When the neutral wire goes to the switch
I assume you are hard wiring it and not plugging it in. The power coming into the GFCI outlet connects to the line side of the GFCI outlet. If you want the outdoor timer protected by the GFCI then connect the wire going to the timer to the load side of the outlet. If you do not want the timer protected then connect it to the line side. On the back of the GFCI if you look closely you will see Line & Load marked on the back.
If you are adding the pull chain to an existing fixture then the pull chain switch should have two wires. Wire nut either one to the hot wire coming in and the other to the black wire of the fixture.
Wire is the transition material used to carry the electric current; the switch is the controller of that current.
The two wires which connect the timer switch on a Century 87423 battery charger are the red and black wires. The red goes to the positive connector while the black goes to the negative connector.
First you need to decide what you are trying to accomplish. You can wire the Timer switch in series with or parallel to the 3-way switches. If in series then the 3-way switch function would depend on the timer state. If the Timer switch was ON then the 3-way switch could turn the connected device ON or OFF from either location. If the Timer switch were OFF the device would be OFF no matter what you did with 3-way switches. To wire in this fashion put the timer between the supply and the input to the switches. If the Timer is in parallel then if the Timer is ON it doesn't matter what you do with the 3-way switch, the device will be ON as long as the Timer is ON. If the Timer is OFF then the 3-way switches will work in their normal fashion. To wire in parallel connect the supply to one side of the Timer and the device to the other.
The clock timer on your immersion heater is for you to program the heater to run at certain temperatures at certain times. You can contact your utility company and ask what the off peak or low demand hours are. Those times it is less costly to run your heater.
There are many places where one could buy a timer to control a light switch. One looking for a timer to control a light switch should visit popular on the web sources such as Lowe's, Intermatic, and Honeywell Store.
Wiring a T101 timer is easy. All you have to do is color code the wiring into the input sections.
If it is a 2-wire switch- yes If it is a 3-wire switch- no
Not usually, The light would have had to been wired with a three wire from the switch to the fan. One circuit to control the fan and the other switch to control the light. If this is your situation then all you will have to do is change the light switch to a timer and that will do what you want.
House wire is "line" Black & White house goes to Black & White of Timer; the "load" (e.g. Pond Pump, etc.) is connected to the Red & White. Specifically, put all 3 whites together (nut or terminal); House (source)(line) Black to Timer Black; and "load" Black to Timer Red. The Red wire is the "Timed" (switched) hot wire.
Wire the switch to the hot/black lead.
You have a 3 way switch. Your black wire is the hot wire. Your green wire is the ground wire. Your red and white wires go to the light and other switch. You should have gotten a wiring diagram with your switch.
Immersion heaters are used for heating water in a hot water tank. Immersion heaters are usually controlled by thermostat and they will heat your water to a set temperature for as long as you leave it on that setting, or you can have a timer set. It is usually an expensive way to heat water compared to central heating systems with hot water circuits.
A switch is inserted in series with a single wire. When the switch is on, it is as if the wire had not been opened to insert the switch. When the switch is off the wire is open and no current can flow. All a double pole switch does is allows you to switch two separate wires at the same time with the same switch action. A single pole switch just switches one wire.
with a standard 1 pole light switch (one switch operating the light) it is black wire to black wire and white to white (non grounded)