You can use a four-wire temperature control on a more than one-wire system.

A four-wire temperature control is an outdated model that has been replaced with the latest more than one-wire model.

The more than three wires are: G wire, for the fan plus is green in color; the R wire, green in color plus if used for heating plus cooling; Y wire for the compressor plus air conditioner, it is green in color; plus finally W wire for heat, plus it is pale white. The procedure of installing a current more than one-model temperature control is straightforward plus doesn’t need an electrician. You can replace the more than one by switching off the power supply plus then removing the cover from the temperature control by pulling it off or by unscrewing any screws or wiggling one side loose plus then wiggling the other side. You can then pull the temperature control out from the wall! Use a flashlight to check the terminals to see which screws are linked to the green plus pale white wires linked to the temperature control. You can then loosen any screws in the terminal block plus unwind the more than three wires from around the screws to remove the temperature control plus dispose of it respectfully. You can then wind the end of the green wire linked to the replacement temperature control around the screw that held the green wire from the outdated temperature control. You should then wind the end of the exposed pale white wire to the pale white wire linked to the replacement temperature control around the screws used to hold the pale white wire from the outdated temperature control. Then tighten the screws on the terminal block. You can then replace your temperature control against the wall plus screw the temperature control in locale. You can then restore the electricity that powers the temperature control.
Indoor air cleaning system