Sounds like fun to me. I asked the wife, she said it was fine as long as she was gone! :) Oddly enough, she'll be gone for a whole day this weekend, so that works for me.

I've actually found that on sunny days the house heats up unless the temperature is below 0C outside. Pretty much every sunny day is furnace free day around here.

I was looking at them online.. The HiFi guys use some fancy looking stuff.
Big bucks too. Most of the less costly units will not do 3kw..

The NStar tech found out that my section of the Grid was putting out
127/254 in two neighboring towns. He tweaked the local transformer
and got me down to 124/248! I'm inside the "187 to 253" Voltage Range!

Maybe some day we can get the regular 230-240 service!


The Sanyo seems to like 248 better.. It only went nuts once today.
I tried to turn up the temp a little too fast..
I guess we will see tonight. I'm hoping not to be awakened by Beep-Beep again tonight..
I've been installing my new panels all afternoon and I'm beat..

PS:
I tried leaving the Sanyo set to 21C (69.8F) overnight last night, but failed..
Now that the line voltage is lower, I'm going to try it again.

So, starting at midnight tonight, I'm going to leave it at 21C and see how much more power is used.
Since the average lately has been 10-11 kWh, then 12 to 15 on average might be acceptable.
Might as well get it while it's cheap.. Besides, the cold isn't helping the arthritis in these old bones..

Note:
It's 8AM Wednesday and the Sanyo seems to have used 2.67 kWh (56 cents) since midnight.
The outside temp was in the mid 40s F.

http://ecorenovator.org/forum/attach...1&d=1380209560

20c=68f
15c=59f
10c=50f

Away from home: Temperature above freezing, I'll set the temperature to 45 degrees. Below freezing, I'll set it to 50 degrees. After the house was at 45 degrees for a long time I measured water temperature out of the faucets and got 39 degrees. 7 degrees to freezing is a little too close for comfort when it comes to water in pipes for me.

When I'm home and active: Usually at 55 degrees unless I'm going to be doing a bunch of moving around. I'm usually not bothered by this temperature at all unless I spend more than 30 mins in the kitchen which is about long enough to cook up almost anything. This is with jeans, tshirt type wear. Socks required on the bathroom tile and kitchen hardwood.

If I'm home and sleeping: I'll set(or leave) the temperature at 50 degrees and use my mattress pad heater to make up the temperature. With the 100 or so watts, if I leave it on high I will sometimes wake up to turn it down.

If I'm home and in bed: I spend plenty of time on the computer, tv, eating, reading various books or magazines and if I can do it from bed, I will when the weather is cold. 50 degrees for this too.

When I have people over: I turn it up to 65 degrees, nobody has ever complained. Most people enter my house and say it feels a bit warm as they take off their coat. Due to cold and snow, I usually don't invite people here that often during the winter.

The only thing that kills this is if the humidity drops too low in the house because then suddenly even 60 degrees feels cold. I balance the humidity with how I take showers and leave the door open between the shower and the bedroom with the exhaust fan off. At 40% humidity 65 feels cold. At 55% humidity, I can handle 55 degrees. 60% and I can comfortably walk around for awhile in the house at 50 degrees. I must be careful though, right now it is 18 degrees out and 55% humidity is condensing the bottom of my windows so there are limits to how far I can go with humidity to try and maintain comfort. I'll add thick layer over my tshirt.

Heat loss is a weird thing. If I set my house from 50 degrees to 70 degrees and turn it down to 50, it will lose 4 degrees in the first 15 minutes(possibly the anticipator on the digital thermostat and thermal mass absorption though), then will drop slower and once it gets down to 60 or so it takes pretty much all day to get to 50 again. On recent 20 degree days, at 50 degrees the furnace cycles on once every 2 hours or so for 5 minutes or less. At 55 degrees, it's 5 minutes every hour or about an hour a day. At 60 degrees it runs for 1.5-2 hours a day. Haven't tested 70 degrees. If I did I'd have to wait hours for thermal mass temperatures to equalize to the higher temperature and then pay attention to it.

RobertSmalls, I'll join your 'furnace-free day'. I've already joined in November, more or less. I've run an entire day at about 20f outside starting by running the temp from 50f to 65f when I woke up(~11f degree rise per hour). Waiting for the cooldown and ended up going to sleep and wasn't sure when it actually kicked on for 50f again. The problem is, my house was designed at a bad angle where in the winter the sun comes down a little too south for my SW wall to get enough solar gain to be worth it but in the summer the sun is still up as it passes west and the house gets very hot. ...so my losses aren't helped much with gains from the sun, which really sucks. I've considered chopping the SE wall of the bedroom, using an appropriate awning for the summer with a window that will allow as much of the winter solar heat in as possible and filling in the NE facing wall that has a window that doesn't do much. ...oh wait, I'd be staring at a house and it would block a decent amount of the sun. S#$%

Remember that if you ever move. My last house was on a north facing hill. I needed larger to fit the ever growing family and insisted on effectively perfect solar exposure. It's made a huge difference. Everything else about the house could be wrong and I'd still be ok with it because the only thing I can't change is the position of the sun.

The energy usage doesn't seem too bad considering the lack of winter sun, that at least 9 of the windows in this house have a 5/8"(1.5cm)air gap all the way around that isn't sealed yet(active project at the moment), only about 8 inches or so of settled cellulose insulation in the attic and a few spots I've identified on the walls where entire sections between studs appear to have insulation problems as they read 10 degrees colder than the section right next to it. I have a feeling it might not be too bad once I get the attic up to R60, fix the air gaps and insulation voids. I'll probably raise the temp to 60 or 65 once that is done. If my furnace breaks in an expensive way such as the heat exchanger cracking or something, I'll have a 95+% efficient natural gas furnace to replace the 76% efficient non-condensing once I have now.

I am (still) doing my super major overhaul with solar electricity and heating, long term heat storage, insulation, drain water recovery and ... g.. knows what. For now most rooms is regulated by simple thermostats on each radiator, although a newly built room and a refurbished ones now have underfloor heating.

The new heating system (hot water buffer) regulates the outflow temperature in two independent heating circuits, so I use #2 of those for the underfloor heating, and #1 for the original radiators.

Temperature here is just around 70, but as each room has it's own mind, it varies a bit.

My project is so comprehensive that just speaking of temperature in itself is only part of it. I have almost 1000 USG of water heat storage, apart from the 300 USG main water buffer tank (hot water is piped, not conventional tank water, so it can be used for cooking, coffee and so on).

As all window glass has been changed to super efficient glass, it was interesting to see how well the underfloor heat would keep the new rooms warm. A few days ago it was almost -20F (actually, C and F meet at -18), and that morning I could feel the cold from the window.

osolemio,

It sounds like you may have one of the most comprehensive renovations going on at EcoRenovator. We would all like to know more details and to see photos of your progress.

I have at least one room in which I want to put underfloor heating, and I would like to know all the details you could possibly share about how you are doing yours, with diagranms & drawings & photos if possible.

Why two independant circuits? Is it because one was already in place and you didn't want to disturb it?

What kind of storage tank are you using for heat storage? That's a very large storage tank, but when I did the calcs for my place, I came up with the need for a similar sized tank.

When you say super efficient glass, do you mean truple pane? I know that in Europe there are much better windows avaulable than in the U.S., can you give us more detail?

Regards,

-AC_Hacker

Oh, it is quite comprehensive indeed. I have posted various things about it here already if you follow my posts. Let me try to answer your questions one by one, sorry don't know how to quote as nicely as you did :)

Underfloor heating is not that difficult. But if you keep a mix of radiators and underfloor heating, you should either have two heating loops, or you could have one loop where the water goes to the radiators first, then through the underfloor heating (possibly via a shunt).

There is not that much to it. You got to have the right tubing, and I have something called aluflex, as it is easier to work with. It is aluminum inside, covered in some coating. You can bend it and it stays in shape, but if you bend it too many times it breaks! Not a problem as long as you are gentle. You can also use tubing without aluminum, just make sure it suits the purpose. Insulate the base if needed, then put out a iron mesh used to fortify concrete with something to lift it up an inch or two. Then route the piping keeping a distance of about half a foot or so, depending on the distance from the tubing up to the top of the floor. If you want an even distribution, keep it closer. I am sure there are lots of good guides on this if you search online.

Regarding two circuits, I explained it above already. The Okofen allows quite good control over the heating, and the radiators require a much higher temperature to keep the house heated when it gets cold outside, while the underfloor requires a lower temperature. Also, the underfloor takes hours or even days to react, while the radiators are much quicker.

The water tanks I have is the 300 USG Okofen tank as main buffer (it includes the control), then I have three pallet tanks, each just over 300 USG as well. These are dug into a hole in the ground, insulated and then on top, there is the new room of the house (expansion). Piping from there goes to a system where I can mix solar heat, stored heat with the Okofen buffer, as well as route heat under the house, and even around the foundation of the house (!) which I am about to insulate, on the outside (long story).

The glass is way better than the old glass I had, but not the super best you can get. Only dual layer, with argon gas - the krypton gas is just too expensive and not that much better. I cannot go triple layer as I exchange glass in existing frames and they do not allow more than a certain thickness. We had a lot of snow recently, and those windows in the roof (45 degree angle) need to be cleared of snow! Before it would eventually melt, but not any more. Too good insulation in them. The windows are brand Velux, those at 45 degrees, I don't know what brand the glass is.

Serious Windows use multiple layers of plastic between two layers of glass to add to the R value of the window. They have the highest R-values I've ever seen in any window. Their highest R value rating is 11.1 for a non-opening window.

Serious Energy Efficient Building Materials

http://ecorenovator.org/forum/attach...1&d=1380209902