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AirGreen × TOSOT · Sold and installed by AirGreenThe Lomo 23 tri-zone at AirGreenThree rooms on one Lomo 23 compressor, from 24,000 to 42,000 BTU/h.
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TOSOT · Multi-zone · Lomo 23 tri-zone · updated November 5, 2026

Lomo 23 tri-zone: the compressor’s ceiling

With three heads, the system output levels off. On the 24,000 Lomo 23, the sheet gives 26,000 BTU/h in cooling whether the heads add up to 27,000 or 36,000 BTU/h.

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  • 4Lomo 23 tri-zone compressors online
  • 26,000 BTU/hceiling of the 24,000 in cooling, three heads
  • 38,300 BTU/hheating, the highest trio on the 36,000
  • -21 °Cheating, per the TOSOT sheets
01 · The compressor’s ceiling

Three heads: how high does the system go?

For each Lomo 23 compressor, the output the TOSOT sheet gives the system with three heads, trio by trio, next to the sum of the heads.

Compressor · BTU/h

Mode

TM24H4O, three heads in cooling: 26,000 to 26,001 BTU/h for 27,000 to 36,000 BTU/h of heads (sheet read on October 28, 2026).

Lomo 23 · 24,000 BTU/hTM24H4O · cooling · sheet read on October 28, 2026
  1. 9,000 + 9,000 + 9,00027,000 of heads26,001 BTU/h96% of the heads’ sum
  2. 9,000 + 9,000 + 12,00030,000 of heads26,000 BTU/h87% of the heads’ sum
  3. 9,000 + 12,000 + 12,00033,000 of heads26,000 BTU/h79% of the heads’ sum
  4. 9,000 + 9,000 + 18,00036,000 of heads26,000 BTU/h72% of the heads’ sum
  5. 12,000 + 12,000 + 12,00036,000 of heads26,001 BTU/h72% of the heads’ sum

Red mark: the sum of the heads, on the same scale.

The ceilingFor 5 trios, from 27,000 to 36,000 BTU/h of heads, the system gives 26,000 to 26,001 BTU/h in cooling.
See this compressor as a tri-zone

TOSOT sheets for the Lomo 23 compressors, read on October 28, 2026; system outputs at AHRI test conditions (95 °F cooling, 47 °F heating). For the 42,000 compressor, only the cooling table was recorded. The bars share one scale across the four compressors.

AirGreen × TOSOT

TOSOT Lomo 23 tri-zone units, live

Each product page: outdoor model, AHRI number and the heads offered.
02 · Did you know

Three things the TOSOT tables show

01

More heads, not more output

On the 24,000 Lomo 23, the five trios listed all give 26,000 or 26,001 BTU/h in cooling, whether the heads add up to 27,000 or 36,000 BTU/h.

TOSOT sheet TM24H4O, read on October 28, 2026.

02

Heating comes out ahead

With three heads, the 36,000 Lomo 23 gives more in heating than in cooling: 38,300 BTU/h against 32,760 for 12,000 + 18,000 + 18,000.

TOSOT sheet TM36H4O, read on October 28, 2026.

03

No 24,000 wall head on the 42,000

TOSOT’s brochure reserves the 24,000 size for cassette, ducted and floor-ceiling heads on the 42,000 BTU/h compressor, not wall heads.

TOSOT “Heat Pumps” brochure in English.

03 · Side by side

The four Lomo 23 compressors with three heads

How many trios each sheet lists, and the spread of system output across its trios.

CompressorTrios listedHeads in total (BTU/h)System, coolingSystem, heating
Lomo 23 · 24,000TM24H4O527,000 to 36,00026,000 to 26,00129,000 to 29,001
Lomo 23 · 30,000TM30H4O827,000 to 42,00025,500 to 30,20028,500 to 31,500
Lomo 23 · 36,000TM36H4O1227,000 to 48,00024,600 to 34,10027,000 to 38,300
Lomo 23 · 42,000TM42H3O1227,000 to 48,00024,600 to 37,500not recorded

TOSOT sheets read on October 28, 2026, AHRI test conditions.

04 · Multi-zone

The multi-zone pages, each with its question

R-410ADual zoneYour pair of heads, compressor by compressor.R-410ATri-zoneYour line-set plan, checked against the sheet.R-410AFour zonesFour heads against one compressor.R-410AFive zonesWhat TOSOT really publishes for five rooms.R-410AUltraHeat dual zoneWhat the compressor keeps in deep cold.R-410AUltraHeat tri-zoneThe head trios TOSOT accepts.R-410ALomo 23 dual zoneStarting with a single head.TOSOTAll multi-zone unitsBoth compressor families, from 2 to 5 rooms.
AirGreen × TOSOT

The right model is chosen at your place, not on a grid

We look at the room, the insulation and the electrical panel, then we propose the model, the quote and the LogisVert amount that applies.

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  • Sold and installed by AirGreenMontreal, Laval, Longueuil, South Shore and North Shore.
  • RBQ 5645-9605-01Subclasses 15.8 Ventilation, 15.10 Refrigeration and 16 Electricity.
  • LogisVertHydro-Québec never solicits by phone or door to door for LogisVert.
Sources

Sources and reading dates

  1. TOSOT, submittals TM18H4O, TM24H4O, TM30H4O, TM36H4O and TM42H3O, undated, read on tosot.com on October 28, 2026 (specifications and combination tables); these files were no longer online there on November 5, 2026.
  2. ENERGY STAR and NEEP: no record for AHRI numbers 10064017, 10064019, 10064021, 10064023 and 10064025 (searched on October 28, 2026).
  3. Hydro-Québec, “Heat pump search tool”, list of October 7, 2026 (LogisVert amounts).
  4. TOSOT, “Heat Pumps” brochure in English, undated: note on the 24,000 BTU/h size with the 42,000 BTU/h compressors.

LogisVert amounts come from Hydro-Québec’s list on the date shown; only Hydro-Québec confirms the grant. AHRI numbers are those on our product pages, unchanged.