Viking

Yes, if it is one of Viking's dialers. The K-1900-3 apartment entry dialer stores up to 250 tenant phone numbers, one per 1 to 3 digit apartment number, and Viking's manual says it dials the tenant's number and joins them to the entry phone. The C-4000 also stores 250 and, in Viking's words, uses a phone line to call tenants through the public telephone network with the tenant's actual number programmed in. The K-1705-IP and its relatives do the same over a SIP phone service. The single-door E-30 and E-30-IP dial up to five numbers in turn.

Some Viking door phones never dial out on their own. The E-10A, E-20B, E-40 and E-50 hang off a Viking controller or a phone system port, and the C-3000 rings tenant phones over the building's own wiring with no outside line. If buzzing your unit does not make any phone ring, there is nothing to forward. Apartment call boxes explains the difference.

It depends on the model, and every code can be reprogrammed. On the K-1900-3 and the C-4000 the factory relay code is 36, pressed on your own phone during the call. On the K-1705-IP, K-1770-IP and the C-2000B controller the default is ** (star star), and the second relay on the IP panels is *2. On the IP panels Viking accepts the code only from the phone that was called, and # from that phone hangs up.

Calls are short by default: 40 seconds on the C-4000, 2 minutes on the K-1900-3 and 3 minutes on the K-1705-IP and E-30. When a timed key or guest code is active, Enterkey answers and plays the open code for you, so a visitor gets in well inside those limits.

Sources: Viking K-1900-3 Technical Practice (DOD 312, ZF300910 Rev H, October 2024), C-4000 Technical Practice (DOD 164, ZF301760 Rev C), K-1705-IP Series Product Manual (ZF303750 Rev C, October 2025), E-30/E-32 Technical Practice (DOD 212, ZF303490 Rev C) and Viking's C-2000B relay code support article, all checked October 18, 2026. Your building may use a different code; ask for it before you switch, or email support@enterkey.app.

Whoever holds the programming code: usually your property manager or the installer. Viking dialers are programmed from a touch-tone phone, on site or by calling the panel's line, and the IP models from Viking's PC software. Moving your unit to Enterkey changes one memory location, the phone number behind your apartment number. This request template tells them exactly that, and the apartment buzzer guide covers the rest of the setup.

The test is simple: when a visitor buzzes your unit, does your cell phone (or a phone number you chose) ring? If yes, your system dials out, and Enterkey works by giving it a smarter number to dial. If your buzzer only rings a wired handset inside your unit and can't call an outside line, it isn't compatible.

Not sure? Ask your property manager one question: "Can the directory entry for my unit point at any phone number?" If the answer is yes, you're set: see how Enterkey works, and if you get stuck, support@enterkey.app answers within hours.

Ready to ask? This request template is written to be forwarded as is: it tells your manager exactly which field to change and how to undo it.