C91-8FB-974 3.5kw Lightweight Heater 24v T7Design Available at T7Design

T7Design 3.5kw Lightweight Heater 24v

T7Design | AN08 AN Hose Adapter for 3.5kw Heater

AN08 AN Hose Adapter for 3.5kw Heater

T7Design 3.5kw Lightweight Heater 12v

£168.00 £140.00
Availability: Out of Stock
This product is currently out of stock but can still be back-ordered. Please contact us for an accurate ETA.

3.5kw Lightweight Heater 12v

The 3.5kw Lightweight Heater is our second smallest and lightest hot water based heater after the 2.2kw Micro Heater, sacrificing a little weight for performance this unit can be used as a more powerful defrost heater and can also provide more cabin heat.

The heater uses a specially designed copper & brass heater core offering excellent heat transfer capabilities for its size, this is accomplished using a high flow core design, high fin density and ultra-thin wall tube. A lightweight and efficient axial fan is used to draw air through the heater core and expel it through 4x 51mm (2") outlet nozzles. The Axial fans are at minimum 50% lighter and use 25% of the power over traditional centrifugal blowers.

The 3.5kw Lightweight Heater is ideal for use in small vehicles for defrosting windscreens, or as a secondary heating device for vehicles if you already have a heated windscreen. If you are planning on ducting into the pre-moulded under dash trunking/ducting system, then it would be recommended to step up a size to the 5kw Midi Heater with its more powerful 3 speed centrifugal blower.

The heater comes with 1/2" hose fittings as standard, however AN08 hose adapters are available as an optional extra to allow the fitment of braided hose if regulations do not allow standard rubber heater hose to be run in the interior of the vehicle.

Typical weight savings over a production vehicle heating system can be in excess of 6kg.

Specification Metric Imperial & Other
Heat Output 3.5 kw 11,900 BTU
Airflow 322 m3/hr 190 cfm
Weight 1.15 kg 2.53 lbs
Hose Size ∅ 13mm ∅ 1/2"
Air Nozzle Size 4x ∅ 51mm 4x ∅ 2"
Noise Level 60 dB (Max Fan Speed) -
Voltage 12v
Current Continuous / Startup 2a / 3a
Fan Speeds Single Speed
Enclosure Construction Aluminium Enclosure with Black Powdercoat Finish
Heater Core Design Copper & Brass Core with Copper Fins
Manufacturer T7Design Ltd
Part Number 258-319-2B8
Wiring Information

The fan has no onboard speed control, the simplest way to operate this fan is to use an ON/OFF toggle or rocker switch. If you would like to adjust the fan speed please see our PWM fan controller.

Wire Colour Use
Red Wire +12v
Black Wire Earth

Please ensure your supply is fused appropriately, it is recommended to use a 3a fuse and that your cable is rated higher than the fuse.

3.5kw Lightweight Heater Dimensions
  • Please note that a corrosion inhibitor such as glycol or anti-freeze should be used to prevent corrosion and prolong the useful life of all components used in the vehicles cooling system.
  • Not suitable for use in cooling systems that run at pressure higher than 2 bar (28 psi).
  • Ensure the heater is installed with the hose connections facing up or horizontal, anything less and the performance could be compromised due to trapped air within the heater core.
More Information
Air Hose Size 50 - 51mm (2")
Fan Speeds 1 Speed
Motor Type Brushed
Hose Size 13mm, 1/2"
Voltage 12v DC
Manufacturer T7Design

Shipping Information & Charges

VAT is included on the UK prices below, no VAT is applicable on ROW prices.

European Customers: We offer a next working day delivery service to most European countries, please get in touch for pricing.

ROW Customers: If you would like a more accurate shipping quote or a faster service via DHL please get in touch with your requirements.

United Kingdom & Northern Ireland

Service GBP 0 - 50 (inc VAT) GBP 50+ (inc VAT)
RM Second Class 3.60 N/A
RM First Class 4.20 N/A
DPD / DHL Next Working Day 9.00 9.00
DPD Next Working Day by 12am 16.50 16.50
DPD Saturday All Day 15.00 15.00
DPD Saturday by 12am 39.50 39.50
DPD Sunday All Day 19.50 19.50

Scottish Highlands & Islands, Channel Isles, Scilly Isles, Isle Of Man, Isle of Wight
Service GBP 0 - 50 (inc VAT) GBP 50+ (inc VAT)
RM First Class 4.20 N/A
DPD / DHL Two Day 17.30 17.30


DHL Tracked Delivery. Approx 2 - 7 days depending on distance from the UK.

Country Cost in GBP
AUT - Austria 30.00
BEL - Belgium 25.00
BIH - Bosnia and Herzegovina 50.00
BGR - Bulgaria 45.00
HRV - Croatia 35.00
CZE - Czech Republic 35.00
CHE - Switzerland 42.00
DNK - Denmark 30.00
EST - Estonia 35.00
FIN - Finland 35.00
FRA - France 35.00
DEU - Germany 28.00
GIB - Gibraltar 46.00
GRC - Greece 40.00
HUN - Hungary 35.00
IRL - Ireland 25.00
ISL - Iceland 50.00
ITA - Italy 32.00
LVA - Latvia 46.00
LTU - Lithuania 45.00
LUX - Luxembourg 26.00
NLD - Netherlands 26.00
NOR - Norway 45.00
POL - Poland 35.00
PRT - Portugal 35.00
ROU - Romania 45.00
SRB - Serbia 45.00
SVN - Slovenia 35.00
SVK - Slovakia 35.00
ESP - Spain 30.00
SWE - Sweden 35.00

Rest Of World

Below are the most popular countries we ship to world-wide. If your country is not listed please get in touch for a quote.

DHL Express: We offer shipping via DHL, please get in touch for pricing and more information on their Worldwide 1-2 day services.

Country Cost in GBP
CAN - Canada 60.00
JAM - Jamaica 50.00
JPN - Japan 70.00
MLT - Malta 58.00
MYS - Malaysia 50.00
NZL - New Zealand 52.00
RUS - Russia 50.00
ZAF - South Africa 49.00
THA - Thailand 55.00
USA - United States of America 70.00
SGP - Singapore 90.00


By Order Value: GBP 0 - 50 GBP 50 - 120 GBP 120+
AUS - Australia 40.00 60.00 80.00