Today I received my new refrigerator, and I've been told not to plug it in until a couple of hours have gone by. Some people told me a couple of hours was enough, but others have told me up to 12 hours. I understand the reasons as to why do this (although there's probably more to it than what I know).
How long should I really wait? Is there some science into this?
The short answer is to check with the manufacturer. That way you can be sure to stay within warranty guidelines.
The longer answer is that it varies from model to model. When a refrigerator is placed in a non-standard position (for example on its side), compressor oil can run out of the compressor and up refrigerant lines. So if you don't stand it upright and wait, the compressor will pump without sufficient oil -- not good.
Don't plug it in for a couple of hours because the frig may have been laid on its side while enroute to you. Its because the compressor lubrication oil could get into the cylinder of the compressor and if not given plenty of time to drain back into the oil sump at the bottom of the compressor, could cause major compressor valve damage on start up. 2 or more hours is a good rule to observe. See 10's answer above also.
You only have to wait if the refrigerator has been laid on its side at some point during shipping. When laid on its side, the oil in the compressor goes up into the refrigerant lines. If you start the compressor with insufficient oil, it can be damaged. So, the manufacturers recommend 2 hours JUST IN CASE.
If you KNOW that the refrigerator has been transported horizontally, I'd leave it upright for 24 hours just to be 100% sure.
We just bought a new Samsung French Door refrigerator. The manual recommends waiting 2 hours after installation before plugging it in but with no explanation for the wait.
The user manual of an LG GR-151SSF, which I just bought today (second hand) says nothing about waiting before connecting the power supply. Also, the section "IF YOU MOVE" says nothing about waiting before plugging in. I will just do it right now.
The refrigeration unit should sit upright for at least the same number of hours as it was on its side, longer if the oil was exposed to very cold temperatures. I would always set a minimum as well.
Three new fridges in 25 years. Never waited to plug them in; never had a problem. I never even heard of this wait time before.
Short answer straight away, this is a delivery driver trick. I used to deliver fridges we built or repaired.
Please leave it for 4 hours if it has been kept upright. This will extend its life greatly. And a unit should never have been laid on its side. Never.
