UK Doorbell chime wiring

[Richard Cook]

Hi folks

I moved into our house a year ago and at some point I disconnected our doorbell chime and then, stupidly, managed to chuck it in the chaos of life.

I normally take a photo before I disconnect anything but didn’t this time and all I have is the photo attached of 4 white wires.

Does anyone know how to wire up a new chime? Is it trial and error or is there a system to which white wire goes to what on a new chime?

Also is there a way to check if these wires are connected to a transformer and thus use the wires at the doorbell to upgrade to a more modern doorbell (Ring, or similar?).

Thanks so much.
Rich

 

[Richard Cook]

After further investigation I found the transformer next to the consumer unit.

 

[i=p/u]

12v to door, 12v back and join on to feed chime, negative at chime aswell. Maybe?

 

[littlespark]

Have you got a multimeter and a steady pair of hands?

assuming the transformer is not powered, one of the pairs will give continuity when you hold the probes against the bare ends and have someone else push the doorbell button.

 

[telectrix]

just buy a wireless bell kit.

 

[Richard Cook]

Thanks for the replies.

I’ve done the following (see photo) as well as switch the wires around on 0 and T3 and pressing the doorbell does nothing on both occasions. Hmm.

 

[Avo Mk8]

Are you sure the bell push goes to 0F and 1, and the transformer goes to TF and 1?
If you touch a wire between 0F and 1, does it work? if not, something up with the transformer or its wiring.

You really need a multimeter to check which wire is which!

 

[Richard Cook]

Thanks for the reply!

I have a multimeter I’ve just never used one so unsure what to do?

 

[Richard Cook]

And this is a photo of the instructions from the bell. The second option has 4 wires; two from bell push and two from transformer. Two wires were already twisted together so assumed one was from bell push and one from transformer.

 

[Avo Mk8]

And this is a photo of the instructions from the bell. The second option has 4 wires; two from bell push and two from transformer. Two wires were already twisted together so assumed one was from bell push and one from transformer.

I think that's a fair assumption.

if your multimeter has batteries, check the thing still works!
Set it to an AC volts range, say 20v or whatever similar option you have on the selector switch.
Put one probe on the wires twisted together (terminal 1), and the other on terminal T3. In an ideal world you should get a 12v approx reading. If you don't, try terminal 0.
if no reading, visit the transformer, and taking note of post 4, and keeping well away from mains connections, check for 12v on the choc block at the top.
if no voltage, disconnect T3 wire at the chime, buy some batteries and put them in the chime ?

mind you, there's one other possibility that the output of the transformer is actually the two wires twisted together, in which case the transformer is probably US by now!

 

[Richard Cook]

Thanks again so much for the help.

Attached is a photo of my multimeter. I’ve set it to AC volts and probed T1 with T3 and got 16v and then did the same with T1 and T0 and got 16.80v.

I went to the transformer and did the same and got around 16.78v.

 

[Avo Mk8]

That's great that you have volts at the chime.

It's possible that the wires to 0 and T3 are the wrong way round,
if you get a short piece of wire and quickly dab terminals 0 and 1 together, does it chime?
if you get a spark instead, the 0 and T3 wires are almost certainly the wrong way round.

16 volts is a bit higher than I expected, though the transformer is off load. Vaguely possible there's something odd going on. Let us know how you get on!

 

[Avo Mk8]

Another couple of tests if things are still not working. Preferably turn the mains to the transformer off for this.
Set the multimeter to the ohms range, and measure the resistance between terminals 0 and T3. This should be the chime solenoid resistance.
Also, as per post 4, and if there's someone there to help, on ohms range, measure between 0 and 1 while somebody holds the bell push down. Should be a low resistance that goes away when you release the bell push (unless there's a light bulb in the bell push in which case you get a higher resistance)!

 

[Richard Cook]

It's possible that the wires to 0 and T3 are the wrong way round,
if you get a short piece of wire and quickly dab terminals 0 and 1 together, does it chime?
if you get a spark instead, the 0 and T3 wires are almost certainly the wrong way round.

Okay! So! I think we're getting somewhere.

I quickly dabbed terminals 0 and 1 together and it did chime (!!!) but also got a wee spark.

Should I try and swap 0 and T3 around and see if it chimes with no spark?

 

[Richard Cook]

I went out and looked at the bell push. Think it's knackered. I removed from the wall and used a length of wire to touch the two wires and it rang the bell! I think the terminals on the bell push are corroded so have ordered a new bell push and, fingers crossed, that should be that.

I really appreciate all the help you've given.