Webasto Parking Heater Water Pump U4847 12V

Parking heaters run their own small coolant circuit, separate from the moment the main engine starts, and that circuit depends entirely on its own water pump to move heat where it’s needed. The Webasto U4847 12V is a direct-fit replacement for that pump.

Key Benefits

Here’s what this part brings to the job:

• Matches the original pump’s voltage and mounting specification for a direct electrical and physical fit
• Keeps the parking heater’s independent coolant circuit running so cabin and engine pre-heat continues to work correctly
• Sourced directly from Webasto, the original manufacturer of the parking heater unit itself, not a third-party aftermarket equivalent
• Matched to the original part number rather than a universal or generic substitute

What’s In The Box

• Brand: Webasto
• Part / Model Number: U4847 12V
• Model: U4847 12V
• Voltage [V]: 12

A note on this listing: the specification data available for this part from our supplier feed is limited to what’s shown above — we haven’t filled in placeholder dimensions or ratings we can’t verify. If you need additional specifications to confirm fitment against your Webasto unit, contact us and we’ll track them down before you order rather than have you guess.

Application & Use Case

Webasto parking heaters (also called auxiliary heaters) are self-contained, fuel-fired units that heat coolant independently of the vehicle’s main engine, letting you warm the cabin and pre-heat the engine before a cold start without idling. Because that heat has to circulate somewhere, the unit has its own small water pump moving coolant through the heater’s internal heat exchanger and into the vehicle’s existing heating circuit. When this pump fails, the parking heater may still ignite and run its burner cycle, but coolant won’t circulate properly, which typically triggers a fault code on the unit’s control module and shuts the heater down as a safety measure rather than letting it run without cooling flow.

Confirm the U4847 12V matches your specific Webasto unit’s model and voltage before ordering — parking heater water pumps are matched to the specific heater model, not to the vehicle, so the same pump won’t necessarily fit a different Webasto unit even on the same car. For manufacturer-specific installation and diagnostic guidance, see Webasto’s own technical resources.

Installation Overview

Accessing a parking heater’s water pump typically means locating the heater unit itself, which is usually mounted somewhere in the engine bay, under the vehicle, or in a dedicated compartment depending on the vehicle and installation. The coolant circuit local to the heater is drained or clamped off, the pump’s electrical connector and coolant hose fittings are disconnected, and the U4847 12V is installed in its place. Because parking heaters are electronically controlled units with their own diagnostic system, it’s worth clearing any stored fault codes on the heater’s control module after the repair and running a test cycle to confirm normal operation before considering the job done.

Quality & Manufacturing Standards

Webasto is a German manufacturer founded in 1901 and a leading original-equipment supplier of vehicle parking heaters and auxiliary heating systems, used across passenger cars, campers, trucks, and marine applications.

Parking heaters (also called auxiliary heaters) are a common factory or dealer-installed option in colder climates and on vehicles like campers, trucks, and buses, where warming the cabin or pre-heating the engine without idling saves fuel and reduces cold-start wear. Because these units run their own independent combustion and coolant circulation cycle, their internal components — including the water pump and glow plug — are purpose-built for the heater rather than shared with the vehicle’s main engine parts.

Shipping & Delivery

This part ships from our US warehouse network to all 50 states. Order processing and transit times are listed on our shipping policy. Every order includes tracking, and our contact team can help if you need it faster for a heater that’s currently out of service.

Support, Warranty & Returns

We stand behind what we sell: review our warranty policy and terms of service before you buy, browse our FAQ page for common fitment and shipping questions, or contact us directly if you have a question this listing doesn’t answer. You can also browse our full parking heater parts selection to compare this part against other options for your unit. Learn more about how we source and vet the parts we carry on our about us page.

Frequently Asked Questions

How do I know which Webasto model I have?

Check the model designation printed directly on the heater unit’s housing, or check your vehicle’s documentation if the heater was factory-installed. Parking heater parts are matched to the specific unit model, not to the vehicle itself.

Is this the correct part for my specific Webasto unit?

Match the part number listed above against your unit’s original part or your vehicle/heater documentation. Given how limited the published specifications are for this part, we’d strongly recommend you contact our team to confirm fitment before ordering.

Can I install this myself?

Parking heater components are more specialized than typical engine parts, and the units are compact and electronically controlled. DIYers comfortable with automotive electrical work and coolant systems can often handle these repairs, but if you’re not familiar with your specific Webasto unit, having a heater specialist handle it reduces the risk of a comeback issue.

How long does shipping take?

See our shipping policy for current delivery timing. We ship to all 50 US states.

What’s your return and warranty policy?

Full terms are posted on our warranty policy page. If a part arrives damaged or doesn’t match your order, contact our team and we’ll help sort out a replacement or return.

Is a core exchange required on this part?

No core exchange is required for this part — it ships as a standalone replacement unit.

Why is there so little specification data on this listing?

This is a genuine limitation of the source data available for this part, not something we’re withholding. If you need dimensional or electrical specifications beyond what’s listed above to confirm fitment, please reach out and we’ll do our best to track them down before you order.

What does “U4847 12V” mean on the box?

That’s the Webasto part number for this exact part — U4847 12V. Use it to cross-reference against your old part or your heater’s documentation to confirm you’re ordering the correct unit.