Strider,

You might want to consider insulating the bottom of the water heater.

To my knowledge, the water heaters have some kind of insulation on the top and sides but nothing on the bottom.

Hot air rises but radiation goes in all directions.

If you could slip 1/2" of blueboard EPS (or maybe some of that aluminum bubble wrap) under the heater it might be your cheapest, easiest, most effective insulation, especially since your basement temps are as low as 16 degrees and your water temp is as high as 110, that's a pretty big delta-T.

I just found this:

Just a thought...

-AC_Hacker

I'll slip a chunk if 2" under the new heater before it's filled for the first time. It makes sense that they lose a bunch of heat down into the cold concrete right below it.

Graphs and temps for the last 2 days. The room with the hotwater heater is similar in temp to the blue temp line marked office.

Jan 15th
http://lh3.ggpht.com/_w1_9lMbNbxo/TT...s800/jan15.png

Jan 16th
http://lh4.ggpht.com/_w1_9lMbNbxo/TT...s800/jan16.png

So far this morning is hard to tell if it's a valid difference or not, the house was a bit hotter then the previous nights by about a degree. the hotwater heater kicked on at 1:07, 4:21 and 7:49 before regular water usage started at 10:22. So that is a little over 3 hours between reheats.

With a small amount of insulation, the difference won't be grand, but if the heater cycles on once every 3:00h-3:10h instead of every 2:50h-3:00h, then you should be saving something like 8% while in standby. Not bad:thumbup:

Jan 17th
http://lh4.ggpht.com/_w1_9lMbNbxo/TT...0/jan%2017.png

THe little spike near 10 at night is due to 1 of the current sensors getting unplugged so only half of the watts are recorded. I seriously need to move off of the breadboard soon. The same for the spike down on the recroom temperature.

Yesterday was easily our lowest hotwater usage with no baths or showers taken at home. Dishwasher didn't run and the one peak was a sanitize diaper load in the washing machine. It's looking like the stand by peaks are more spread out but it's still hard to tell. Maybe 20 minutes longer 2:50 to 3:10 or something.

Interesting saw-toothed wave of temperature versus time. I bet if you could record temperature with higher resolution, you'd see a different shape. How often does it show that your HVAC cycles on and off?

You can also see that the sun is shining on the thermocouple in the rec. room and the thermostat that controls the office, but not on the thermocouple in the office. It's another illustration that multi-zone HVAC = greater comfort.

Thats temperature taken every 2 seconds averaged and recorded every minute.

The hump in the orange line is from the woodstove getting refilled and opened up. the abrupt start and end to the climb is from it's fan turning on and off due to it's thermocouple. The sensor in that room is about 12 feet in front of the woodstove so it's really sensitive to the stove and it's fan.

The saw shaped recordings are from the fan in the forced air system kicking on every 15 minutes or so for 5 minutes o it's circulate program. I do this to move the heat from the woodstove around the house. I've actually found that just turning the fan on for 2 hours and then going to circulate does a great job of cooling the recroom with the stove and heating the rest of the house. I intend to eventually connect the downstairs cold air return to the recroom to make it even more efficient.

The rec room gets sun but the office does not on the jan 16th graph around 1 in the afternoon you see this small hump.

Higher temperature resolution may be required for a more accurate idea of the waveform.

Your ripples are 2°C (3.6°F) tall. That's probably acceptable, and about the same as I have in my house. But I'd like my next house to be unconventionally comfortable, not just efficient. Hence, if this were my ideal house, I'd want the fan to run at a low RPM and a 100% duty cycle, instead of the full RPM / 25% duty cycle that your current hardware is capable of.

Oh the sensor is set to 12 bit resolution and readings are within about .3 of a degree. I'd have to do some software changes to see every 2 second readings or at least something other then the minute by minute average. The reason for the big swing is because the sensor is sitting on my work desk basically right in the airflow of the furnace vent in that room.

yesterdays graph now with a front yard and a backyard sensor.
http://lh4.ggpht.com/_w1_9lMbNbxo/TT...s800/jan18.png

the funny yellow and red spike at 4 in the afternoon happened when I cut the wire for the front yard sensor to extend it.

I find it funny that the two sensors report a difference at night in the yard. The front is south facing and does get hot during the day so it could be residual or it could be something to do with the 40 feet of wire making the reading come in a little different. either way It's accurate enough to make me happy.

Looking at the mornings standby periods it does appear that the little bit of insulation has added about 20 minutes to the period. So it is a measurable savings.

Dragging this one up from the dead.

Since the last post I replaced and relocated the hotwater heater.
Basically it's a 60 gallon bottom entry 6year tank which I wrapped with the foil bubble wrap, then added an insulating blanket to. Under the drain pan I put 2" of polyiso. I also added a loop to the hot coming out to act as a heat trap.
details are here
http://ecorenovator.org/forum/applia...r-install.html

I did this back in july and noticed my bills were lower then last year but couldn't tell exactly how much the new tank made a difference as my collecting device was taken apart and hadn't been used in quite awhile

Yesterday I installed a TED-5000.
Here is last nights power usage
https://lh6.googleusercontent.com/-s...ght+heater.png
basement temps were comparable to those in the previous graphs.

As you can see the old heater would kick on and to maintain temps for 4 minutes roughly every 3 hours
The new tank came on for 5 minutes at 3:19 and again at 7:53 so 4 and a half hours apart.

That's a big improvement. I'm assuming the biggest improvement comes from the heat traps. Insulation is good but I don't have enough to account for that big of a difference in my mind.