Replace old video door phone: count the cores first

The handset is dead, the cable is still in the wall, and a listing has already promised that you can replace an old video door phone with whatever is in the basket. The buy is the number of intact copper cores. Products Compared set amazon.co.uk listings for wired video door phones beside that cable problem on 15 October 2026, including the EZVIZ CP5, the TMEZON MZ-V20 and the QingTianTongYun V168M4. We ran no lab test, and we did not pull your cable. A qualifying amazon.co.uk purchase can earn us a commission at no extra cost to you.

Prices and review counts from those listings are on the video door intercom comparison.

In short

Count intact cores before you order. Two cores suit the EZVIZ CP5, with power through the cable, listed at £161.49. Four cores suit the TMEZON MZ-V20 or, on a long run, the V168M4, both listed at £79.99, and you supply the cable. With no usable cable, buy a wireless kit. A communal entrance or a fire-door strike is an installer, and the strike itself is absent from these boxes.

Count the cores before you replace an old video door phone

Look at the back of the dead handset, or at the outdoor station if the indoor end is only a junction block. Count copper conductors, not the ridges on the sheath and not a diagram printed when the phone was new. Intact means the conductor still runs from the door to the room where the monitor will sit. Two broken strands inside a four-core sheath leave you with two wires. Old intercom wires that have gone green, or that vanish into a soft chocolate-block, are out of the count.

Label the door end and the room end with tape before you separate anything, and photograph the cores. If you use a simple continuity tester on this extra-low-voltage cable, a core that does not ring through counts as missing.

Stop at one kit family: two intact cores, four intact cores, or no usable cable. A cable that disappears into a landlord's riser, a fire-alarm panel, or a neighbour's flat is outside those piles. Leave it connected and speak to the managing agent. The core count on a shared entrance is not an order form.

A 2 wire video intercom is the two-core buy

Two intact cores are the EZVIZ CP5 case. On amazon.co.uk on 15 October 2026 the CP5 was £161.49, rated 4.4 from 1,330 reviews. The listing supports a 2-wire install and also says a 4-wire system is compatible. Power is through the cable. It is the top pick when you replace a door phone with video and the wall only has a pair.

The indoor unit is a 7 inch colour touch screen. The camera is listed as 1080p across 134°, with infrared stated at about 5 metres. You unlock from the monitor, the EZVIZ app, or two RFID tags. Clips go to a microSD card of up to 512 GB or to EZVIZ CloudPlay, and a card is not stated as included. The app needs Wi-Fi and an account. The indoor screen still answers if the router is off, as set out on the no-Wi-Fi subpage. A UK review says you need two wires indoors, ideally a twisted pair, and that the listing had no wiring diagram. The linking cable is not included, the parts field reads 36 EU, and weatherproof is claimed with no IP code.

Four-wire on the CP5 means that door phone can land on two conductors or on four. The TMEZON is a 4-wire bus that expects four cores. A confirmed two-wire flat stays on the CP5. If you cannot see both ends, leave the order until you can.

A 4 wire door entry kit needs four intact cores

Four intact cores are the TMEZON MZ-V20, the best value in this set at £79.99 with 4.2 from 416 reviews. It is a 7 inch monitor on a 4-wire bus, with no app and no Wi-Fi account. The outdoor unit is IP65, power is listed as 12 V corded, and you unlock from the monitor. The extension cable is not in the box. A 4-pin connector takes a cable you provide, which is the old run when every core is intact. A UK review returned one because it does not connect to a phone, despite a Smartphone line in the listing. The dimensions field of 25 × 25 × 25 mm does not describe a 7 inch screen.

The QingTianTongYun V168M4 is the other four-core kit at the same £79.99: a 4.3 inch screen, 4.0 from 34 reviews, and a stated run of up to 100 metres. 700TVL is not 1080p. The parts list names a UK 3-pin adapter, the monitor and the camera, while bullet 5 says the lock, the exit button and the power supply are not included. Check the adapter is in the box before you pick the smaller screen for a long run.

The single TMEZON omits the extension. The two-monitor pack, MZ-V20 2-pack plus MZ-A2, was £135.99 with 4.1 from 153 reviews and includes a 1 metre test cable plus two power supplies. The extra £56 buys a second room, and each screen needs a socket. Cores that fail in the cavity put you back on two wires, or on no cable at all.

No usable cable is a wireless kit

Corroded cores, a cable that fails from end to end, or a sheath with nothing left inside it are a wireless buy. The wired and wireless comparison is the page for that fork, and the wireless video door intercom comparison holds the battery kits. The old pair stays in the wall.

The ACEBELL in these listings is a 7 inch kit at £189.99, rated 4.4 from 74 reviews. The outdoor cell is listed at about 45 to 60 days, and an owner review describes about two days, so the long figure stays a listing claim. You can hard-wire that outdoor unit at 12–24 V. That feed powers the outdoor unit. It is not the TMEZON four-wire bus. The listing also says to keep the outdoor unit off a metal door. The XPJ TL-WF701, at £207.99 with 4.4 from 31 reviews, follows the same battery pattern, and the listing tells you to keep the indoor screen on charge.

A new four-core cable, pulled in your own home without opening a fire compartment, puts you back on the TMEZON at £79.99. With no route for a new cable, stop reading bus specifications.

The old unlock, a communal door, and where you stop

The old handset unlocked the door because it closed a contact onto a strike already in the frame. The new listings sell a release command. On the V168M4, bullet 5 says the electric lock and the exit button are not included. On the TMEZON, the parts field lists the monitor. On the CP5, you unlock from the monitor, the EZVIZ app, or the two RFID tags. None of those lines puts a strike or a fire-door retainer in the carton.

On your own front door, match the monitor's release terminal to that strike using the diagrams that came with both parts. This page does not print wire colours. If those diagrams are missing, the unlock waits. The how to install page is the outline for a normal house door on your own cable.

A communal block entrance is a different door. The cable may serve other flats, and the leaf may be a fire door. That swap belongs to an installer and the managing agent. New 230 V work, a transformer on a new circuit, or a fire-door lock is where England's Approved Document P applies to electrical work in dwellings.