How to replace the broken intercom in an old apartment? Judgment Guide for Indoor Units, Community Systems and Weak Current Pipelines

If the intercom is faulty, don’t rush to buy a replacement one online

Common indoor intercoms in old apartments are yellowing, noisy, and the buttons are malfunctioning, which makes people think that buying a new machine and plugging it in is enough. In fact, the intercom system may be a single-family doorbell, a shared door phone for the entire building, a management room connection, or a multi-line system with imaging and access control functions. Indoor units that look similar in appearance may have completely different wiring sequences, power supply methods, and communication protocols. If they are connected incorrectly, they will not only be unable to make calls, but may also affect other residents.

First clarify which section you want to repair

You can start with the simplest situation: after pressing the door button, is there a ringing sound in the room? Is there any noise when you pick up the phone? Is it just my house that cannot be used, or is the entire building abnormal? If it is a residential complex, first ask the management office or management committee if other households have reported the same problem recently. Single-household failures are common in indoor units, buttons, and line contacts; failures in the entire building may involve shared door stations, power supplies, or hosts, which cannot be replaced by a single household.

Taking photos to record is more reliable than finding the model from memory

Before disassembly, take pictures of the front and back labels, terminal arrangement and original wiring position of the indoor unit, and confirm whether there is an image, door open button, alarm or management room call function. Don't cut the wire short or pull it out without marking it just because you want to repaint it. Weak wires in old houses often run inside the wall or next to the door frame. Once broken, repairing it may be more troublesome than replacing the machine.

Three reasonable paths when updating

If the system is still normal and there is a compatible original or replacement indoor unit, partial replacement is usually the most trouble-free. If the lines are aging but the pipelines are usable, you can evaluate and replace the wires and indoor units. If the entire equipment is old, parts have been discontinued, or video access control is required, the host, door station, resident terminal, and management terminal need to be planned based on the community. It is not appropriate to rely solely on the needs of a single household. Before building construction, an application should be made in accordance with the management regulations, and the construction scope, cooperation methods of each household, and future warranty should be clearly stated.

The quotation should look at the "system scope" rather than just how much one unit costs

It is required to list the equipment model, the number of indoor units, whether the door station or main unit is included, whether the existing lines are used, how to handle the door lock control, testing and warranty content. If the access control will be temporarily disabled during the replacement period, alternative access methods should also be arranged in advance. Walkie-talkies are inconspicuous but important weak-current equipment every day; clarifying the compatibility and common rights and responsibilities first will save money than buying a cheap machine that cannot be installed.

Imaging, access control and mobile phone notifications are not required

Before upgrading the system, first confirm whether what the community really needs is seeing visitors, opening doors remotely, recording at night, or simply restoring stable calls. The more functions there are, the more host, network, storage and maintenance issues there are. When it comes to resident images and access records, a clear management method is needed. For small apartments, easy maintenance, predictable behavior after a power outage, and being used by all residents are often more important than being packed with features. Keeping meeting minutes and equipment documents when making decisions can also avoid being unable to take over when the chairperson changes in the future.

Keep the original wiring information

Even if only one indoor unit is replaced, the terminal label, wire color, model and construction date should be left in a place where the household or management unit can obtain it. When a fault occurs in the future, maintenance personnel can first determine whether it is a problem with the equipment, wiring, or common end, without having to rely on guesswork to tear down the wall. If the system has stopped supplying parts, instead of constantly buying replacements from unknown sources, it is better for the community to discuss the timetable and budget for a complete replacement. Although this is inconspicuous, it can really come in handy for access control and visitor communication when needed.

Keep a record of the current situation before and after construction begins

Before starting any home equipment or decoration adjustment, take photos of the panorama, joints, corners and original equipment markings; after completion, record the test methods, abnormal sounds, material models and warranty contact information. This information is not intended to predict the occurrence of disputes, but to allow the next person to understand the original condition when repairing, subletting, selling or handing over the property in the future. When a problem is discovered, you should first stop using it in a way that may cause damage, and avoid dismantling and modifying unfamiliar water, electricity, gas or wall structures in a hurry. By keeping good records, repairs will be judged faster and expenditures will be more easily explained.