Mix of Copper and Old Aluminum Wiring in Flat—What Are My Options as New Owner?

Question

I have a problem with the electrical installation in my flat. Well, when I tried to replace the sockets, it turned out that the cables sticking out in the box are replaced (copper), while outside the box in the wall are old aluminium cables, connected by a cube. At first glance the old cables...

Bogdanor · Answer

You are absolutely right. You have to replace the entire installation (at least the part that is made of aluminum, and looking at what the previous owner did, it will probably be the whole thing). aluminum oxidizes very quickly. First of all, if you can't do the whole thing right away, do at least the part where the sockets will be most loaded, and pay attention to how the installation looks like, e.g. in the bathroom and other wet places, see also if the sockets are zeroed or grounded (is there a bridge to the pin) from the zero wire or also goes to the pin, a separate wire)

polcia · Answer

thanks for the advice, I'll check the cubes and connections. I would like to pursue this previous owner for fraud, but he only verbally informed me about the replacement of the installation, I do not have it in writing. Do I have any chances for, for example, a reimbursement of the installation replacement costs, maybe someone had a similar situation, please contact me.

_jta_ · Answer

And what are you able to prove to him? If nothing, you will get something only if his conscience moves him ...

lechm56 · Answer

Moved from Other.

Popak · Answer

Hello

I do not know what the situation was, but I also encountered a situation that the owner had broken ends of the aluminum wires and replaced the part with a copper one (as the author describes)

Regards

Jack14 · Answer

I will join:
I also had such a situation and I consider what my colleague above recommends "ripping" the entire installation redundant.
I left all the sockets on the aluminum except for the washing machine and dishwasher, and I live to this day.

ps

moreover, like most people living in blocks built during the communist era ("skyscrapers" made of large slabs)
Replacing the installation in the whole apartment will not help at all because the electrical installations in the risers remain aluminum anyway.
(Unless it's a new free-standing house)

Regards

ekwador · Answer

If the aluminum conductors are healthy (they are not oxidized, the insulation is not damaged by temperature, they do not break) then I would leave it. There is no point in replacing it, unless you carry out a major renovation, then replace it as much as possible. I am often surprised by people who install tiles in, for example, bathrooms and leave old aluminum wires Sometimes the walls are so crooked that you don't need to hammer anything because the wires will hide under the leveling mortar.

_jta_ · Answer

Thick aluminum conductors when properly bonded (so that they do not come into contact with anything containing copper
- because even traces of copper corrode aluminum), they are not a problem; prone to damage are thin, and with
in contact with copper. I have already burned a few sockets - aluminum corrosion, resistance increases -> smoke from burning insulation.
Unfortunately, it is not easy to replace it: the wires are not in tubes, but embedded in them - you would have to hammer the wall to put new ones.

ekwador · Answer

Think about what you wrote ... Aluminum must not corrode Because it immediately becomes covered with an oxide layer, which protects the metal against corrosion Another nonsense is that Al will corrode on contact with Cu And your sockets burned because you joined two metals of different hardness. Al deformed and the contact loosened, causing excessive heating.

_jta_ · Answer

Certain metals - I know about copper, mercury, and gallium - render corrosion protection ineffective
an oxide layer covering aluminum (they taught about copper at school, about gallium in Tołłoczka's book
- it has a great effect, aluminum reacts with water as vigorously as sodium, mercury also has nice effects).
For this reason, special Kupal spacers are used to connect aluminum with copper.

ekwador · Answer

Such spacers are used outside (overhead lines) where Al and Cu are exposed to water. In the absence of a washer on the connection of these metals, a kind of a link is created and the contact loses its parameters.

atlantel · Answer

Hello! My friend, Ecuador, also in closed rooms, aluminum cannot be directly joined with copper, and every electrician knows about it. Regards

ekwador · Answer

Every electrician knows, and I've seen such flowers that my hands drop .

CISU · Answer

Cramp, normally a man learns all his life :-)

Honestly, it would not even occur to me to make such makeshift aluminum and copper.
How to replace it all :-)

well, although it is not always possible :-)

But an interesting post :-)

I will have this in mind when buying a flat :-)

marcino2000 · Answer

I heard about such cases that an electrician came to replace the installation, took kasiore for material, sculpted everything in the way described here and disappeared.

As for Al-Cu joints, this should not be done because electrolytic corrosion occurs, enough air humidity to damage the joint after a short time.

So if I was the owner of such an aluminum-copper sculpture (and also connected at the ankles, in places not intended for it), I would definitely replace it as soon as possible. You probably know your friends, this textbook example about a washing machine, a broken eNie and a woman how the phase hits the casing ??

_jta_ · Answer

I would suggest checking what these cubes are made of: is that piece of metal that connects them,
and with which the wires are in contact, is it bare brass (contains copper) or is it nickel-plated?
The difference is easy to see: brass is yellow, nickel white. And from brass, aluminum corrodes ...

nostromo · Answer

>>4246611 In many old blocks of flats, the old wiring in the riser (aluminium with cotton insulation) is replaced by the administration with new cables with normal earthing. The flat owner has to replace the installation in the flat at his own expense. Combining aluminium with copper is not a very good idea (special adapters are available). If the landlord does not want to replace the installation, but only to patch it up, I require him to sign a statement that he has been informed of the consequences of not replacing the old two-wire installation (aluminium with cotton braid) with a new three-wire copper installation. Obviously, only in cases where a new installation is pulled in the cages in the riser.

Mix of Copper and Old Aluminum Wiring in Flat—What Are My Options as New Owner?

Post #1

Post #2

Post #3

Post #4

Post #5

Post #6

Post #7

Post #8

Post #9

Post #10

Post #11

Post #12

Post #13

Post #14

Post #15

Post #16

Post #17

Post #18

Topic summary