Viessmann extension kit for a mixing valve circuit (KM-BUS, Vitotronic 200)

At Q-TECH, we apply the same clear rules for everyone: the law protects you, and when applied correctly, it protects us as well. By processing your purchase, you accept our General Terms and Conditions of Sale. If you are purchasing as a consumer (B2C), nothing stated herein limits the rights granted to you by mandatory law (RDL 1/2007, TRLGDCU): the 3-year legal warranty of conformity and the right of withdrawal under the terms and with the exceptions legally provided, which are detailed below. References to "B2B" apply only to businesses and professionals.

Your guarantees

• Rights intact: 14 days of withdrawal from receipt for most products—subject to the legal exceptions you will see below, such as goods made to your specifications—and a 3-year legal warranty of conformity, under the terms of the TRLGDCU.
• Conformity with the description: we guarantee that the equipment will correspond to the published technical description and what one could reasonably expect from it (arts. 115 et seq. TRLGDCU). Images and videos are for guidance only: the manufacturer may supply a more recent revision of the product or introduce minor aesthetic, packaging, or firmware changes, without this constituting a lack of conformity as long as the described characteristics and performance are maintained.
• Traceability that also protects you: we document the condition, serial number, and seal of each piece of equipment upon shipment, and we video-record the opening of returns; this is your proof of the condition in which the goods were delivered.

Responsible use and your part

• If you are thinking of returning it, keep it as you received it: without installing or activating it, with its seals, accessories, and packaging intact. This is how to ensure a full refund, without deductions.
• Handling that exceeds inspection reduces value: handling the equipment beyond what is necessary to verify its nature and operation may result in a real, assessed, and case-by-case justified deduction (art. 108.2 TRLGDCU), never a fixed percentage. In particular: activating or registering the serial number, linking it to a manufacturer's account or app, circulating water through hydraulic equipment, unsealing probes, or installing software or consumables. Initial inspection of the product does not lead to a deduction.
• The same item must be returned: withdrawal requires returning the supplied unit. Different equipment, or equipment with prior use, age, or wear prior to purchase, does not constitute a valid withdrawal.
• Installation and cybersecurity, shared responsibility: this is technical hardware; you are responsible for correct installation, credentials, patches, and backups, while we deliver a compliant product. Q-TECH is not liable for damages resulting from poor installation, incorrect configuration, or omission of patches by the customer or third parties (in B2C, without prejudice to the legal warranty and liability for intent or negligence, arts. 86 and 130 TRLGDCU).
• Delivery of bulky goods: delivery is made to the curb. B2C: transport risk is ours until physical delivery (art. 66 ter); we recommend noting visible damages on the delivery note and notifying us of breakages within 24-48 hours with photographs to activate the insurance. B2B: inspection and notation on the delivery note are mandatory; hidden damages must be reported within 24 hours (art. 366 CCom). Unjustified rejection or incorrect shipping information will entail the actual outbound and return costs (approx. €85-550 for heavy machinery).

Made to your measure (Advanced Pre-Assembly)

• If your order includes equipment, racks, hydraulic assemblies, or technical rooms made or configured according to your specifications (permanent joints, custom cuts or wiring, parameterization, pressure testing), these are custom goods without the right of withdrawal from the conclusion of the contract (art. 103.c TRLGDCU; CJEU Case C-529/19), which is informed before purchasing and documented in the signed Order Note. A test you request without permanent modification retains your right of withdrawal, with only the actual loss of value caused by that test being deducted. Would you prefer to receive it tested, configured, and ready to connect, without assuming these risks? Contract our Advanced Pre-Assembly or the prior technical audit.

If you are purchasing as a business or professional (B2B)

• The transaction is governed by the Commercial Code: firm sale, without the right of withdrawal; notification of defects within 4 days (apparent) / 30 days (hidden), arts. 336 and 342. Q-TECH acts as a distributor and excludes indirect damages, loss of profit, and data loss, limited to the price of the equipment, without prejudice to the manufacturer's commercial warranty.

Product warnings v1.0 · June 2026. Information summary; the complete and binding conditions are those published at q-tech.es.