Knowledge base / Brands / Daikin / Altherma 3 H MT

Daikin · Heat-pump or fixed-AC model

Altherma 3 H MT

Daikin Altherma 3 H MT is a current R32 medium-temperature air-to-water family in 8, 10 and 12 kW capacity classes.

Specifications

SpecificationValue
Typeair-source, air-to-water medium-temperature split system
Supply phasessingle or three, depending on EPRA code
Rated output (kW)8, 10 or 12 capacity class
Maximum flow temperature (°C)65 at -15°C outdoor air by heat-pump operation, under the manufacturer's stated condition
RefrigerantR32 in the outdoor circuit
Minimum operating temperature (°C)-28
Sound pressure at stated distance (dB)41 to 47.1 on current UK package pages
MCS certifiedcurrent exact EPRA08, EPRA10 and EPRA12 combinations were present on 23 July 2026
Warranty (years)2 standard; extensions depend on registration, installer route, maintenance and terms

Altherma 3 H MT is Daikin’s medium-temperature R32 family in 8, 10 and 12 kW outdoor-unit classes. The corresponding outdoor codes begin EPRA08, EPRA10 and EPRA12.

The temperature class is part of the name

Daikin states that this outdoor range can deliver 65°C leaving water at -15°C outdoor air by heat-pump operation and can operate down to -28°C. Those are operating-envelope statements. The heat output and electrical input at a design condition still come from the exact code’s performance data.

MT is distinct from Altherma 3 H HT, whose outdoor range starts at 14 kW and has a higher stated leaving-water condition. It is also separate from Altherma 3 R and the R290 Altherma 4 H.

Indoor arrangements

The F package uses a floor-standing indoor hydraulic unit with an integrated 180 or 230 litre hot-water cylinder. The W package uses a wall-mounted indoor unit and can connect to separate hot-water storage or a thermal store. Heating-only, reversible and backup-heater versions add further suffixes.

Current UK package pages give outdoor sound pressure from 41 to 47.1 dB(A). Sound pressure depends on the stated test arrangement and is not interchangeable with the sound-power figure used in a planning assessment.

Certified combinations and warranty

Exact EPRA08, EPRA10 and EPRA12 indoor-and-outdoor combinations were current in the MCS (Microgeneration Certification Scheme) Product Directory on 23 July 2026. A record should retain both codes because changing the indoor unit can change the certified combination and electrical specification.

Daikin’s live UK warranty page stated two years as standard at the review date. It described longer air-to-water terms through Stand By Me, subject to registration, installer route, maintenance and the full conditions. The installed system’s registration certificate establishes its actual cover.

Brand

Daikin

Reference type

Heat-pump or fixed-AC model

Last reviewed

23 Jul 2026

Current status

Current in the manufacturer's UK range.