A water heater jacket, also sometimes called a “blanket” is an insulated covering, made specifically for water heaters. The concept is that, by adding an extra layer of insulation to the outside of the water heater, the appliance will lose less heat, and be more energy efficient.
Whether or not a water heater should be covered with a jacket is a very common related concern with homeowners. In fact, many homeowners will ask a plumber that just replaced their water heater, “Shouldn’t that have a blanket”? We will address that issue in this article.
Does my water heater need a jacket?
Years ago, water heaters used to commonly come with an R-8 insulation value. An R-8 value basically means that there is 1” of insulation material between the tank itself, and the outer skin. Blankets were created because having only 1” of insulation allows for too much heat to escape the appliance.
Eventually, manufacturers began to make water heaters that had a rating of R-16. They had 2” of insulation, and were much more efficient. Together with other advances in technology R-16 rated heaters were actually made to be much more efficient than their R-8 counterparts (even with the blankets).
Today, the vast majority of water heaters are built to the R-16 standard. There are still instances where an R-8 might need to be used, but that is usually because of space restrains. In order to have more insulation (an R-16 water heater needs to be either fatter, or taller than an R-8 of the same size), but R-16 rated units are so much more common that they are actually usually less expensive.
The bottom line…
If you have an old water heater that has an R-8 rating, or for some reason had to install a new R-8 unit, you should have a water heater jacket for it.
If you have a new water heater (or even an older one) with an R-16 rating, you do not. If fact, many newer water heaters not only discourage using a blanket on an R-16 heater, but will void your warranty for using one.
If you are not sure what insulation rating your unit has, the rating is usually found on the information sticker on the unit. You can also remove the pilot light cover, and look at the space between the outer skin and the tank. Remember:
1” = R-8 – You need a blanket
2” = R-16 – You do not need a blanket
You could also feel free to ask your local Allstar Plumber, and he would be able to tell you in an instant. A great time to ask is during your free home plumbing inspection. Not sure what that is? Call us today to find out!
