Baxi 800 Heat

Baxi 800 Heat Only Boiler

Heat Only Boilers

Baxi 800 Heat

The Baxi 800 Heat includes a compact Adey MagnaClean Micro2 system filter to protect the boiler and heating system. This boiler can be installed on open vent or sealed systems and has an optional in-case rear flue for a neater installation.

Features and Benefits

Multiple outputs

Available in outputs of 16, 25 and 30kW


Top central or optional in-case rear flue giving flexibility to site


Only 17.4kg installer lift weight (30kW is 19.5kg) for easy installation


Easy-fit wall mounting bracket featuring a positive fix and audible lock, so you know it’s secure


No pump overrun or permanent live required, saving time and money during installation
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Product Literature

Installation and Service Manuals

Installation and Service Manuals

User Guides

User Guides

Product Documentation

No documentation available.

Specification Guides

Specification Guides

Product Documentation

No documentation available.

Product Fiche

Product Fiche

Baxi Heat Only Boiler Dimensions


A: Boiler Width = 370mm

B: Boiler Height = 625mm

C: Boiler Depth = 270mm

D: Side Clearance = 5mm

E: Upper Clearance = 190mm*, 35mm* if used rear flue

F: Lower Clearance = 120mm*, 35mm* in 300m deep wall cupboard

G: Front Clearance= 5mm* in operation (500mm for servicing)

Technical Specification

Product Model




Product Code774986677498687749869
Controls and accessories
Operating mode selector switch with reset (Yes/No)YesYesYes
User adjustable CH temperature (Range - e.g. 45° to 82°)YesYesYes
LED temp/status/fault diagnosis display (Yes/No)YesYesYes
Baxi twin channel wired programmer -7212443OptionalOptionalOptional
Baxi room thermostat -720971601OptionalOptionalOptional
Boiler Plus ErP (%)
SAP 2009 annual efficiency (PCDB/SEDBUK) %
NOx class666
ErP Product Information
NOx (mg/kWh)202424
Sound Power Level, Indoors (LWA dB)394549
Space Heating Efficiency ClassAAA
Heat Input CH - kW max gross (QnHs)18.3228.6234.35
Heat Input CH - kW min gross (QnHs)8.598.598.59
Heat Output CH (non condensing) kW (Pn)162530
Heat Output CH (non condensing) kW (Pn)
Gas supply connection (mm)222222
Inlet supply pressure (natural gas) mbar202020
Maximum gas rate (m3/hr)1.752.733.27
Mechanical and hydraulic
Compartment ventilation required (Yes/No)NoNoNo
Flow / return pipe size (mm)222222
Condensate discharge pipe size (mm)21.521.521.5
Electrical supply (Volts/Hz)230V/50Hz230V/50Hz230V/50Hz
Permanent live required (Yes/No)NoNoNo
Switched live (Yes/No)YesYesYes
Electrical power cable fitted as standard (1m of 3 core)YesYesYes
Power consumption (Watts) 203344
External fuse rating (Amps)333
Internal fuse rating1.6T1.6T1.6T
Boiler IP rating (electrical protection) -Approval categoryIPX4DIPX4DIPX4D
Pump overrun (Yes/No)NoNoNo
Concentric flue system
Standard telescopic concentric flue (Length in mm)315-500315-500315-500
Horizontal and Vertical concentric (60/100 mm) - Max equivalent length (m)666
Horizontal and Vertical concentric (60/100 mm) - Reduction per 135° bend (m)
Horizontal and Vertical concentric (60/100 mm) - Reduction per 93° bend (m)111
Horizontal and Vertical concentric (80/125mm) - Max equivalent length (m)121212
Installer lift weight (boiler) Max (kg)17.417.419.5
Gross packaged boiler weight (kg)21.321.321.3

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