Electrical appliances damaged due to repair in an apartment

I own a rental unit that I rent to a couple. I notified them [both in writing via WhatsApp and verbally] two days in advance, that I am installing an electricity meter in their apartment [of course, with a licensed electrician] and the electricity will be disconnected for about an hour and they should be prepared for the repair. Apparently, the turning on and off of the electricity several times damaged their old refrigerator and a water fixture [an old filter that was installed in their apartment that morning] and since then these products have been malfunctioning. I would like to ask the Rabbi, if I am obligated to repair the electrical products that were damaged. According to my understanding they should have unplugged all the electrical products in their apartment. It's true that I didn't tell them this, but even the electric company that compensates for problems in the electrical system, does not provide monetary compensation for problems caused by disconnection and return of electricity [sudden and not initiated power outages like in my case]. In addition, it is reasonable to assume that the products that broke down were nearing the end of their useful life. The proof of this is that other sensitive electronic equipment like the air conditioner [a new air conditioner that belongs to me] or their stereo system did not break down.

Greetings,
Our teacher Rabbi Fried ruled that the landlord should not be obligated to pay, but should compromise with the tenants.