Which AlorAir dehumidifiers does this socket fit?

It fits the Storm LGR Extreme, Storm Pro, Storm Ultra, Storm Elite, Storm DP and Storm SLGR 1250x. Check your model plate before ordering, since other AlorAir lines use different parts.

Is this the whole power cord or just the socket?

It is the power socket, the connector the cord plugs into on the unit. The cord and plug are separate.

Can I install it myself?

It is a repair part that goes inside the unit, so it calls for opening the housing and working with the wiring. If you are not comfortable with that, have a technician fit it.

Do I need to match the part to my Storm model?

Yes. Confirm your exact model from the label on the unit before ordering, because the Storm range spans several sizes and generations.

Will this fix a dehumidifier that will not power on?

Only if the socket itself is the fault, such as a cracked housing or loose contacts. A unit that stays dead with a sound socket likely has another problem.