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Gas hot water heater with high R-value insulation

Posted by peggydobbs (My Page) on
Mon, Dec 11, 06 at 18:57

I have located 2 gas hot water heaters (a Kenmore Power Miser 12 & a Bradford White M4) with 2" insulation. The Kenmore specs say that the 2" insulation has an R value of 16 (R16).

Does anyone know of a manufacturer that offers even more insulation (i.e. more than 2 inches or an R value higher than 16)?

Many thanks. And please, no responses saying I should go "tankless"--it's not cost effective to retrofit--I've looked into it, believe me.

Follow-Up Postings:

RE: Gas hot water heater with high R-value insulation

You're probably having a hard time finding one because more insulation means larger, more expensive outer shells and more problems to fit these in tight spaces. The simplest and cheapest solution if you want more insulation is to just add a water heater insulation blanket to the exterior. However, if you already had R-16, doubling the insulation would not necessarily save a huge amount of energy. R-16 probably saves 95% of the heat loss compared to an uninsulated tank, So twice as much insulation might save you another 2%. Is that enough to make a difference to you? Also, where is this water heater to be located...inside the house, or unheated garage?

RE: Gas hot water heater with high R-value insulation

The hot water tank is in an unheated basement. I don't think it ever gets below about 50 degrees F, however.

RE: Gas hot water heater with high R-value insulation

Hi Peggy.

One thing I considered doing (but haven't yet)is boxing in my gas water heater, so it would be in its own little room. That would save quite a bit of insulation, and enable me to run the combustion air to an enclosed space so that the heater wasn't pulling cold air across the sills and such.

Just FWIW.


RE: Gas hot water heater with high R-value insulation

Dear Mark,

I believe that direct venting pulls air in from the outside directly into the heater, thus (as you say) avoiding pulling air from the room, which is replaced by (cold) air from the outside.

Unfortunately, I prefer not to direct vent for the same reason that I don't want to go "tankless", namely, I don't want to run a pipe or pipes through the side of my house.

You are right, however, that doing so would save energy.

Thanks, Peggy

RE: Gas hot water heater with high R-value insulation

I am looking to replace a old scout hot water heater that was a mobile home type with something of super high efficiency as possible. I am stuck with electric but is there one that is super insulated in the electric type at 30 gallons. Maybe even 25 gallon? I am single and dont use much hot water. I may install a demand timer since after 7 PM my hot water needs are rare, and have turn on around 7 am. I plan to also insulate the Box it will sit in. I am trying to get my electric bill as low os possible and the hot water heater is about 80% of my electric use right now. With a gay water heater I rarely went over $20 a month and most times was right around $16.00 a month, thsi hot water heater is using almost $30 maybe more a month by itself. I wash clothes in cold water do all the right things.

my email is for any ideas

RE: Gas hot water heater with high R-value insulation

You may want to look at heat pump water heaters.. that's the highest efficiency possible. Very expensive, though.

RE: Gas hot water heater with high R-value insulation

Just to clear up an issue:

Virtually all electric resistance water heaters are near 100% efficient. That is to say that they convert almost all of the energy input into hot water.

Separate issue from efficiency:
They do have standby heat loss-- although that is not as much as a similarly insulated gas heater.

To answer both the OP question and James' question: A 2" foam insulation, which has an R-16, is common. Less expensive models will have an R-8.

It is usually less expensive to buy a heater with an R-16 and then add a blanket (R-10) for $20 than to spend lots of money on a "super insulated heater". If you have achieved an R-26 on your heater, I would look for other ways to conserve energy. CF light bulbs, for example, would have a much greater payback.

RE: Gas hot water heater with high R-value insulation

My brother bought a new water heater about 3 years ago now but it was electric, but has 3" foam insulation in it-or so it said on the book. You might find a gas one like it. He got it at Lowes and it is a Maytag. Don't think they have Maytag now but not sure. You might check their website and see what they have and where dealers would be close to you.

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