If I recall properly, your heater is in an unheated basement. As the cold season progresses, it will probably cycle more often.

As I calculate it, your DWH is cycling 5.3 times per day, and since it holds 501 pounds of water, and it is raising that water 4 degrees F every cycle, you are losing 2004 BTU per cycle or 10,687 BTU per day into your unheated basement.

If you re-located the DWH to being inside the house's heated envelope, the delta T would be lower, so cycles would be much reduced, and what heat you did lose would be heating the living space.


Just a thought...

-AC

Nope my basement is heated. temperatures range from 17 - 21 down here depending on if the woodstove is lit. lost heat from the heater just goes towards heating the house. my regular heating is woodstove and the Heatpump so the heat from the heater is just less efficient then my regular heat sources.


Next peak just happened. 5 hours 15 minutes between this time everyone is home now so I doubt we'll be getting to almost 7:00 without using hot water.

I like the timer idea, I will have to see if my grey metal boxed timer will work with 220 volt.

What i want is a tankless water heater, when its time to replace my tank I'm going tankless. One upstairs, one downstairs. My kitchen and washroom are next to each other so one between is feasible.

I was playing with my IR thermometer this morning, and since the hot water hadn't been used in awhile I decided to check the line temps in my heat trap. Checking the TED the heater hasn't run in 4 hours and the last measurable hotwater usage was 14 hours ago so it's likely that line temps have returned to there standard no hotwater usage state.

Here you can see the trap on the wall, it's just a down over then up.
https://lh4.googleusercontent.com/-T...3/IMG_6038.JPG

The top of the trap right before the down is currently reading 30.3 C behind the insulation. The bottom of the trap is reading 22.6 C

The foam insulation read's 23.4C at the top and 22.1C at the bottom.

The tank insulation reads 21.6 at the top of the tank and 20.9 C at the bottom of the tank. the wall behind the tank reads 21.5C at the top of tank height and 19.8 at the floor height.

So the loop is really helping reduce the amount of pipe that is heating up due to rising hotwater from the tank. The insulation on the pipes is also making a big difference compared to bare copper that I originally had. All of the hot parts are still reading higher then ambient temperature but only by a little bit. If I find some insulation that fits I may wrap the 15" or so of pipe going into the top of the tank a bit more but beyond that I'm pretty happy with this.
The tank could also use more insulation. The TED says it kicked on for 4 minutes at 10:14, 12:36, 3:55, and 7:29 The last hotwater usage was at roughly 8:00. so that's 16 minutes of standby overnight or 1.2 kwh costing me 8 or 12.5 cents depending on which tier my electric bill is in. assuming things were to stay like it was last night and we go worst case highest cost tier that's $45/year or 438 kwh in standby losses. That's a crap load but nowhere near enough to justify the cost an on demand would have cost me. That amount could easily justify a 220V timer however. I'll see what I can find

I'm currently thinking in the long run the tank and the solar hotwater storage tank will have a closet built around them and that will be insulated as well. I'm not convinced that wrapping another insulation blanket around the tank will make much of a difference but if I see something that will work I'll buy it and give it a try. I wish they made 4" foil backed fiberglass or rock wool and it was available around here.

Is your pipe still copper? If so, you might want to switch it to PVC as it has 100s of times the thermal resistance.

roughly the first 10 or so feet is now pex and the first 20 feet is insulated.

I posted this a while back. I dunno if you ever saw it. It is basically as you mentioned doing, building a frame around the water heater and insulating it. Doesn't get much better than this!

http://ecorenovator.org/forum/conser...ater-tank.html

http://www.iwilltry.org/b/wp-content...ank-during.jpg

lol yeah that would fix the standby losses. how hard is it to get into and drain the tank?

Easy if you plumb a ball valve out through all the insulation! :)

I'm just reading that post on the super insulated tank.

I'm not sure how useful his numbers actually are although the insulation idea is good. First issue is he has a gas heater converted to electric. So he's got a big vent through the middle of the tank to lose heat from. he's also got a 520 watt element to do the heating. meaning he was running the tank for 3 to 6 hours each night to heat the water. doing the math that means before insulating the tank he used 3.12 kwh and after he used 1.56. Plus he states that he's using a timer which has reduced his runtimes already.

So super insulated and using a timer he's using more power then I am with some of the shelf blankets. Either he has his temperatures way higher then I do ( Straight hot is too hot for me to shower in but my wife can stand it) or something else is costing him a ton of energy.
I suppose the other possibility is he doesn't run the tank at all during the day so his nighttime readings are also recharging the used heat not just the standby. In that case he's better then my tank.