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AirGreen × TOSOT · Sold and installed by AirGreenTOSOT tri-zone at AirGreenThree heads on one outdoor unit, with Lomo 23 and LomoPlus UltraHeat compressors.
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TOSOT · Multi-zone · Tri-zone · updated November 5, 2026

TOSOT tri-zone: your line-set plan, checked against the sheet

Three heads means three line sets leaving the same outdoor unit. Enter your home’s distances: the tool compares them with the limits in the chosen compressor’s TOSOT sheet and works out the refrigerant to add.

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  • 7tri-zone compressors online
  • 82 ftat most per head, on six of the seven compressors
  • 262 ftof line in total on the 42,000 LomoPlus UltraHeat
  • 10 ftat least per head, on every sheet
01 · Your line-set plan

Three heads, three lengths: check your plan against the TOSOT sheet

Pick the compressor, then enter the line length to each head and the largest heights, in feet. The tool checks the sheet’s five limits and works out the refrigerant to add.

Compressor

TM24H5O: your plan is within the sheet’s five limits.

  1. WithinFarthest head: 60 ft (18.3 m)Sheet maximum: 82 ft per head.
  2. WithinClosest head: 25 ft (7.6 m)Sheet minimum: 10 ft per head.
  3. WithinTotal of the three lines: 125 ft (38.1 m)Sheet maximum: 230 ft in total.
  4. WithinOutdoor unit ↔ head height: 15 ft (4.6 m)Sheet maximum: 26 ft, up or down.
  5. WithinHeight between two heads: 10 ft (3.0 m)Sheet maximum: 26 ft.
  6. ChargeRefrigerant to add: about 5.4 oz(125 − 98) × 0.2 oz per foot, per the sheet. The sheet counts the liquid line only. TOSOT sheet of November 4, 2024.
See this compressor as a tri-zone

LomoPlus UltraHeat: TOSOT sheets of November 4, 2024. Lomo 23: TOSOT sheets read on October 28, 2026. Line lengths between the outdoor unit and each head, as the sheet defines them. The actual route, supports and condensate drain are checked on site.

AirGreen × TOSOT

TOSOT tri-zone units, live

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

Three limits that decide the route

01

Only the liquid line counts

For the refrigerant charge, the LomoPlus UltraHeat sheets count the liquid line length only: below the pre-charged length, nothing to add; beyond it, 0.2 oz per foot (0.21 oz on the 42,000 compressor).

TOSOT sheets TM24H5O, TM36H5O and TM42H5O, “Piping requirement” section (November 4, 2024).

02

Pre-charged for 98 or 131 ft

The 24,000 LomoPlus UltraHeat ships charged for 98 ft of line, the 36,000 and 42,000 for 131 ft. On the Lomo 23 side, the sheets read on October 28, 2026 gave 98 ft for the 24,000 and 131 ft for the 30,000 to 42,000.

TOSOT sheets TM24H5O to TM42H5O (November 4, 2024); TM24H4O to TM42H3O (read on October 28, 2026).

03

Height: 26 to 49 ft

Between the outdoor unit and a head, the 24,000 LomoPlus UltraHeat sheet allows 26 ft; the 36,000 and 42,000 sheets, 49 ft. The 30,000 to 42,000 Lomo 23 units also allow 49 ft, but only 25 ft between two heads.

Same TOSOT sheets.

03 · Side by side

The seven tri-zone compressors: line-set limits

The limits in each TOSOT sheet, side by side, in feet.

CompressorTotalPer headOutdoor ↔ headBetween headsPre-charged for
Lomo 23 · 24,000TM24H4O197 ft10 to 65 ft33 ft33 ft98 ft · then 0.21 oz/ft
Lomo 23 · 30,000TM30H4O230 ft10 to 82 ft49 ft25 ft131 ft · then 0.21 oz/ft
Lomo 23 · 36,000TM36H4O246 ft10 to 82 ft49 ft25 ft131 ft · then 0.21 oz/ft
Lomo 23 · 42,000TM42H3O246 ft10 to 82 ft49 ft25 ft131 ft · then 0.21 oz/ft
LomoPlus UltraHeat · 24,000TM24H5O230 ft10 to 82 ft26 ft26 ft98 ft · then 0.2 oz/ft
LomoPlus UltraHeat · 36,000TM36H5O246 ft10 to 82 ft49 ft49 ft131 ft · then 0.2 oz/ft
LomoPlus UltraHeat · 42,000TM42H5O262 ft10 to 82 ft49 ft49 ft131 ft · then 0.21 oz/ft

Lomo 23: TOSOT sheets read on October 28, 2026. LomoPlus UltraHeat: TOSOT sheets of November 4, 2024. 1 ft = 0.3048 m.

04 · Multi-zone

The multi-zone pages, each with its question

R-410ADual zoneYour pair of heads, compressor by compressor.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.R-410ALomo 23 tri-zoneThe compressor’s ceiling with three heads.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 TM18H5O, TM24H5O, TM36H5O and TM42H5O, dated November 4, 2024, tosot.com, read on November 5, 2026 (specifications, indoor-unit combination table and note on the capacity ratio).
  2. 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.

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.