| Click to Post a New Message!
Page [ 1 ] | | |
|
|
|
holding tanks
I've got an idea and want to see how it sounds. First, I seem to have a serious case of distraction this morning. I did proof read my other posts and still butchered a bunch of grammar. Sorry. My spell checker just informed me that I had misspelled ‘grammar’ as well. Tough morning!
The plumbing question is whether anybody has heard of a holding tank installed in the feed line to a hot water heater. The idea is to save electricity (in my case) by allowing well water to warm up in the house before if goes to the water heater. Some friends thought their oil water heater was coming on about every time hot water was used, and a holding tank was a plumber's solution. They say it noticeably cut their oil bills.
However, I'm not sure how efficient heat transfer from a conventional tank directly to air would be. I have looked around the net and found various specific heat exchangers designed for flowing water, which are also very expensive. I've been wondering if a set of 1" thin walled copper pipes with air space around them and standing vertically might work better. I figured that 6' of 1" pipe holds about a gallon. However, I'm not sure if a base and top for such a thing is available, and I'm not sure how to go about constructing one. It would end up weighing quite a bit, and depending on solder joints doesn’t seem a good idea.
|
|
 Add Photo
Bookmarks: |
|
| |
|
holding tanks
Tom, I am reminded of the free lunch deal. If you bring a tank of cold water into your home the BTU's to warm it has to come from somewhere. Do your have a solar heated room? I have worked with heat exchangers in the past. I hear that your water heater is electric. How do you heat your house?
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
I have seen all sorts of devices. One guy had a stacked version of the 55 gallon drum stove kit in his basement. Nothing combustable around them, but I wouldn't have wanted the thing in my house. He did what I have seen others do in the winter and that is to run Cu coils around the stove to heat water. Solar works well if you receive enough sun, we don't up here. Despite that, I have seen a number of water heaters on the roof or stand alone built from black PE or PVC, primarily to heat in-ground pools. In my area, we are offered time-of-use electric meters that have an off-peak rate of around 5 cents a kwh. I bought an 80 gallon energy saver electric hot water heater and timed it to run strictly during the off-peak hours. No fire to tend or cloudy days to contend with. Heats well too!
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
I have no solar, active heat exchange or wood furnaces in use. I've looked a bit and thought about a combination of solar and heat recovery from waste water. The equipment to do it seems pretty expensive and I wonder how long it would take to get the investment back. Of course our electrical rates are exploding, so maybe the answer is 'pretty quick.'
What's in my mind is a simple passive system. Get enough water in the basement and it would stay around long enough to warm up before triggering the electric heater. True enough that the basement would be cooler, but I'd just as soon it was for most of the year anyway. It also probably continues to get some ground heat throughout the winter. The house is heated by oil. At the moment it is cheaper than electricity by quite a bit, so I wouldn't mind if the furnace came on more often if it was keeping the electric water heater off.
However, maybe this 'do it yourself energy efficiency' isn't all that practical. Maybe Cutter's comment about a new water heater is the way to go. At the moment, I have a 'nothing special' heater wrapped with 6" fiberglass bats and covered with vapour barrier. It should at least store heat fairly efficiently. I guess I could put a loop in the output pipe. The idea is that hot water rises, so it comes up the output pipe and continues along horizontal runs until it cools. A loop in the vertical output pipe forces water flow back down and contains circulation of the hot water. I did that in another house, but it’s difficult to tell how much difference it made.
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
Tom;
The water from the well should be at ground temperature, therefore no heat savings from the basement.
I have a ground based heat pump which is hooked to an unheated 50 gal second tank. The heat pump heats the water to 120 when it is running. I like this system.
I built a heat exchanger quite cheaply using the stainless steel flexible connectors and PVC pipe. I can heat the pool using the outside wood burning stove and the exchanger.
Your problem is the heat source.
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
Tom, just off the top of my head I would have to say that it would probably cost you more to put together some system to pre-warm the water than you would save on the water heater's reduced consumption, or at least the payback would probably take more than the life expectancy of the system. Best of luck.
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
Tom I wondered if you had an oil fired boiler and baseboard heat. If you do there is a real nifty heat exchanger on the market that fits into the water tank and provides a nearly inexhaustible hot water supply. Several of my friends in Alaska had these units installed and swore by them (rather than at them) for convenience and costs saving.
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
In the geothermal system the cost of heating and cooling a 4000 sq ft house and providing hot water is approximately 50$ per month. With a conventional system the cost for hot water is 50$ and at least another 100$ per month to heat and cool. It cost me approximately 3.5 K extra not counting my time, therefore the payback is 3 years.
The crux is I am down to needed less than 700 watt hours. At current prices it would cost me about 10K for solar panels to disconnect from the grid. Now if the cost of the panels can just decrease to make it pay back in 3-5 years!!!
Link:
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
Thanks for the comments. There's a couple people around here who have wood furnace boilers that heat both the house and provide hot water. That's probably similar to the Alaska rigs. I've heard some pretty good things about them. I've also heard that wood furnaces are real wood burners compared to modern wood stoves. Unfortunately, there's nothing to work with, because we've got a typical oil burner forced air system.
Yep, the connection between basement and ground water temperatures is one I wouldn't have thought of. Perhaps I should have since I had an experience at my father's place in Lake Havasu City, AZ. The city water gets so hot just flowing through the system during the summer that many people turn off their water heaters and keep a jug of drinking water in the fridge. Nobody told me, and I took a somewhat extended shower, and spent most of the time trying to adjust the water.
A lot to be said for the idea of ground heat. I do think our basement gains heat from the outside during the summer and the furnace during the winter. At least we lightly insulated the pressure tank and some of the inside pipes to reduce condensation during the summer. Sort of ironic now because the condensation cure adds to the costs of hot water.
Like Murf says, if I cost anything that will make a significant difference out, I may find very long payback times. But then, it's a little hard to forecast future electric and oil rates. Don't know, but the deep well water is really quite cold here, and our friends thought a holding tank made a difference for them. However, their problem may be more related to the particular oil water heater. The problem was that it came on frequently after using only small amounts of water. Maybe the thermostat is located close to the water intake. I don't know how much heat goes up the chimney after each burn on a water heater.
|
|
Add Photo
Bookmarks: |
|
| |
|
holding tanks
Tom, a couple of quick(?) items that occurred to me afterwards, of course, sorry it didn't come to mind when replying originally. First if you have forced air type heating, hot water supplement is easy, they have coils that you install in your furnace's plenum sort of like a central air conditioner runs. Further to that idea, check out the link below, these stoves perform exactly as advertised, I have had several for years now, they were invented and built by a local here until recently when he retired & sold the business, they are not expensive, especially compared to those outdoor furnaces. Finally, there is a fellow in Manitoba who sells a 'how to' kit (that works, I tried it) to convert ANY oil burner to run used moter oil, etc. If I can find his name, etc., I will pass it on to you. Best of luck.
Link:
|
|
Add Photo
Bookmarks: |
|
| |
|
Page [ 1 ] | | |
Thread 37574 Filter by Poster:
1 | 1 | 2 | 1 | 2 | 3 | 5 |
|
()
Picture of the Day
brewdog
Unanswered Questions
Active Subjects
Hot Topics
Featured Suppliers
|
Gas Generator Weather Protecti
04-18-2002, 05:27 
Digg It 
Del.icio.us 
