Inside Baxi AquaHeat Heat Interface Unit HIU

Heat Interface Units

Baxi AquaHeat HIU

For homes fed with heat from a heat network, the Baxi AquaHeat HI/HWI (Heating Indirect/Hot Water Indirect) is the answer to your apartment’s heating and hot water requirements, and the Baxi AquaHeat HI is perfectly suited to supply heat to communal and commercial premises in your development.

Contact your TSM

Features and Benefits

Multiple outputs

Range of heating outputs from 4kW to 60kW and domestic hot water outputs from 18kW to 57kW.

Easy installation

Optional first fix rail with in-built filling loop and stand-off bracket to allow for installation with various primary and tertiary pipework. Pre-wired with heat meter and Mercurius remote monitoring module.

Highly efficient

Ultra-fast acting, fully modulating PICV perfectly matches energy supply to instantaneous demand and high performance insulation providing very low heat losses.

Remote monitoring and control

Mercurius platform for remote commissioning and monitoring to reduce site on time and giving visibility of errors to improve first-time fix rates.

Reliable

Water Regulation Reg4 Approval. BESA 2023 V4 approval. Covered with a 5-year parts and labour warranty.*

Show Less

Product Literature

Specification Guides

Technical Specifications

BIM Files

Reports

AquaHeat HI

Dimensions

A: HIU width = 540mm

B: HIU height = 857mm

C: HIU depth = 260mm

D: Side Clearance = 30mm

E: Upper Clearance = 100m

F: Lower Clearance = 100m

G: Front Clearance (in operation) = 200mm

AquaHeat HI/HWI

Dimensions

A: HIU width = 540mm

B: HIU height = 750mm

C: HIU depth = 260mm

D: Side Clearance = 30mm

E: Upper Clearance = 100m

F: Lower Clearance = 100m

G: Front Clearance (in operation) = 200mm

Technical Specification

Product Model	HI/HWI - 4/50	HI/HWI - 4/50	HI/HWI - 14/50	HI/HWI - 14/50	HI - 50	HI - 50
	with Heat Meter & Mercurius		with Heat Meter & Mercurius		with Heat Meter & Mercurius
Product Code	7867470	7867472	7867476	7867477	7867474	7867475
Net Weight (Dry) (kg)	27	26.5	27	26.7	30	30
Net Weight (Wet) (kg)	27.5	27	27.5	27.2	31.5	31.5
Gross Weight (packaged) (kg)	27	26.5	27	26.7	30	30
Height (packaged) (mm)	750	750	750	750	857	857
Width (packaged) (mm)	540	540	540	540	540	540
Depth (packaged) (mm)	260	260	260	260	260	260
Heat Loss in keep warm mode high temp (DH 70°C) (kWh / 24h)	0.95	0.95	0.95	0.95	-	-
Heat Loss in keep warm mode low temp (DH 55°C) (kWh / 24h)	0.91	0.91	0.91	0.91

Primary Side
Max operating pressure (bar)	16	16	16	16	16	16
Max operating temperature (˚C)	90	90	90	90	90	90
Maximum primary flow rate (DHW mode) (55 primary / 50 dhw (m3/h)	0.9	0.9	0.9	0.9	-	-
Maximum primary flow rate (space heating mode) (55 primary / 45/35 CH) (m3/h)	0.26	0.26	0.6	0.6	3	3
Maximum primary pressure differential (kPa)	600	600	600	600
Min primary pressure drop req. at Maximum primary flow rate (DHW Mode) (kPa)	16	16	16	16	-	-
Space Heating hydraulics
Max operating pressure (bar)	2.5	2.5	2.5	2.5	3	3
Max operating temperature (˚C)	85	85	85	85	85	85
Safety relief valve setting (bar)	3	3	3	3	3	3
Heating temperature setpoint (min - max) (˚C)	15 - 85	15 - 85	15 - 85	15 - 85	15 - 85	15 - 85
Heating temperature setpoint (default) (˚C)	45	45	45	45	45	45
Heating nominal pump head (kPa)	70	70	70	70	-	-
DHW hydraulics
Max operating pressure (bar)	10	10	10	10	-	-
Min cold water supply pressure (bar)	1	1	1	1	-	-
Hot water temperature setpoint (min-max) (˚C)	40-65	40-65	40-65	40-65	-	-
Hot water temperature setting (default) (˚C)	50	50	50	50	-	-
Electrical
Power supply (V / Hz)	230V ~50 Hz	230V ~50 Hz	230V ~50 Hz	230V ~50 Hz	230V ~50 Hz	230V ~50 Hz
Permanent live required (yes/no)	yes	yes	yes	yes	yes	yes
Power consumption (max space heating output) (W)	65	65	65	65	12	12
Power consumption (standby) (W)	3	3	3	3	3	3
Power consumption (max space heating output, with Mercurius) (W)	75	75	75	75	22	22
Power consumption (standby, with Mercurius) (W)	13	13	13	13	13	13
Minimum external fuse rating (A)	5	5	5	5	5	5
Internal fuse rating (A)	5	5	5	5	5	5
Connection Types / Sizes
Primary network flow	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Primary network return	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Space heating flow	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Space heating return	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Cold water feed	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Domestic hot water flow	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	3/4 ISO G 228 male	1 female	1 female
Space heating safety valve discharge (mm)	15	15	15	15	12	12

Contact your TSM

Our Technical Sales Managers will ensure you get the heating solution that’s right for your project.

Get in touch

Integrated Solutions Brochure

We’re rising to the challenge by streamlining our processes, investing in energy-saving technologies and creating some of the most efficient heating and hot water solutions on the UK & Ireland market.

Download

More Information

Commercial Heating and Hot Water Solutions

Baxi and its associated brands offer a broad range of low carbon and highly efficient heating and hot water solutions for both new build and retrofit commercial applications.

Find out more

Knowledge Centre

Relevant and informative content on a range of topics and key challenges.