EcoRenovator - View Single Post - Starting My Hot Water Conservation Project

jeff88 · 08-23-13, 04:17 PM

I picked up a water heater blanket at my local Home Depot today, but before I actually install it, I wanted to double check some things.

It has an R-Value of 10. From what I have read, generally speaking 10/11+ is the best. (OK good, I'm off to a good start). I read that newer models have built-in insulation and so the blanket won't help much, so I should consult my owner's manual or the labels on the tank. I couldn't find it on the tank, but low and behold, the landlord was smart enough to leave the OM in the closet right next to the tank! Yay! The OM specifically says the blanket is "not necessary". It doesn't say I can't install one, but it also says problems are not protected if the blanket causes it. It doesn't specifically say what the R-Value is of the tank. So how do I determine what is "necessary"? I touched the tank and it was neither cold, nor hot, so without an infrared gun, I can't be sure how much heat loss there is (and I really don't want to buy one!). I bought a multimeter yesterday and it just happens to have a temperature probe on it. Maybe I can tape it up to the side of the tank and see what it says. At the same time, that reminded me of a temperature probe we have for another project. Maybe I will do one on two sides. Take a shower and see what happens when the heat starts to really kick in. One caveat, though, is that one wall of the closet is an outdoor wall, so during the winter it might get colder. A caveat to the caveat, however, is that it is west facing, so it will stay warmer than if the outside wall was facing another direction.

My next question is a matter of preferences. Here is what I bought: Frost King Fiberglass R-10
Here is what I found afterwards: Duck Recycled Cotton R-6.7
My question is this: which is better? One is higher value, but is fiberglass (boo!) and the other one is lower value, but is recycled cotton (yay!). Does it really matter which one, or is the 3.3 difference large enough to make a difference? I would prefer to use recycled cotton, especially since it is cheaper, but I don't want to sacrifice performance either.

Thanks!

08-23-13, 04:17 PM	#1
jeff88 Lots of questions Join Date: Aug 2013 Location: San Jose, CA Posts: 73 Thanks: 27 Thanked 2 Times in 2 Posts	Starting My Hot Water Conservation Project I picked up a water heater blanket at my local Home Depot today, but before I actually install it, I wanted to double check some things. It has an R-Value of 10. From what I have read, generally speaking 10/11+ is the best. (OK good, I'm off to a good start). I read that newer models have built-in insulation and so the blanket won't help much, so I should consult my owner's manual or the labels on the tank. I couldn't find it on the tank, but low and behold, the landlord was smart enough to leave the OM in the closet right next to the tank! Yay! The OM specifically says the blanket is "not necessary". It doesn't say I can't install one, but it also says problems are not protected if the blanket causes it. It doesn't specifically say what the R-Value is of the tank. So how do I determine what is "necessary"? I touched the tank and it was neither cold, nor hot, so without an infrared gun, I can't be sure how much heat loss there is (and I really don't want to buy one!). I bought a multimeter yesterday and it just happens to have a temperature probe on it. Maybe I can tape it up to the side of the tank and see what it says. At the same time, that reminded me of a temperature probe we have for another project. Maybe I will do one on two sides. Take a shower and see what happens when the heat starts to really kick in. One caveat, though, is that one wall of the closet is an outdoor wall, so during the winter it might get colder. A caveat to the caveat, however, is that it is west facing, so it will stay warmer than if the outside wall was facing another direction. My next question is a matter of preferences. Here is what I bought: Frost King Fiberglass R-10 Here is what I found afterwards: Duck Recycled Cotton R-6.7 My question is this: which is better? One is higher value, but is fiberglass (boo!) and the other one is lower value, but is recycled cotton (yay!). Does it really matter which one, or is the 3.3 difference large enough to make a difference? I would prefer to use recycled cotton, especially since it is cheaper, but I don't want to sacrifice performance either. Thanks!