Webasto Air Top EVO 40 Motorhome RV 12v 4kW 13650BTU - Two Outlet Heater Kit

Part Number: AT3900MHKIT12V
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Webasto Air Top EVO 40 Motorhome Twin Outlet Heater Kit

This heater offers optimised fuel efficiency, is compact, and economical requiring less than 1 litre of diesel fuel for 1 hour of maximum, whisper quiet heating. Programmable independent heating (does not use heat from the engine) for many types of RV, Motorhome & Caravan installations.

If this item is not currently in stock please see the alternative Webasto EVO 40 Kit.

Webasto EVO 40 Product Highlights

  • Compact heaters with proven efficiency
  • New and improved technology, e.g. with respect to service life and heat up time
  • Easy installation, underfloor or in the interior
  • Constant ambient temperature, continuous control
  • Automatic altitude function for all Air Top Evo models (see details below)
  • Low power consumption, quiet operation
  • Intelligent Blower Control

This Webasto Air Top Evo 40 heater kit comes with a complete installation kit for your vehicle. Supplied with a rotary rheostat temperature control. We also offer the option of the MC Air Top EVO Control or digital timer. This kit includes ducting & air outlets to move the warmth to where you need it.

For additional accessories, please see our range of air outlets, heater ducting and digital controllers to enable a truly bespoke and cost-effective heating solution.

Webasto Air Top EVO 40 Twin Outlet Kit contents;

Everything you need to complete a professional installation

  • Webasto Air Top Evo 40 12 volt diesel heater with rotary rheostat temperature control
  • (Upgrade to 7 day Timer Programmer or MC Air Top EVO Control – please enquire if required)
  • All electrical harnesses and connections
  • Steel heater mounting plate, to protect wood or composite floors
  • Exhaust silencer included for quiet operation
  • 1 x 1m & 1 x 0.5m of stainless steel exhaust pipe with clamps &
  • (Please see our section for additional lengths 24mm exhaust pipe if required)
  • Combustion Intake silencer 
  • Includes 1m x 60mm flexible ducting and 1.5m x 90mm flexible ducting
  • (Additional ducting required? Please see our ducting page.)
  • 1 x Air entry grille
  • 1 x 90mm Open vent & back nut
  • 1 x 60mm closable vent & back nut
  • 1 x 90x60x90mm ‘Y’ branch
  • (Please see our ducting accessories for additional air outlets, Y Branches & vents)
  • Fuel system with 5m plastic fuel pipe, complete with fuel metering pump & anti vibration mountings
  • Fuel standpipe (in tank length 450mm)
  • All necessary clips and screws for standard installation included
  • Comprehensive installation manual
  • Webasto 24 months warranty.

High Altitude Operation

This is a high altitude sensing heater. For high altitude operation add the Webasto Air Heater Multi Control HD Timer

Two Year Warranty

This is a genuine Webasto Warranted RV, Motor-home & Caravan heater kit. 24 months Genuine Webasto UK Warranty from Butler Technik

Heater applications also Include:

  • Vans and Small Buses
  • RV's, Caravans & Mobile Homes
  • Campervans
  • Horse boxes
  • 4 x 4 Vehicles

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Please Note: Delivery prices quoted are excluding VAT.

Deliveries are made from Monday to Friday excluding Bank and National Holidays.

Next Working Day Shipping* is available in UK Mainland for all orders placed before 15:00hrs. Orders placed after 15:00hrs will be dispatched the following working day on a next day service.

Orders placed on a Saturday or Sunday will be despatched the following Monday (except Bank Holidays) for expected delivery following business day (Tuesday).

For Next Business Day Delivery, please select Next Day.

Standard 2-day shipping* is available to Scottish Highlands and Islands orders placed before 15:00hrs on stocked items. Items are despatched promptly sameday. UK Courier services are typically 2 day delivery for remote UK postcodes.

WEEKEND deliveries in the UK may be possible if required at additional cost. For WEEKEND delivery quotation please call our Sales Team prior*

Standard carriage / Free-shipping - please allow 2-5 working days from clearance of payment for delivery. Typically however delivery is much quicker and 98% of orders are delivered to UK addresses within 24 - 48 hours after dispatch from warehouse.

Delivery Times - Deliveries are made Monday to Friday (excl. public holidays) typically 2-5 working days from date of order for in-stock items if the FREE DELIVERY option is chosen. An email will be sent to inform you of dispatch of goods and due delivery date. Next Day UK delivery may be selected at checkout for an additional cost.

  • Free worldwide delivery will not be available if one of the following is applicable to your order:
  • Your order has a total weight exceeding 18kgs
  • You already have a discount code applied to your order
  • Your basket contains a special order item that requires shipping additionally.

Our returns policy does not include manufacturer warrantable items. Please speak to our support department or email sales@butlertechnik.com if you believe your item has failed within warrantable circumstances, or if you wish to return an item for refund.

Refunds and Right to Cancel

You have the right to cancel your order within a 14 (fourteen) day "cooling off period", which starts the day after you receive your items. You can apply for a refund within 30 (thirty) days from the date of invoice.

Prior Notification of Intent

If you wish to cancel an order or submit a refund request under the UK Consumer Protections (Distance Selling) Regulations 2000, you must inform ButlerBus Technik Ltd of your intention to cancel or return your order by either phone, email or post within the 14 (fourteen) day cooling off period for order cancellation, or 30 (thirty) day period for refunds.

When Butlerbus Technik has received your request you will receive confirmation and given authorisation to return goods. Please quote and include your original invoice number. All goods must be in a re-saleable condition.

You will be required to return goods at your cost by an insured and trackable method. If goods go missing we will only consider a request for refund on proof of completed receipt/delivery of goods to Butler Technik from your nominated courier. Once we have received goods we will then issue you a full refund less any delivery charges.

If you are unable to arrange a return please contact us. We can arrange collection on your behalf but a charge will be made which will be deducted from your refund total.

If a delivery charge was made on the original purchase this will not be refunded as this is a service which is concluded at the point of order.

Orders that have already been processed and/or dispatched cannot be cancelled; they must be returned to ButlerBus Technik Ltd for refund following receipt of goods by customer.

We will do our very best to assist and enable a quick refund process upon receipt of returned items.

Thank you for your continued understanding during this process

Returns address
ButlerBus Technik Ltd
Bridge Road
United Kingdom

    Specific Terms:
  • All costs relating to return shipping of correctly supplied goods shall be the responsibility of the purchaser.
  • ButlerBus Technik Ltd are not responsible for any shipping or insurance charges relating to return of goods.
  • Please be aware that ButlerBus Technik Ltd may NOT be able to accept for full or partial refund/credit any items that have been prior installed by the customer before return. Such goods/components shall be deemed 'used' and therefore unable for subsequent resale.
  • Specifically, but not exclusively, the return of prior installed electronic items used for purchaser diagnostic or trouble-shooting purposes shall not be considered for full refund.
  • The decision to refund or partially refund prior installed items shall remain solely at the discretion of ButlerBus Technik Ltd.
  • The decision to refund or partially refund goods returned beyond 30 days after original date of sale shall remain solely at the discretion of ButlerBus Technik Ltd.

Your statutory rights are unaffected by the above. Consumers other than Business trade customers are further protected by UK Consumer Protection (Distance Selling) Regulations 2000.

If you have any questions please ask our support department prior to returning any items.

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