Super insulate your hot water tank

Daox · 12-13-10, 11:28 AM

A great article on how to super insulate your hot water tank. He also explains how to find the ROI for the insulation. Very well put together IMO.

IWillTry.org Super insulate your hot water tank

RobertSmalls · 12-13-10, 06:20 PM

Ah, yes, from Iwilltry, the author of a coastdown testing instructable.

You know you're an ecorenovator if anything worth insulating is worth superinsulating.

Daox · 12-13-10, 08:43 PM

Quote:

Originally Posted by RobertSmalls

You know you're an ecorenovator if anything worth insulating is worth superinsulating.

Woohoo, you betcha!

Piwoslaw · 12-14-10, 01:41 AM

Quote:

Originally Posted by RobertSmalls

You know you're an ecorenovator if anything worth insulating is worth superinsulating.

That's a good one

You should put it in you signature so doesn't get forgotten.

RobertSmalls · 12-18-10, 02:38 PM

It's all you, Piwoslaw.

PastTense · 12-19-10, 12:37 PM

From the article:
"Where I live electricity costs about $0.07 per kWh so a typical electric water heater with no additional insulation might cost about $150 per year to operate. Depending on use, perhaps $50 of this is actually used to raise the temperature of the incoming cold water. The remaining $100 is wasted in the form of heat dissipation to the surroundings. "

Do you agree with these kinds of numbers as to how much of the energy is dissapated as waste heat? I was under the impression that the the substantial majority of the heat is used to heat the water. Anyone have better numbers?

Also note part of the waste heat will still be wasted--top and bottom of water heater.

Daox · 12-19-10, 01:17 PM

The writer of the article did insulate the top. I don't think he mentioned insulating the bottom at all, but its a good idea.

RobertSmalls · 12-19-10, 04:26 PM

Quote:

Originally Posted by PastTense

Do you agree with these kinds of numbers as to how much of the energy is dissapated as waste heat? I was under the impression that the the substantial majority of the heat is used to heat the water. Anyone have better numbers?

I guess that depends on the amount of hot water you use, eh? But it seems plausible to me.

To avoid having to look up the UA of your HWH, try a simple test:

Record the temperature of your hot water. Shut off the heater, wait 24 hours, and take the temperature again. How much heat did you lose? This is equivalent to wasting a certain amount of hot water a day - how much?

Daox · 12-19-10, 09:12 PM

That is a great idea. How would you recommend measuring the before and after water temperature?

RobertSmalls · 12-19-10, 09:59 PM

I'd open the drain penis until it flows hot, fill a styrofoam cup with water (or nested plastic cups for the eco-friendly), and measure the temperature of the water in the cup.

The easy way is just to measure the temperature of the water in your kitchen, but that introduces all kinds of unknowns, like how much heat is lost in the pipes.

Edit: the forum censored out "draincock". Now it gets what it deserves.

12-13-10, 11:28 AM	#1
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Super insulate your hot water tank A great article on how to super insulate your hot water tank. He also explains how to find the ROI for the insulation. Very well put together IMO. IWillTry.org Super insulate your hot water tank __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

12-19-10, 01:17 PM	#7
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	The writer of the article did insulate the top. I don't think he mentioned insulating the bottom at all, but its a good idea. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

12-19-10, 09:12 PM	#9
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	That is a great idea. How would you recommend measuring the before and after water temperature? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

12-19-10, 09:59 PM	#10
RobertSmalls Journeyman EcoRenovator Join Date: May 2009 Location: Buffalo, NY Posts: 344 Thanks: 3 Thanked 17 Times in 15 Posts	I'd open the drain penis until it flows hot, fill a styrofoam cup with water (or nested plastic cups for the eco-friendly), and measure the temperature of the water in the cup. The easy way is just to measure the temperature of the water in your kitchen, but that introduces all kinds of unknowns, like how much heat is lost in the pipes. Edit: the forum censored out "draincock". Now it gets what it deserves. Last edited by RobertSmalls; 12-19-10 at 09:59 PM.. Reason: It censored out draincock.

12-13-10, 06:20 PM	#2
RobertSmalls Journeyman EcoRenovator Join Date: May 2009 Location: Buffalo, NY Posts: 344 Thanks: 3 Thanked 17 Times in 15 Posts	Ah, yes, from Iwilltry, the author of a coastdown testing instructable. You know you're an ecorenovator if anything worth insulating is worth superinsulating.

12-18-10, 02:38 PM	#5
RobertSmalls Journeyman EcoRenovator Join Date: May 2009 Location: Buffalo, NY Posts: 344 Thanks: 3 Thanked 17 Times in 15 Posts	It's all you, Piwoslaw.

12-19-10, 12:37 PM	#6
PastTense Lurking Renovator Join Date: Dec 2010 Location: Iowa Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	From the article: "Where I live electricity costs about $0.07 per kWh so a typical electric water heater with no additional insulation might cost about $150 per year to operate. Depending on use, perhaps $50 of this is actually used to raise the temperature of the incoming cold water. The remaining $100 is wasted in the form of heat dissipation to the surroundings. " Do you agree with these kinds of numbers as to how much of the energy is dissapated as waste heat? I was under the impression that the the substantial majority of the heat is used to heat the water. Anyone have better numbers? Also note part of the waste heat will still be wasted--top and bottom of water heater.