Water Heater 'Blankets' - Anyone know anything about these?

C

Cut-Throat

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I have heard it's a good thing to put an insulating blanket on your hot water heater. Mine is about 9 years old - came with the house. The outside of it always feel cool to the touch, but I suppose the more insulation the better.

Are there different types? How much do they save on average? Best Brand or Type to get? Home Depot or Lowes or ?

Educate me! :confused:
 
I put one on my water heater (foam sheet) and insulated the couple of feet of bare pipe between the water heater and the wall where it enters the house. I couldn't see a discernable difference in expense, but after draining the tank by filling up my whirlpool bathtub during the winter I seem to get hot water available more quickly. My wife also thinks we get warm water out of the faucet at the other end of the house a little more quickly.

Remember, that I live in Arizona and much of the year my cold water is hot enough that I don't need to turn the hot faucet on. I only put the thing on my water heater because a friend who was moving out of the country gave it to me before he left. I figured it couldn't hurt. :-\
 
CT,

The water heater blankets are not as popular as they once were. Newer water heaters are much better insulated than the older ones.

- The two types I've seen are 1) Fiberglass insulation with a flexible plastic facing and 2) a matted fiber substance with a reflective alluminum foil face. I think both Lowes and HD sel Type 1 (Maybe the "Frost-King" brand?) and I think I saw the Type 2 at Lowes. Oh, I've also seenthe reflective bubble insulation marketed for this purpose. I think the fiberglass-with-plastic version is the most effectve, but the most inconvenient to install (fiberglass itchiness if not careful, etc). I've done it twice, it is a simple job if you can get access to al sides of the WH, and took about 1 hour total.

Savings: YMMV. Depends a lot on whether your present tank is well insulated, if you have a gas or electric water heater, and if the WH s located inside your conditioned space. If the WH is in your conditioned space, then youmifght not save very much at all in your MN climate, since 9 months of the year you're hapy to have the extra heat in your house.

Sorry for the lack of specifics.

Oh, two other related projects:
-- Insulate the hot water pipe leading out of the WH as far as you can reach/see it. This saves on energy leakage all the time ad slightly reduces the wait for hot water if you've recently used it.
-- hen it is time to replace the WH, be sure to get the "flapper fittings" nipples that reduce water flow when you don't have the water turned on.
 
I looked into them a couple of years ago - the guys at Home Depot and Lowe's all seemed more interested in selling me one rather than giving me the whys and why nots. What I found on my own is that many newer model water heaters will tell you not to use a blanket, especially gas fired models. On the gas fired units you have to be very careful about placing the blanket (not on top or near the flame source) or you can heat the whole house with the resulting fire. If you can find the owner's manual you might want to check there first.

One common sense idea I found was to put your hand on the heater exterior. The warmer it is to the touch to more energy you're losing.

Other good ideas are to turn down the temperature and insulate the pipes that carry hot water from the tank to the faucets.

I opted to not add a blanket (gas fired heater, manual said don't, and neither unit felt all that warm to the touch), but I did drop the temp on one unit and insulated all the pipes.
 
I have one and it works great. I bought the most expensive one they offered at Home Depot - I think it was around $50.00. It has paid for itself over the last year or so. When we put it on the gas bill dropped about $5 a month. I live in So Cal so the climate is warm, I'd imagine you would save more in colder areas. :)
 
I would not externally insulate any type of water heater with a flammable insulation, or an insulation with a flammable face.

Leonidas wisely points out the warning about gas water heaters. The issue about the top of gas water heaters isn't only about obstructing the flue, but also about defeating the purpose of the draft diverter on a atmospheric-burner type of water heater. An atmospheric burner uses the concept of heated gases rising, as opposed to an induced-draft powered burner.

Water heaters manufactured in the last 10 years or so have a lot of insulation, unless you are buying the el cheapo units. Putting insulation in series with insulation reaches the point of diminishing returns very quickly.

If your water heater is in a closet, where it helps to self-heat its environment, then the small air space and walls become part of the effective R-value.

But if your water heater is set at 145 F, and is in a basement at 45 F, then the temperature differential is high, and additional insulation, if done safely and at reasonable expense, will probably help.
But if your water heater is set to 120 F, and is in a 70 F environment, then I think the placebo effect comes into play if you externally insulated it.
 
Dh and I just had this discussion and he said no to the blanket. As said earlier the waterheaters are insulated quite well these days, older models (very old) could use it but it's not something to waste money on now. A few years ago he insulated all the piping and that seems to help a great deal.

Dh worked for a prophane gas company and they would push the blankets big time but everyone there knew they didn't need them, it was just a money maker.
 
Two tangential things to add:

1. Consider an on-demand water heater. Ours, installed two years ago, has already paid for itself. The only downside is that it takes longer before totally hot water gets to the faucet (with a tank, hot water diffuses into the pipes).

2. Don't forget to drain your tank water heater once a year. I'll bet fewer than 5% of people do this, but it will extend the life of the tank.
 
Hi Everyone--


I have a gas fired hot water heater that I used an insulating blanket on several years ago. The house is exactly 20 years old, and it is the original tank that sits in the garage. I will tell everyone that it does make a difference in costs to operate as the themostat can be reduced. It also stops much of the natural dissapation of heat to a cooler space. But it is VITALLY IMPORTANT to use caution when placing the blanket near the burner or the flu. Keeping the insulation away from the burner is necessary if there happens to be a flame rollout whee the flame comes out of the burner compartment because of a malfunction. I would suggest not even attempting to cover the top of the tank where the flu protrudes dure to the high heat generated.

I think my blanket cost about $17.00 when I installed it 10 years ago. And I will tell you that the tape they provided was useless. I used gray duct tape and it is still holding.

When draining the tank, do it in the early morning when the sediment has settled to the bottom. Drain out 3 or 4 gallon buckets. The drain may leak after so have a threaded end cap that you can screw on to stop the leak.

Professor
 
There are sites that tell how to do it. When i did it I'd drain the tank completely, and even turn the inlet suppy on to stir up the sediment so that you can get it all out.
 
TromboneAl said:
There are sites that tell how to do it. When i did it I'd drain the tank completely, and even turn the inlet suppy on to stir up the sediment so that you can get it all out.

Are we still talking about water heaters?
 
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