Should I just call an electrician?

I bought a 50yo house. Copper wiring, 100amps. These are the series of events...

Day 1 - Garage receptable wasnt working (mentioned it to realtor). Everything else including sunroom was working.
Day 2 - I checked again and voila. Garage receptable was working.

From there on, it worked. I had plugged something in about every week or so.

Day 50 (or so) which is cpl days back - Garage receptable didnt work when I went to mow my lawn. It was a new 13amp mower, I was using for the first time.
So I plugged in my sunroom, mowed for about 15-20 mins. and suddenly the mower stops again. obviously I thought the mower went bad. But I find out that the sunrooms receptable (all GFCI) stopped working. Even the other lights in sunroom are not working. Everything inside the house is still good.

I checked the circuit breakers and they are all good.

I have average base electrical knowledge. But I like to DIY. What can I try to do? Theres no hurry as I have alternatives. I dont want to call an electrician and have a "I could have done that myself" moment.

 

First thing you'll need is an inexpensive analog voltmeter.

Is the garage receptacle on the same circuit as the room with GFI protection ?
Is the protection just one GFI receptacle that feeds the rest of the others ?
Did you try resetting the GFI protection ?

In order to troubleshoot the circuit you need to identify everything that is on the same circuit and then find out what's working and what's not. The power goes from the panel to each box in the circuit. You will need to work backwards checking each device for wiring issues.

You have to approach the problem logically. The circuit wiring starts at the panel and then branches out to different devices. Those devices are what need to be checked.

 

Are the wires back stabbed? If so move them to the screws. Backstabs are less reliable and can cause problems such as you describe. Note this suggestion does not apply to GFCI receptacles. They are either side wired or back wired which is different from back stabbed.

 

There are lots of things you can do on your own. You can replace switches and receptacles. You can replace light fixtures. You can string new cables from the service panel (breaker box) to provide power to new locations or to upgrade existing wiring. You can inspect for and repair loose connections including (recommended) in the service panel.

But you need to be familiar with household wiring standards and electrical safety. I think the most often book title mentioned is "Wiring Simplified." Otherwise even Home Depot sells handbooks for the DIYer. When you add new circuits and outlet boxes or add things to an existing box, you need to be aware of "box fill," or items in the box. When selecting a handbook, be aware that U.S. standards are different from Canadian standards.

If you plan to do a lot of wiring or even slighly more complex tasks such as putting in a subpanel, you might want to buy the Canadian Electric Code (manual).

"Backstabbed" connections referred to here are those where you strip the insulation off the end of the wire, poke the wire into a hole in back, and that's it. If the wire does not stay in the hole until you tighten a screw on the outside then that style of connection is superior to use or keep using.

 

Be sure to use a 12 gauge extension cord for the mower.

 

I was using 16guage 82ft, that must have messed something up.

 

That cord is too small for the mower, but it didn't cause the problem you are having. Follow the suggestions already given and you might find your problem.