HRU - Not what I consider the best value especially for a homeowner. I'm a 57 year old retired , at 46, scientist who worked for many years in the field consulting in analytical materials labs. I worked with lots of instrumentation and it all had various systems to move heat or do various things with materials and electricity. I also was exposed thoroughly to developing methods to test how plants who make things run their production lines. Anyway I say this kind of product doesn't look like a good value to me for a couple of simple reasons. 1. The initial cost . If it's $100 or less well I can't complain. It's only a box with a tube basically. So what you pay is money that's out of service for you and not working elsewhere. 2. The freon has to be plumbed into the unit. This is more cost and introduces something I would never do in a laboratory unless it had more gains than this ... A leak would ruin the A/C unit and cause downtime plus the cost of the A/C unit. This isn't a good plan. If the unit came with the A/C mfg design I would consider it a part of the method the plant uses to build the entire unit. But aftermarket just does not ever make much sense to me unless .. there is no other way. I think there's another way. 3. The efficiency ratings I read are 10%. That is exactly the gain I got when I water cooled my coils on a home refrigerator unit. I got a similar reading when I cooled a regular home A/C unit with water. The amount of water to cool my parent's 4 or 5 ton , 1935 (it's still running) A/C unit is about 6 gallons / hour. The amount of water usage is very low. So I say this: Use water to cool your coils. You'll lose the heat energy to the water if the water's thrown away but assuming it's at home the water can be used so it's not wasted. And if you want some heat that's in the water then plumb a regular $50 heater core or small radiator on the cooling coils of your A/C unit. If the size doesn't fit .. yes you'll have to reconsider the design. Maybe you can only run 1/4" copper tubing firmly attached to the coils .. But you'll be running water through the secondary coolling system .. not freon. And a failure of that system won't affect the safety or even the operation of the A/C .. as long as you haven't blocked the air flow. If not for the probable high initial cost . I'm guessing $400 and the plumbing into the freon line I would be positive towards a unit like this. Which I am via the design ideas above. 4. Another method to cool coils without putting water directly on them is to use a 'swamp cooler' design around the coils where air comes in to pass over. I realize this won't work as well in Houston or Florida. However air that is 90F and wet will still carrry away more heat than air that is dry and at 90F. Any gain of humidity with pads and a bit of water over them will give you some gain of efficiency. And there is the fact that your compressor will run longer.. ours has been running in 100F Summers since 1935. And I personally know it's been running since 1975 without any maintenance or downtime and the costs of running it are low. This will occur with both plans of my idea or the HRU. One things I don't quite get in the marketing is the absolute heat temp of the output of the HRU. If the compressor is to run cool it 's going to need cool water. The outflow from the unit we have , from 1935, is at about 15F above the incoming temp. While this would help to preheat water I would not expect hot water nor would I want hot water. I 'd want my compressor to run as cool as possible. You decide. I have not run extensive testing. I'm using mostly experience but not any calculations on the HRU except the specs I've seen. I have an idea. Seriously. Why not put a 100 gallon tank of water in your car and use your engine to heat it to about 180F as you drive around? Then when you get home you'll have a day's worth of very very hot water 'for free'. Seriously. This is the exact design used for carpet cleaning vans which use engine heat to heat the steam either preheating or fully heating. I don't know how they can get to 212F without the engine overheating but they do , for about $3000, offer a heater that runs off the engine and heats the clearning water. why not do the same and then 'plug in your water tank' when you get home for an whole night's worth of hot water ? There are ideas out there. They're not dumb. Just weigh the cost and risks. Andre

Two things, one, I want John to be my dad!! Two, I had a friend who's son got kicked out of his dorm for having a pocket knife. And he didn't even remember that he had it. That was Temple University. They had to kick him out because they had a zero tolerance policy. It was just for one semester. He had to move home and commute. Weird but true. That was about 8 years ago though. Totally cool that some dorms now have communal kitchens! I lived in one for a summer semester but it didn't have a cafeteria. I totally melted the carpet because I was carrying a pan back from the kitchen to my dorm to eat it and I set it down to open the door and didn't realize it was hot enough to melt the carpet! Nice brown circle burned into the carpet by my dorm door! I loved that arrangement back in the day, but yes, college cafeteria food had some a long, long way since then, some places around me are even doing the whole "local" produce thing with college gardens too. Lots of veggie options that I would have never dreamed of. I had to exist on broccoli cheese casserole back when I lived in the dorm. My dorm room cooking consisted of peanut butter and honey on saltines. But I went to the farm market and got fresh ground peanut butter and comb honey! Ramen in the hotpot and tea, what more could a college student ask for!

As a resident of the Great, Benighted North-east ... let me ask ... anyone for conservation of energy? When my power went off - I went to my provincial gov't. rep's office to give him H-E double toothpicks. Due to traffic tie-up arrived 5 min. after closing (I think) but they were open. Couldn't afford to give him too much of a piece of my mind - conservation of mental capacity, don't you know. En route home, directed traffic for a while at substantial intersection in rush hour. Several said, "Thanks" or waved - one said, "Get off the street"! Several civilians in Toronto did likewise, we're told. Visited 87 yr. old uncle living alone after recent death of wife who, despite painful back, hip, leg insists on keeping some beef cattle, got candles out for him, showed him how to use battery radio (that he didn't know he had - I'd stayed with him for a while after his wife died last year). Glad I recently bought batteries for my $1.00-at-garage-sale radio. National broadcaster ran advice about need to turn everything off that we could, to reduce surge when reconnecting, and province-wide phone-in to share ideas. I pulled fuses from water heater connection - haven't replaced them yet, as they say we need severe conservation measures, at present, to avoid rolling blackouts. Shaved in reasonably hot water Sat. morning. Haven't bathed since - imagine I smell by now (but I live alone). Hope I don't suffer blackout right now, or I lose all my writing here. A guy called about 10:30 to cry about 400 lb. of meat that he had (perhaps fresh? which would mean that his window of opportunity to save it would be reduced over if it were frozen). I began calling with suggestions for him, in dark for a while until power returned about 11 - I was without for 7 hours only - plus a short interruption later. Line busy til 4 a.m. I suggested he find a van or pickup, load his freezer, put meat in, take substantial lunch, head for nearest rural area, go door-to-door asking for generator. I was sure he wouldn't go three miles till found farmer willing to fire up generator, freeze his meat. Lunch so he could stick around for repeat every half day or so, as needed, till power returned at his home. Lunch optional - most (traditional) farmers wouldn't see him go hungry. Twice in recent years I took portable generators to areas blacked out due to ice storm - once 500 miles away. I goofed Thursday evening - didn't get on phone to friends seeking generator. When I did, Fr. morning, couldn't locate one. Think I should try to compile database of generators possibly available and persons with major freezer stock - homeowners, small stores, etc. not hard-wired, with 220 volt systems, etc. in preparation for such an eventuality in future. One generator can travel from site to site to serve possibly a couple of dozen freezers - perhaps half an hour each, twice daily or less, depending on outside temp. Invite those of you with time, energy available in your area to do likewise. We've been asked to shut down all unnecessary power consuming systems, e.g. signage, billboards. Local grocery in plaza shut down lights in parking lot. Many non-essential govt offices told to stay closed and asking factories and commerce to try to keep consumption to half of normal usage for about a week. Can't understand how Times Square figures it should be lit as usual. Do they want to be shut down - again? They say that it's to be hotter and more humid during the next few days. Hope you don't suffer Benightedhood too often! joyful guy

We live in Texas also. The last house we had, we ran the temp at 81 constantly and the electric bill was still $300 one August. So, we paid $15k and replaced the entire A/C, conden.. ALL of it.. heater too. The only thing we kept was the ducting. We had all the ducts re-sealed, house pressure tested and sealed (even the electrical sockets were tested for leaks). We replaced the external doors with better ones, and we had the ENTIRE attic, including over the garage, sprayed with R49, more than required. We had radiant barrier sprayed into the entire attic as well. The loan cost us like $105 a month. The electric bill dropped to about $120 a month on the hottest days and that was with us running the temp at 74-76. In the winter, we had the electric bill below $60. Best money we ever spent. R