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For non oil burners - how to get hot water

Post in 'The Green Room' started by wannabegreener, Jan 5, 2012.

  1. Highbeam

    Highbeam Minister of Fire

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    base of Mt. Rainier on the wet side, WA
    I have no basement or garage so the water heater would be in a hallway or other heated living space. The sound levels appear unacceptable. Too bad they couldn't do a mini-split style outside unit.

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  2. begreen

    begreen Mooderator Staff Member

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    South Puget Sound, WA
    I also went to Lowes website for reviews. There are a lot of compressor failures being reported. I've decided to stick with resistance electric for now.
  3. woodgeek

    woodgeek Minister of Fire

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    SE PA
    interesting.....

    My location is a large attached garage which already has a dehumidifer, so I wasn't worried about noise and figured I could save. I figure it will run conv in the winter, and think my ROI will still be decent.
    I had also decided that the GE unit FHR was too small for a family--that's why I want the 80 gal Voltex.

    I guess I'll get the extended warranty!

    As for the questions....the recovery on HP is supposed to be ~5 hours, not much longer than for a conv elec tank. It seems that when the compressor fails, it reverts to the elec coil---you are not w/o DHW until the repair. I wish my oil boiler could do that.

    When I quote out/pull the trigger....I will post.
  4. velvetfoot

    velvetfoot Minister of Fire

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    Loc:
    Sand Lake, NY
    I'm thinking of adding a pellet boiler and maybe also use that for hot water.
  5. EJL923

    EJL923 Feeling the Heat

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    Western Mass
    Well im a little confused with all the acronyms, but the efficiency goes down on the heat pump when the ambient temp is below 50°F, and not even recommended below 45. This would rule out garages and some basements.
  6. woodgeek

    woodgeek Minister of Fire

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    My unconditioned garage runs >50°F about 9 mos of the year. As I understand it, the controller will automatically switch from the compressor to the coil and back again as needed when the ambient temp drops too low. My estimates suggest that running 'conventional' for 3 mos of the year will cut my payback, but not much. The operating cost should still be half that of a conventional elec tank, and about a quarter of my current tankless coil/oil boiler combo.

    Assuming I can find someone to install a 400 lb unit!
  7. GaryGary

    GaryGary Feeling the Heat

    Joined:
    Jul 12, 2010
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    Loc:
    SW Montana
    Hi,
    OK -- after 6 pages with no mention of solar, I thought someone should bring it up :)

    Solar might work particularly well in your case, since a solar water heater could provide essentially 100% of your hot water during the part of the year you would not be running your oil burner except to make hot water. I've heard from several people who have wood winter space and water heating and use solar water heating in the summer and it works well for them.

    This is my current system: http://www.builditsolar.com/Projects/SpaceHeating/DHWplusSpace/Main.htm
    It provides both domestic water heating and limited space heating.
    It can be scaled back to do only solar water heating.

    Very simple -- the only moving part is the collector circulation pump, which is a regular, lasts forever, HVAC circulator (Grundfos 15-58).

    Very cheap -- the water heating only DIY version can be built for $1000 with just about everything coming from Home Depot. We got a $500 MT rebate, so total out of pocket was $500 -- a less than 2 season payback.

    Gary
  8. mr.fixit

    mr.fixit Member

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    Loc:
    west central wi.
    +1 Gary
    My solar HW system (based on your design)is still working great after 3 years.
    I also put in my own PV system last year.
    I have to stop looking at your website! Next thing ya know I'll be buying an Elec-trak!
    Thanks for all your free information that you provide us.
  9. woodgeek

    woodgeek Minister of Fire

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  10. steviep

    steviep Member

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    Loc:
    southeast NH
    During the winter I have a stripped out water heater next to my woodstove that heats the water to 110 / 120 degees. It preheats the water before going into the gas water heater. For the summer I plan on building either a system like Garys or a simple Batch heater.
  11. wannabegreener

    wannabegreener Member

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    Loc:
    Southern NH
    I have had a solar company come in and give me a quote. They want to put up 2 flat panels and they claim I will save only 120 gal of oil per year. This seems crazy especially since the payback will be over 15 years. I'm having a couple of others come out to give me a quote (money wise and oil saving wise). I have heard from a poster in Maine that his payback will be about 6-7 years. That looks a lot better than 15 years.

    I also run a dehumidifier in the basement all summer and from my guess, it is costing me $35 or more each month. So, if I could put that electricity into a heat pump I would essentially get hot water for free. (after the purchase of the heat pump).

    Thanks for the point to your web site. I'll take a look at it.
  12. woodsmaster

    woodsmaster Minister of Fire

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    N.W. Ohio
    Check out do it yourself solar. If your handy you may be able build a couple solar panels and install them yourself for a lot less.
  13. Rhone

    Rhone Minister of Fire

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    Nov 21, 2005
    Messages:
    824
    Oh my god my post was lost. I guess I been away too long.

    I'll just make the response quick then. I started with a tankless oil system, it kept 3 gallons hot in the coils so there was always instant hot water but supposedly also on-demand so there wasn't much loss. It had a lot of loss, as it didn't shut the intakes ever so when it wasn't running my basement air would be sucked into the unit, pass the coils cooling them right down, and go out the flue. It always cycled on/off. I was using 230 gallons/oil per year even though I was shutting it off during the day and night.

    I purchased a 3 panel solar system from http://www.radiantsolar.com/solar_domestic_option.php including the tank. I hooked the tank to electric while I poked at the solar tubing in my free time. To my surprise, my electric bill only went up about $25/month (I pay $0.23kWh) so it was a huge savings. But, as others have pointed out there's no standby losses. The install was pretty easy, I am a DIY.

    I got the solar hooked up (I live in VT) and I shut the electric off so I was just 100% solar for my hot water and from the 2nd week of January to the 2nd week of December I only had to turn on the electric to the tank 11 times. Compared to oil, it was a huge savings today. 230 gallons of oil saved at $3.70 per, that's $800/year! Compared to electric, I was only paying $300/year switching to the electric tank and saving $250 from solar so the payback is 5-10 years. In the end, with rebates, I ended up paying $2,500 after rebates/credits and I did it myself but I did some stupid stuff like, used special $6/foot insulation and 1" type "L" pipe which is not standard so it was so expensive. I should've just gotten regular black foam insulation (for inside) and 3/4" type "M" pipe (which is standard and cheap). Plus mistakes like, when I dry fitted my 1" connections there's so much friction I couldn't remove them not even with a hammer or pliers and torch! I had all my panels dry fit together in 2 arrays ready to solder then couldn't get it seperated to solder I had to cut out all my fittings and redo it all. Just using 3/4" type "M" pipe and regular foam probably would've reduced my cost by $1000 at least. I do love solar and glad I did it.

    I'm not a fan of evacuated tube solar nor photovoltaic, let me know if you have questions. Thanks
  14. otsegony

    otsegony Member

    Joined:
    Dec 19, 2006
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    32
    I posted previously in this thread about the GE HP hot water heater, but I will provide a bit more information based on another month's usage.

    - Electric usage is still within a few kwh of last year's bill. I attribute this to the fact that I was using my oil-fired boiler last year and between the burner and the pumps it used a fair amount of electricity.
    - Operationally the HP water heater works very well. The 50 gallon capacity has been more than enough for my family of four (two adults, two teenagers) with no shortage of hot water noted even after the morning shower routine.
    - Having both the HP hot water heater and the wood stove in the basement is working well with only a moderate increase in wood consumption being noticed. However, this past couple of weeks I've been away and unable to tend the fire as I usually do and I've run into a part of our wood supply that is not as well seasoned as the rest. The result is that I've noticed that the cool air coming off of the HP water heater has made the cellar cold and it is harder to heat up with the wood stove. The lesson learned is to keep the wood stove burning hot and strong and double check the wood supply before bringing it in.

    I hope this is useful information.
  15. wannabegreener

    wannabegreener Member

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    Southern NH
    Just signed a contract for solar dhw. Waiting for all of the rest of the paperwork including the nh rebate papers. Not sure when it will be installed, but I can't wait for the savings to begin. From another thread, I mentioned that I had the nh energy audit done. With the work they did, they claim about 130 gal of oil savings and this should save me another 200 gal. (I hope). If these numbers are right, I will be below 300 gal of oil and 2.5 cords of wood per year. If I can get some of my wood heat to the second floor, I should be able to reduce the oil usage a little more and maybe not use any more wood. The room I have the fireplace insert in is usually between 76 and 80 degrees. I have been keeping records of oil usage based on delivery so it should be easy to see what is being saved.
  16. billb3

    billb3 Minister of Fire

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    Now you'll be cursing cloudy weather. ::-)
  17. wannabegreener

    wannabegreener Member

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    I figure my well water is probably around 50 so even when it is 70 and cloudy, it can preheat my water to around 70 and I gain 20 degrees just from the warm weather.
  18. wannabegreener

    wannabegreener Member

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    Southern NH
    Just wanted to give an update. I got my solar installed in April 2012 and got an oil delivery on April 27th. My next oil delivery was November 14th and only for 66.2 gallons. Without the solar, it would have been 190 gallons for hot water only, plus a few more for heat. I also hooked up a timer to count when the hot water zone was open. From this, I calculated my usage for these 7 months to be about 15 gallons. This means solar saved me 175 gallons in the 7 months of usage. I also checked my solar collector temp on a sunny 37 degree day with a good amount of wind, it was regathering 140 degrees and the solar pump was cranking. I can't wait to se what the complete year's oil will be.

    So it looks like solar is a decent choice for southern NH.
    milleo likes this.
  19. woodgeek

    woodgeek Minister of Fire

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    great. system details??
  20. wannabegreener

    wannabegreener Member

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    Loc:
    Southern NH
    System includes

    2 Wagner solar panels
    1 80 gal superstor single coil HW tank
    1 pump to pump the antifreeze solution to the panels
    1 pump to circulate between the solar tank and the boiler HW tank.

    Basically, when the solar panels are warmer than the middle of the solar tank, the solar pump will run. The speed is dependent of the the temp differential. If the solar tank top temp is x degrees higher than the boiler HW tank, the circulator pump will move the hotter water from the solar tank to the boiler tank. When the house calls for HW, it comes from the boiler tank. The boiler tank gets filled from the solar tank so if the water coming into the boiler tank is hot enough, the boiler will not turn on.

    I put a timer on the circulator pump for the HW circuirt for the boiler. It counts the number of hours it runs. From mid April to mid October, it ran for 25 hours and my nozzle is a .65 nozzle so I only burned about 16 gals of oil for those 6 months.

    Hope this helps.
    woodgeek likes this.

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