

Webasto AirTop Evo 40 – 12V Diesel Heater Kit (4.0kW)
Enhance your vehicle’s comfort and efficiency with the Webasto AirTop Evo 40. Engine-independent, highly fuel-efficient, and built with advanced safety features, this heater is ideal for a wide range of road and marine applications. With variable heat output from 1.5kW to 4.0kW, it provides reliable warmth wherever your journey takes you.
Certified for installation in passenger areas and near hazardous materials.
Engine-Independent Heating: Operates without relying on engine heat, making it suitable for vans, motorhomes, commercial vehicles, and more.
Altitude Ready: Fully functional up to 2,200 meters as standard. For higher altitude requirements, please contact us for guidance.
Safety Certified: Approved for use in passenger compartments and near dangerous goods.
Webasto AirTop Evo 40 Heater (12V Diesel)
Choice of controller (select from the options below)
Full electrical harness set and connectors
1m stainless steel exhaust pipe
1m combustion air intake pipe
Fuel T-Piece Kit (standpipe upgrade available on request)
Air entry grille
Full set of clips, brackets, and screws
Complete fuel system: 8m plastic fuel line, metering pump & anti-vibration mount
Full installation manual booklet
8mm fuel T-piece included (standpipe not included – please ask if required)
Webasto 36-month warranty handbook
Vans & Small Buses
Camper Vans
RVs, Motorhomes & Caravans
4x4 Vehicles
Horseboxes
Marine Applications
Replacement Installation
We can build bespoke kits tailored to your installation requirements.
If you need additional parts, please get in touch or browse our heater Installation Accessories tab above.
Select your controller from the options below and configure your kit to suit your build.
Warranty Terms
Mellor Solutions Ltd trading as Mellor Online is an authorised distributor of heating parts and heater kits for the vehicle and marine markets.
Warranty Coverage:
Additional Services:
Returning a Heater:
Customer Responsibilities:
Exclusions and Important Notes:
Returns Policy
Our returns policy applies to consumer purchases only (not business or trade orders).
Our returns policy does not cover items that fall under manufacturer warranties. If you believe your item is eligible for warranty service or you wish to return an item for a refund, please contact our support team or email us at sales@melloronline.co.uk.
Refunds and Cancellation Rights
You have the right to cancel your order within a 14-day cooling-off period, starting the day after you receive your items. Refund requests can be submitted within 30 days of the invoice date. Refunds will be processed within 14 days of receiving the returned goods.
Notification of Intent to Cancel
To cancel an order or request a refund under the UK Consumer Contracts Regulations 2013, you must inform Mellor Solutions Ltd trading as Mellor Online of your intention by phone, email, WhatsApp, or post within the applicable period. This is 14 days for cancellations and 30 days for refunds.
Upon receiving your request, we will send you a confirmation and authorization to return the goods. Please include your original invoice number with your return. All items must be in a resaleable condition
Upon receiving your request, we will send you a confirmation and authorization to return the goods. Please include your original invoice number with your return. All items must be in a resaleable condition.
Return Shipping
You are responsible for returning goods using an insured and trackable shipping method at your expense. We will only consider refund requests if there is proof of delivery to Mellor Solutions Ltd trading as Mellor Online from your chosen courier. Once we receive the goods, we will issue a full refund minus any delivery charges.
If you cannot arrange a return, please contact us. We can arrange collection for you, but a fee will apply, which will be deducted from your refund.
Please note that delivery charges from the original purchase are non-refundable, as the service is completed once the order is placed.
Processed and Dispatched Orders
Orders that have already been processed or dispatched cannot be canceled; however, they can be returned for a refund once received by the customer.
We strive to facilitate a prompt refund process upon receiving returned items.
Return Address
FAO: RETURNS
Mellor Online
139 Manor Road
Ossett
West Yorkshire
WF5 0LQ
United Kingdom
Specific Terms
Your Statutory Rights
Your statutory rights are unaffected by the above terms. Consumers, excluding business trade customers, are further protected under the UK Consumer Contracts Regulations 2013.
For any questions, please contact our support department before returning any items.
Shipping Information: UK & Worldwide
UK Delivery:
International Delivery:
| Installation Guide (PDF) |
| New Evo 40 info (PDF) |
| Smart Controller Info (PDF) |
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