My water heater is on the patio, hot water takes forever to heat-fix?

Wrap it with a hot water heater blanket.

noodle the hot water pipes...that’s adding a foam sleeve over them. The foam sleeve looks like a grey pool noodle. It has a slit on one side to make it easier to get on the pipe.

Get a good water heater wrap and take a weekend and build a box for it. Then cover your pipes.

If water heater is electric & has 2 elements, one of them may have burned out. If that's the case, it will take a long time for water to heat. Even single element water heaters can have the element become so mineral coated from your water that it will not heat efficiently, yet it will still work, just not very well. Replacement elements are much less expense than replacing tank.

Insulation of the water heater & it's water lines will certainly help it to work better, not to mention use less energy.

Hope this might help.

Have a plumber install a recirculating pump that can be either temp. controlled or a switch you can turn on about 5 min. before you need hot water.

its out there for a reason, with that said,,if possible raise it up 5 inches on a piece of plywood,,insulate under it,,,wrap any exposed pipes, put a hot water insulating blanket around it, then build a insulated box around it..Leave a few small holes at the bottom / top so as air can circulate around it as well. any handy man/neighbor can do this

Move it inside