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DIY HVAC
An anonymous reader writes "I found this very interesting project called DIY Zoning. It allows one to add air flow balancing, temperature control, zoning, home automation, and more to an existing or new HVAC system. After getting a $200 electric bill, this sounds like a good solution for those who are getting screwed with outrageously high electric bills due to their HVAC unit especially since organizations like TVA have raised the electric rates."
Put the real thermostat somewhere hidden and place a dummy one in the hall for the wife and kids.
Putting a circuit in to turn off the AC when someone opens a window helps too.
Beep beep.
Would there be anything wrong with using your shower water as toilet water? I honestly can't see anything wrong with that and it'd certainly cut down on somebody's water bill from month to month.
A friend of mine is doing this himself using parts from a website (the name escapes me) and drivers that he is writing himself. I also ran into this a while back. It looks like a lot of work, but considering how much a system like this would cost, its probably a pretty fair bet for experienced hackers with some spare time.
Does anyone remember way back in the BBS days of the early 90s (when the net was new or undiscovered for so many) when HVAC meant "hacking, virii, anarchy, cracking"?
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What a weird yet fitting title to see on
This is going to be the vaguest answer you ever got:
I saw a program on PBS or The Discovery Channel or HGTV or God knows what channel...
about a hotel in Arizona or Malaysia or Australia or god knows which country
which has a water recycling system installed. They have low flow toilets, and a filtration system, and the water is in a clear acryllic case. All the water for the all the systems is mostly recycled.
What is the fate of a few third-world countries compared to the convenience of a heated driveway.
Throw that snow shovel away!
Or rain water. You could save rain water for several purposes, like toilet water and watering your lawn.
It's even mandatory these days to install a rain water reservoir for new houses (here at least).
On a similar note, we have no choice of who we buy our water from, and who we give our sewage to.
Need a Catering Connection
But my swamp cooler keeps the house cool and saves me a lot of money over my A/C cooled neighbors.
Evaporative coolers use electricity only to spin the fan vs. compressing freon or whatnot, which takes a lot more energy.
Treatment, not tyranny. End the drug war and free our American POWs.
See my user info for links.
Kudos is deserved for a +5 first post.
That's all fine and good. In fact, it's excellent.
But a good HVAC system will save you electricity AND fuel, being better able to meet the heating/cooling demands better. That translates to lower costs all around - AND more comfort!
A good HVAC system doesn't even need to be all that complicated, either. Chances are it's already possible to have your home re-evaluated and do a minor tweak to save a few bucks.
If you've got baseboard heat (hot water), and ever had or will soon have your boiler replaced, it's worth doing a detailed heat load calculation. Chances are the guy installing the new boiler will probably size it up to handle what the radiation is designed to put out - and typically it's quite a bit more than you actually need to keep the house comfy warm!
This results in the boiler cranking out more hot water than is actually required, and with a single-zone system you'll end up with some rooms too hot and others too cool. The boiler will also short-cycle more often, resulting in poor efficiency.
There's several solutions you could use. Putting the right sized boiler is obviously the best way to go if you don't want to redo the whole house, but if you've got plenty of radiation (and a newer, non-cast-iron boiler!), why not run your system at a lower water temperature? The boiler won't have to work as hard to get up to temperature, and it'll stay off longer (feeding off the latent heat to keep the water warm). A simple tweak of the boiler's temperature shutoff and a 3-way mixing valve is usually all it takes.
While you're at it, clean that fintube. Maybe throw some insulation on those pipes in the basement. Little things like that are easy to do and certaintly can't hurt.
=Smidge=
Indeed, one of the problems we have, conservationally speaking, is that we use our drinking water for everything. There is no water shortage, overall. We have just as much water after you flush your toilet as before. It's just that that water is no longer suitable for drinking.
Would you buy bottled water to pour into your toilet? Probably not, and yet that is essentially what you're doing right now.
I like to use a good, old fashioned cistern, a big bucket to collect rain water, for many uses that don't involve ingestion. Why buy "bottled water" to spray across your lawn/plants? Hell, your plants even like it if it's a bit, ummmm, shitty.
You can learn a lot about water managment by reading books on sailing. When blue water cruising, management of drinking water while still getting other things done requiring the use of water can mean the difference between life and death, not merely a larger water bill. Salt, rain, grey and fresh drinking water all have their various ideal uses.
KFG
And that's for a business? Now you understand what the whole ruckus was about in CA, back in 2001.
My home electric bill is roughly $200 (The water is also about $200). And that's LA DWP, which was a damn sight better than the poor fools who got 10x rate increases during the crunch.
The only reason we have the rights we have is that people just like us died to gain those rights. -- Cheerio Boy
The run-off from showers / sinks is called 'grey water' (as distinguished from toilets, 'black water'). Just Google for 'grey water recycling'.
The sensible heat load is the outside temperature seeping through the walls, but it is also the sum beating down on the roof and walls and pouring through windows. The latent heat load is largely the result of air infiltration with some contribution from showers and cooking: running a dryer contributes to latent heat because it pulls 150 CFM of inside air through the dryer vent that gets made up by air seeping in.
One of the points made was that in fall in Florida, the air conditioner runs less so the indoor humidity climbs to the sticky range. They are recommending a variable speed air handler so that a low flow setting, the air gets chilled more so more of the AC goes into humidity removal. Heat pipes have been recommended as well -- to pre-chill the air handler input and pre-warm the output to trade less cooling for more condensing.
Other approaches include not running your fan in continuous mode because that just evaporates the moisture film on the coils every time the AC cycles off to better draining cooling coil pans.
But a fundamental problem is that the latent heat load is pretty much constant across the day while the sensible load varies with the sun and contributes to the big electrical peak. One idea is to paint the roof with titanium white to cut down on the sensible heat load.
The idea I have is to try to smooth out the electrical peak load by letting the AC run more at night and run a little less during the day, and to let the sensible-heat temperature cycle up and down during the day, but to have some combined measure of heat and humidity remain constant. Instead of maintaining a constant temperature to try to maintain a constant indoor dewpoint.
This system would 1) have it cooler at night to make sleeping easier -- I can stand it warmer during the day, 2) smooth out electrical peak demand, 3) more efficiently remove humidity averaged on a 24 hour basis because humidity removal efficiency goes down if the AC duty cycle goes up during the day and you are pulling the indoor humidity below 50 percent.
Carrier makes a rather expensive ($200 plus) Humidistat product that controls the AC to both temperature and humidity targets. A cheaper solution for me is to use a setback thermometer which lets the temps go down at night and go up during the day, and to only start lowering temps at sleep time. A typical setback unit has night, wake, day, and return times -- I may go for 75 night, 74 wake, 77 day, and 78 return (the thermal pulse from the sun shining all day makes it through the house by evening, and at 78 the AC will be cycling to lower the humidity anyway). I also use an electronic humidity gauge and dial all those temps up or down a degree or two to get about 50 percent RH).
I recently got back from Disney World. At Epcot, in Innoventions, they have a "home of the future" tour. Most of the stuff is fluff stuff that if you read sites like slashdot, you would already know about. However, one of the interesting things they show is a plumbing system that takes the hot water going down the drain of your shower and uses it to heat new water going into the shower. I think that she said something like 30% efficiency.
Maybe you don't have a choice, but I do.
My water comes from my own well in the front yard. I'm in control of it. If I want to know whats in it, I have to test it. If I want to kill bacteria I have to buy the clorine, and follow directions. If the pump breaks I have to fix it (more likely pay to fix it, the pump is 200 feet underground).
My sewage goes to my own septic tank. I have to pay to get this pumped every few years, but there are several different companies that will do this. When the lines freeze I have to figgure out how to thaw them. (Stupid installer can't install lines that don't freeze... I'll try again to correct that next summer, but it isn't as easy as it sounds)
If you have a choice, get city sewer, it is much cheaper, and a lot less hasstles. I prefer well water, but some will disagree with me, it is a matter of taste. Most of the people who disagree with me have had problems with their well though, something to take note of.
Even if you have city hookups, you have choices. You can vote for someone who won't maintain the plant for instance. Closer to home, most city water systems could use further treatment. They give you safe water, it may or may not taste good. It may or may not stain your clothing. It may or may not need extra soap to clean clothing. It may or may not have sand mixed in. And those are just things locals watch for, your area may have other things to worry about.
Most people don't think of any of the above though. Just turn on the tap and there is water. (at least where /. is common, most of the world's population doesn't have that advantage) I don't normally think about it either, but once in a while I have to.
I have a fairly paltry income, I was willing to do anything to cut back on expenses to make my daily life a little easier to live.
Started with the electric bill, did the obvious things, knocked the thermostat in a direction that'd keep the costs down. Replaced all the bulbs in the house with florecents. Switched to more energy effecient devices and appliances. It helped, but didn't make a real dent. My problem was heating and cooling. I live in a location with all the seasons. Very hot, very cold.
Then a co-worker inspired an idea. He faught in Viet Nam, told me bout how the guys rotated back to the world and stopped in Hawaii for refueling. All the guys in combat were so used to the hot humid jungle that the 88F weather of Hawaii was just too cold for them, they all had on leather jackets trying to beat the chill.
It was then I realized, that to a degree, my battles with TVA were more easily won by conditioning. All these years I had been spoiled by AC and electric heat. So I did a little experiment this Winter.
I vowed never to turn on the heat unless there was a chance that the pipes might freeze. Went and bought a coleman sleeping bag and a bunkbed at a thriftstore, kept myself closer to the cieling and snuggly in my sleeping bag. Kept very warm at night, during the day I'd burn a few candles just to take the chill out of the room, wore long sleaves.
My electric bill went from 270$ a month to around 30$.
Success through suffering. But the experiment worked, now I can run around in shorts when it's 38F out and it's not big deal to me.
How will I fair during the Summer tho? Many people die in the South from heat stroke, so I'm a little concerned about that. I really don't wanna die or get sick to save a dollar. So I think I'm going to do some zone cooling, reasonable AC set on 80 and lots of fans.
The methods illustrated in the story would have been tempting, but I'm a renter. Not a whole like I can apply to the living structure without violating my lease and being homeless where it's gonna be really cold out.
I stayed at a place like this in Australia. It was a vacation house in the Kangaroo Valley, about 2-3 kilometers from the nearest paved road and 2.5 hours south east of Sydney. It's apparently fairly common in remote areas, not just in Australia. The toilets were low flow, though not much lower flow than the rest of Australia. However, the water was not recycled for drinking water in this case.
There were two tanks - one caught the majority of the rain water for fresh water, and filtered and chlornated it. The second caught the sewage, again chlornating it and filtering it. The second tank was used for water plants and landscaping and cleaning.
In the island nation of Burmuda (and other low-lying ilsands which lack freshwater) all homes collect their freshwater from their roof as well. For fire fighting, the tanks must have an unlocked access door for fire tucks to pump water out of the tank.
Learning things like this make you really appreciate the availablility of fresh water. And staying in the Kangaroo Valley in January makes you really miss HVAC. =)
Actually, the single most worthy project would be simply buying a new refrigerator. They are the #1 electricity consumers in almost every household, because they run 24x7x365, and are never thrown out until they completely fail(after years of working below the already mediocre factory performance). Newer refrigerators are MUCH more efficient than those made 5, 10 years ago. There are even models that are so efficient, they can be run entirely off solar power.
Wanna reduce your electric bill, but can't replace your fridge? Leave enough space behind it for airflow, and vacuum/dust the coils, especially those under the unit. Oh, and properly set the controls; buy a thermometer and adjust until both compartments are cold -enough-. The freezer control, by the way, doesn't control the freezer compartment temperature- it controls the RATIO of cooling between refrigerator and freezer compartments.
All in all, even if you buy a new fridge, it could end up paying for itself in a year or two in saved electric costs. Oh, and slowly switch your lights over to fluorescent bulbs, wrap hot water pipes in foam insulation, put sealing inserts behind outlet plates+switchplates, etc. In the winter, cover windows in rooms you don't use with the window insulation you can buy at the hardware store. Find out the R-rating on the insulation in your walls, attic, etc; old insulation can be horrible compared to the latest new stuff(which can often be "blown" into place, install is a cinch). Got an old furnace? Get a new one; they're also a thousand times better these days. My folk's new gas furnace is so efficient, its exhaust is a 2" PVC pipe that is barely warm to the touch when it's going full blast...
Last but not least, turn off the damn computer when you're not using it, get an ISP account with webspace instead of running your own webserver, etc. I worked it out once...100-200W over 24x7x365 equals a LOT of money per year!
Please help metamoderate.
The main unit in this case can be a PC which uses devices not unlike the control units (except without servo control) and which have a power supply for the other devices, as an interface to the system. And, there are no big expensive components which are difficult to interface to because they are either on or off. Heating devices have a thermocouple which will provide a few mA of current to let you know when they are ready, you can pull that signal and then you just connect it through to another wire to turn on the heater. (I assume that AC is similar, though obviously not identical.) A thermostat is an amazingly simple device, especially electrically. Those devices will (at least internally but also externally) work like this basically forever because there is no reason for them not to.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
When I bult my house I used Wirsbo(tm) tubing under the hardwood flooring upstairs, and in the concrete slab downstairs. It is set up with zones, digital, 7 day thermostats, etc. The floors are always warm, any backup heat is from a pellet stove. All DIY. It is very comfortable.
The heat for the infloor system is from standard water heaters. Since the water heaters are downstairs, I don't need to turn on the thermostats for pump control - simple thermosiphon will cause the hot water to flow thru the system in the upper two stories.
The system is simple and convenient. If power goes out I still have heat from thermosiphoning.
It is possible top retrofit homes with this system, either with baseboard radiators or running the tubing between the joists (plus some drilling to get to each joist bay) as long as the crawl space is available.
There are other companies besides Wirsbo that produce this type of heating system/product.
When you are ready to build/buy your own house I recommend comparing HVAC and infloor heating. Look at "Fine Homebuilding" magazine for ads and articles, they are at the obvious web site.
To make my heating system more viable I used foam insulation for R-50 in the walls and R-60 in the roof. Double paned windows and a 5 foot overhang to reduce summer heat gain (my outside walls are 11 feet high). If the are more than 8 people in the house at a time I need to turn all the heating off, as the heat thrown off by the bodies raises the inside temp.
All in all a rather pleasant solution to the heating/cooling system.
Since I live on the northern California coast I don't need cooling. Average year round temp is 55 degrees F.
If you need cooling the system could be adapted for that. To cool the house you only need to cool the circulating water, a heat pump would the best solution.
A few months ago, I bailed on a seven-year stint as an active HVAC contractor in Florida; I love this project.
But I am glad I don't have to answer the radio shout for help from the poor on-call technician who gets a look at this equipment for the first time at 0200 on a Sunday morning. If something breaks on a system like this, and the geek that built it is gone, then things will likely progress as you describe: The hardware changes will be undone in a few hours, returning the system to a state understood by the servicer, even if the problem is as simple as a mechanically broken servo link. Many of the HVAC techs working have trouble using their VOMs efficiently on the high voltage sections of the system. For these guys, controls are mysterious scary voodoo magic. For such a cool system to survive its inventor it'll need killer documentation, easy to find and comprehend, and hard to lose.
The article mentions the Trane XV1500. We had a bunch under our care; they were wicked good air conditioners. They stopped making them because the average service tech was helpless to make them go when they broke, so they tore them apart and tried to make them work in a more simple way...which was not possible with those systems, as the compressor was a frequency-controlled DC motor. Much unhappiness for tech, for homeowner, for service company, for Trane. So now they make a condensing unit with two old fashioned compressors, and stage those. They still get butchered, but at least coldness can happen on an emergency call on the 4th of July weekend.
Depends very much on where you live. Here, in one of the Denver suburbs, semi-arid climate, the following rules come into play:
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No new cesspools or septic fields allowed.
Inside the city limits, developers are required to connect to city services.
If you have an existing septic field, and want to subdivide a portion of your property, you won't be given permission until you shut down the field and connect to city services.
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No new wells allowed.
If you decide the septic field is not worth the trouble and want to connect to city sewage, you'll have to shut down an existing well and connect to city water also.
Outside the city, wells have a different set of problems.
Shallow wells are not reliable.
Deep wells into some aquifers are regulated by the state now.
Up in the foothills, it is not unusual to have to drill 10K feet in order to establish a reliable well.
Pumping water that far is expensive.
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Collecting rainfall and storing it is, in general, illegal.
Senior water rights to runoff from your property are held by someone downstream.
Trust me on this one, buying water from the city is cheaper than trying to find all of the people that might have rights to your runoff.
Since some of those rights will be held by the local municipal government, who will not be shy about taking you to court when you try to install a cistern of any size.
Water law in the western US is bizarre, to say the least.directly tie-in to the temperature zoning system featured in this Slashdot posting.
The temperature controller is an *excellent* idea, I think I'll take a look at incorporating it into my house.
Here's my little (non-computerized) ecological project: a gray water toilet which recycles water from my washing machine.
Fire and Meat. Yummy.
Hong Kong is kind of unusual (at least, I've never heard of this being done anywhere else) in that they have two different plumbing systems. Toilets use salt water, and the rest of the system uses fresh water. This is because they have to buy their fresh water from mainland China, and it severely reduces their costs to use salt water for their sewage.
$45 per U Colocation Special
Come on, a cheap mini-itx with a decent processor can be put together for less than the cost of a simple digital thermostat, let alone one as complex as a multizone controller.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I've considered that, but you are ignoring the most expensive part of all that: my personal time in setting that up and getting it balanced out to where my family and I find it usable. It is the difference between a TiVo and MythTV: where I am concerned I would choose the latter, but because my family gets put into the equation I go with the former. Could I have gone with a Radio Shack learning remote? Sure, but throw my then-6-year-old into the mix and I went for the Pronto so that they don't have to remember "AUX1 is for this, but you have to hit AUX2 anbd power after that." I don't want the family to have to reboot the system because they're friggin freezing and some stupid patch hasn't been put up on a site yet. Besides, a lot of the digital thermostats from sites like SmartHome integrate into MisterHouse which runs on Perl and doesn't bog my server down. Best of both worlds.
"Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
Another option in high humidity locations is to just get a de-humidifier.
If you own your home, consider getting awnings, trees, or some other source of shade for your western exposure.
Also, try and create a cross-breeze through the house from the bottom of the "cold" side to the top of the warm side. Double-hung windows and attic fans are both good for this.
Zoning's benefit is that you don't over heat/cool areas that aren't occupied.
Two days ago I paid my bill, 250 EUR. Given that I live alone, with almost no electrical devices turned on, that is even considered a low bill here in Belgium.
Average families with two children can expect 300 EUR to 500 EUR bill each year.
And of course, there are places like Mount Nebo, just outside Brisbane (Australia) which don't have town water connected. Rain water/tanker delivered only. So you have to do all of the above and buy huge water storage tanks. Not everyone even in the first world has what to most of us are "basic" amenities.
it's not about the karma, it's about the whuffie
Actually, I work for a HVAC wholesale distributor and I can get a Honeywell Chronotherm IV Single Stage Heatpump for 63.62 USD. The guy in the article 'vt' was using a Honeywell Chronotherm III. I don't know anyone who could build a micro tower for less than that.
peace,
-Grokent