṁmin denominator flatters an unbalanced unit: at 10% exhaust‑short it would publish 85.2% where the delivered SensRR is 76.7%. C439 does not. Cap imbalance at 10% and state it.

What changed from 90.1‑2022
Rating method
2022: not named at all. ERR was defined but no test standard was cited in §6.5.6. 2025 names both AHRI 1060 and CAN/CSA C439.
Airflow basis
New term "design minimum outdoor air rate" (absent from 2022), plus the interpolation rule barring ratings taken at lower airflow, which closes the oversizing loophole, since effectiveness rises as flow falls.
Mode waivers
Moved out of Exceptions 4 & 5 into positive zone lists. Exception count for §6.5.6.1.2 dropped 9 → 7. Same zones in substance, but it resolves an ambiguity in 2022, where Exception 4 waived only the enthalpy requirement and arguably left the sensible one standing in CZ 0–2.
Series ER exception
SERR ≥ 0.40 now carries a specified test condition: 75.0°F DB / 63.0°F WB entering, at the design airflow.
Tables 6.5.6.1.2-1/-2
Numerically identical to 2022. Only the column header changed.
The two paths are not equally stringent. On non‑residential heating, path (a) asks for 50% sensible ERR while path (b) asks for 65% SRE, roughly 66–70% on a SensRR‑equivalent basis once fan energy is added back. A given unit can therefore pass one path and fail the other, which is why this study reports the result on both rather than selecting one.

5  ·  Comparison list

LabelFamilyεs/εl 100% εs/εl 75%SRE htgTRE clg SensRRERR htgERR clg-DP90.1 (b)
Nothing saved yet. Set values and press Add to comparison list.

The formulas being used

ε(φ) = ε100 / [ ε100 + φ^(1−n) (1 − ε100) ] rotary ns=0.2 nl=0.3 plate ns=0.8 nl=0.8 t₂ = t₁ − εs(t₁−t₃) W₂ = W₁ − εl(W₁−W₃) h = 0.240 t + W(1061 + 0.444 t) SensRR = (t₁−t₂)/(t₁−t₃) ERR = (h₁−h₂)/(h₁−h₃) Fs = 0.240Δt / (0.240Δt + 1061ΔW) SRE = [εs·ṁcpΔT − QSF] / [ṁcpΔT + QEF] TRE = [ṁ(h₁−h₂) − QSF] / [ṁ(h₃−h₁) + QEF]