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What model aquastat? If it's an L8124***, then that aquastat maintains Low limit, and only will run towards High limit with a heat demand. So if you're raising the High to 180°, raise the Low to 160°. Differential 10° unless you really want to get into it. Be careful at the faucets.

If the aquastat is an L8041B or equivalent, that aquastat maintains High limit, but I would bring the Low up to 145° considering a pre set 10° differential.

Again, faucet adjustments will be different. Is there a mixing valve?

Welcome new steam homeowner. We were all in your shoes at one point.

Do yourself a favor and cut the lines to the coil, buy a standalone water heater and leave your boiler off in the summer.

There's no reason to tie your domestic hot water to that boiler.

Even a resistive electric water heater is only a few hundred dollars a year to run and if you want, you can get a heat pump water heater and have super cheap hot water with possible incentives from your local utility or state.

As EPaul alludes, the boiler coils are not very efficient, are difficult to control and often clog with lime in many areas. You'll probably be happier with an indirect hot water tank, or separate tank hot water heater.

If you keep the hot water coil, it should (must) be plumbed with an automatic tempering valve to prevent it from delivering dangerously hot domestic water when the heating system is steaming. Many installers skipped the tempering valves or substituted a manual valve to save a few bucks. Especially with kids or elderly folks in the home, overheated hot water can cause serious injuries.

under that cardboard are 3 screws, common, normally open, normally closed,

a volt meter across common, and NO, or NC, would tell you where your volts are going, listening closely will swinging the setting dial you should also hear a click,

Yes. Sorry, I feel dumb assuming you had a closed hydronic system. 180° should be fine and the differential is at 5° so there shouldn't be an issue. Can you show the coil or water heater and piping? Is there a mixing valve?

um, yeah, but you're already set up around 180, (were) correct?

post a picture showing your sightglass, and the domestic coil and aquastat all in one,

water level in the boiler needs to cover the coil for good performance, let's see it

Not dumb at all. Just need a bit more information. The aquastat is exactly what is required and you already have it. You have set it to 180°F and that will solve your problem. You can also see a small white dial on the right side near the bottom. It's set at 5°F. Increase this value to 15°F. This will prevent too much cycling of the boiler when the heat is not calling. I'm fairly sure you'll still be OK in the shower………….but, if not………….reduce it to 10°F.

Don't bother with any meters testing anything under the cardboard………..more work that you don't need.

You already have the anti-scald valve which is important with a steam boiler held at 180°F.

Your boiler is steam so the L4006A is a low limit to run the boiler for domestic water. That is its only purpose. 130 is way to low. Set it at 160 and see how you do. If not enough hw you can go to 170.

If your water is hot when set to 160 after a few days you can creep it down a little till your short of hot water. Play with it until you get the right setting.

Your mixing valve could also be bad or tired. You can also replace the element in the mixing valve if the water temp adjustment doesn't fix it.

The L4006A is working as a low limit. It fires the burner if the water temp drops below the setting.