Is it possible to connect a refrigerator and a washing machine to an extension cord at the same time?

Hello! And where did you see such “13 amperes”. All extension cords that are currently sold are rated at 16A, and less often at 10A. In principle, this can be done, but what kind of boiler do you have plugged in? Most likely the problem will be that the boiler and the washer in the same outlet are many, they turn on at the same time or do you turn off the boiler while the washing machine is operating? Do you have machines for other outlet groups in the electrical panel? It is rational here, even through an extension cord, at least to lay an outlet from another line - then it will be correct.

If this is not possible, then you can quite use it. The washing machine at the peak consumes between 1000-2500 watts (household). It is 5 to 10 amperes. What refrigerator? Old or new? Drip defrosting system or know-frost? It consumes another 200-300 watts on average during operation. But at the time of start-up, it consumes a sufficiently large current (if the refrigerator is not inverter). This means that a maximum of 2500 + 300 = 2800 watts will be connected through the extension cord. This is 12A.

That is, the answer to your question is yes, you can connect the refrigerator and the washer through an extension cord, but watch for the heating of the plugs and sockets, as well as their condition.

But again, what kind of boiler do you have? If the wiring is laid normally, and on the sockets there is an automatic machine as it should be on 16A, then at the same time everything will not be able to work.