Heater Hose Connector – 3B0 122 291B (URO)

Description

The 3B0 122 291B Heater Hose Connector by URO Parts is an OE-style fitting for the secondary heater system. Specifically, it connects the heater hose to the engine at the heater core inlet, providing the sealed junction that allows coolant to circulate through the cabin heating circuit. Furthermore, URO manufactures this connector from PA66-GF30 glass-filled nylon — the same high-strength, heat-resistant polymer used in the original OEM component — so it maintains its dimensional stability under sustained coolant temperatures. Because the 3B0 122 291B is a straight-through, single-outlet design, it is distinct from the suffix C and K variants, which have different outlet configurations. Therefore, always confirm that your vehicle specifies the B suffix by VIN before ordering, since using an incorrect outlet configuration will prevent proper hose routing and sealing.

Over time, the original plastic body of the 3B0 122 291B Heater Hose Connector weakens from repeated heat cycles in the heater circuit. In particular, the secondary heater system operates at full coolant temperature whenever the cabin heater runs, so the connector body endures consistent thermal stress at the heater-to-engine junction. Consequently, the PA66 plastic can develop hairline cracks at the hose barb or along the body walls. Additionally, the OEM clip engagement groove can wear, allowing the hose to back off the connector under system pressure. As a result, coolant seeps at the heater inlet junction, leading to gradual coolant loss, recurring low-coolant warnings, and reduced heater output. Therefore, replacing the failing 3B0 122 291B promptly restores a secure, sealed heater circuit connection and recovers full cabin heating performance.

Signs Your Heater Hose Connector Needs Replacing

Catching a failing 3B0 122 291B early prevents worsening coolant loss and heater performance issues. Therefore, watch for these warning signs:

• Coolant seeping or leaving dried residue at the heater hose junction near the firewall or engine inlet

• Recurring low coolant level warnings despite topping off the reservoir, with no obvious external leak elsewhere

• A sweet coolant odor inside the cabin or from the firewall area after the heater runs at full temperature

• Visible cracking, crazing, or whitening of the plastic connector body at the hose barb or clip groove

• The heater hose feeling loose at the connector or pulling back from the engagement clip under light hand pressure

• Reduced heater output or intermittent warm air, suggesting restricted coolant flow through the heater core inlet

If any of these symptoms appear, replace the 3B0 122 291B without delay. Additionally, inspect all adjacent heater hose quick-disconnect connectors at the same service interval, since they share the same heat and pressure exposure.

3B0 122 291B Heater Hose Connector — Key Features

• OEM Reference: 3B0 122 291B (URO Parts OE-style aftermarket — URO-008161)

• Secondary heater system hose connector — heater-to-engine/heater core inlet position

• Straight-through, single-outlet design — does not replace suffix C or K variants

• Molded from PA66-GF30 glass-filled nylon for heat resistance and dimensional stability

• OEM clip attachment method — snap-fit engagement compatible with factory hose clamps

• Broad VAG platform compatibility — VW Golf, Jetta, Beetle, Rabbit, Eos, CC, Golf R; Audi TT Mk1, A3 8P

• 24-month unlimited mileage warranty from URO Parts

• Cost-effective OE-style alternative to the Genuine VW/Audi dealer connector

• Direct-fit replacement — no modifications required

Service Notes for the 3B0 122 291B Heater Hose Connector

• First, confirm fitment by VIN and verify the B suffix — this connector does not replace 3B0 122 291C or 3B0 122 291K; using an incorrect outlet configuration will prevent proper hose routing

• Next, replace any associated O-rings and hose clamps during installation; never reuse worn sealing hardware on a new connector fitting

• Also, inspect all adjacent heater hose quick-disconnect fittings at the same service interval; replacing aged connectors together prevents a repeat heater circuit visit

• Then, verify the heater hose seats fully into the new connector and the OEM clip engages with a firm click before pressurizing the system

• Finally, refill with VW/Audi-approved G12++/G13 coolant and bleed the cooling system completely to eliminate air pockets before returning the vehicle to service

3B0 122 291B Heater Hose Connector — Compatibility & Applications

Always verify fitment by VIN before ordering. Multiple variants may exist within the same model year.

Cross Reference Numbers

• 3B0 122 291B (VAG OEM reference — URO Parts OE-style replacement)

• 3B0-122-291-B (alternate formatting)

• URO-008161 (URO Parts internal SKU)

• Beck Arnley 147-0062

• Dorman 627-002

• VAICO V10-9858

Additional information