Tom M's posts

Terry, if this is just a getaway cabin, how big of a fridge do you need? You can purchas a 12 volt thermo electric cooler pretty cheap. Need more room, buy two. You can bring ice with you or you can make ice with solar.
 Also sounds like you need a water barrel......then think solar hot shower....possible DC pump and water tower...composting toilet or flushable toilet with waste catcher....then  methane gas for your gas supply......

No problem Larry. Any gain you can get is better than a loss, and hopefully your gains outnumber your losses.

So 850 Watts input at 12 volts...around 70 amps....usually the t-stat for an electric hot water heater is used in conjuntion with a 30 amp breaker, (double 15 amp breaker in the fuse box.) I cannot say for sure what the ratings are for the existing kenmore t-stat contacts, so you'll have to double check that yourself.
 There are usually two 4500 or 3500 watt elements in an ordinary HW heater, but both do not normally operate at full throttle at the same time. 240 v at 30 amp..7200 Watts.....so there may be an issue using the installed t-stat.....probably best to wire the element directly with a dedicated breaker or switch rated at the 70 amps.
Also, if the t-stat shuts off the power supply while the diversion power is coming in, the power will have no where to go and may cause some problems......a dedicated breaker would be a better safety backup...

Larry, is this tank used exclusively for the diversion load? Do you have a second HW tank for your main domestic hot water? Does this Kemore tank preheat water going into another tank? What is the diversion load coming from? Wind, Hydro, PV? How much power is going into the element? What is the power rating of the element, eg. how many Watts? How many gallons in the Kenmore?
 Main issue is with the safefy portion of the tank. Most electric tanks have a breaker that works off the temperature in the tank. If your new element is wired to this breaker and it turns off at some point, due to excessive hot water, you may cause damage if your system goes into diversion mode and the circuit to the element is off.
 Which is why knowing how much power is entering and how much water is being heated needs to be known. 
 Also check the rating of the contacts of this breaker.
 You could by pass this breaker and wire the element directly if you can calculate how hot the water will get. As long as it would stay below 160 you should be okay.   
 Hopefully there is a T & P relief valve on the tank along with a vaccuum relief for safety.

If all works out, and you get the freezer going, make ice while the sun shines. Then put the ice in the fridge to reduce running time.

Can I assume 120 volts and 5 hrs sun and/or 5 hrs run time?
 So 1200 Wh /( 120v x 5hr)= 2 amps
 or 1200 Wh / 5hr = 240 Watts
 Does the fridge only draw 2 amps?

freezer 1000 /(120 x 5) = 1.7 amps?
  1000/ 5 = 200 Watts

If this is true then the battery stuff and  inverter should be okay.

Then, 130 Watt panel for 5 hrs, around 600 Watt hrs. So to cover your power needs of 1200 + 1000, you would need 4 of the panels. One more to ensure enough power for storage. Current from these 4 panels would be around 40 amps so the charge controller should be okay also. 

Eric, each inverter is different, some offer both grid tie and off grid capabilities. Best to compare and research some of the inverters for sale here at AltE. You can download manuals also for later reading and comparison.
 You should size your inverter based on the maximum power consumption of your appliances. Just figure power needed if all appliances are on. Most inverters have a surge power associated with them to compensate for start up power draw. Once you know the maximum power draw and/or max surge, size an inverter accordingly. At least 25% over what you need for a safe start. Future power should also be considered.
 Any extra or redundant protection is always welcomed. Most inverters have built in fuses for protection. I assume that electrical interference is what you are talking about. Of course things like cold, heat, dirt, water and such should be avoided.

Peter, hard to tell without the power demand of the fridge and freezer. How many daily Watts and/or Amps and at what voltage?

Eric, it can get confusing. Especially when dealing with units associated with electricity. Just remember it is no different than any other calculations using ft^2 and such. Just know what the units are and what they become when combined, eg amp x volts = watts, and trust them. Follow math rules and the answer should come out the same no matter how you calculate it. The addition of hours can also make it confusing, which is why sometimes it can be easier to do your figuring based on an hours production, then do the time thing last. Glad you got it.
 Hopefully you also learned why a lot of people do not go solar when it comes to PV. If someone personally cannot calculate a system size properly, then find out that the system they need is way to big and expensive, they often times opt out. As with most anything, dedicated PV systems can be beneficial in some cases and in others not. 

Okay, you need 84 AH from a panel that needs to produces 24.7 amps. Unfortunately, one, 120 Watt panel only produces 10 amps operating at 12 Volts or 5 amps at 24 volts. (you say 34 volts, using that, 4 amps.)
 So you would need 3, twelve volt panels to cover your needs. (or 5, 24 volt ) Now figure those numbers into your calculations.
 Or just believe the other two post and learn from their examples. There is also many calculators out there to help you. One here at AltE.

wrong. What is the panel voltage? Try finding how many daily watts are needed first. A x V = W. Then how many panels are needed and then determine A output using sun hrs. More amps : more panels. Make sure you realize your output voltage is different than your operating voltage. 

James, a cheap alternative for 12 volt lighting is to use automotive bulbs such as break lights. They usually only draw around 1 amp and give off bright light. I've seen them used in marine novelty lights. The best thing is that they are cheap and readily available most anywhere, even free at junk yards.

Think it's our old friend Carl and his cronies blowing hot air again?!

Eddy, if you plan on changing over to a DC pump, specs for that pump would be the first thing needed. Then figure power needed just as I figured previously. Then you can figure cost by looking at product pricing here at AltE.

 z

....as long as they are not permanently fixed then you can move them and adjust them year round.....

Eddy, first 1 HP is around 750 Watts.

 Running at 120 Volts the pump draws

  750 W/120 V = 6  amps.

If you run the pump for 5 hrs at 120 V then you would need
 
  6 Amp x 5 hrs = 30 Amp hrs

Now if you have one 120 Watt, 12 Volt, 10 Amp solar panel;

Over 6 hrs you produce 60 Amp hrs at 12 V(60A x 12 V =720 W)
 
This translates to 6 Amp hrs at 120 V (6 A x 120 V =720 W)


 So therefore we need five, 120W solar PV panels to cover our demand of 30 amp hrs at 120 V
   (6 Amp hrs x 5 panels = 30 Amp hrs)

Then of course batteries, wires, inverters and controllers etc....


Best to determine how much water is in the pool and how many GPM the pumps handles. Figure how long the pump has to run in order to filter the pool twice. Basically, try to reduce operating time in order to save electricity. Filter the water when people are in the pool stirring it up. Cover the pool to keep debris out. Install a timer. Keep the filter clean.....
   

....iron could be coming from your tank.......rust?

Max, as Thomas figured, the 60 W isn't that much power when heating water. If you had a greater power source it would make more sense.
  The air heater that you have now is probably the better option. If the heater is located in the same room as the water heater, that may heat the water just as much. Or, you could even put a coil of tubing inside a piece of ductwork to preheat ,or the whole tank in an insulated box, along with the resistive air heater.

Jon, any type bracket would work, or even wood, if your not afraid to screw or bolt into the frame on the panel itself. The frame is just a piece of metal, nothing special.
  Fancy clips sold for money and warranty worries are just more hidden costs that keep prices up.

...or you can purchase a small inverter here at AltE for around 100+ bucks (Go power 1000 Watt or similar). Then you can just plug the differential controller into that. Any deep cycle battery, or 12 volt battery should work. Consideration of how long you need power for should be a thought, as Thomas A. suggested, if indeed power is lost for a long time. Otherwise, the battery can be recharged using a regular battery charger when AC power is restored or use a PV panel and cheap charge controller for year round charging and operation of your HW system and emergency lighting. You may even have enough power from the inverter to operate your boiler for home heating during power outages.

Thomas, if the pump shuts down from being unbalanced, as I also mentioned earlier, then there must be some factor causing this unbalance. More than likely it is caused from wear due to friction and/or debris in the fluid building up on the impeller.
 As mentioned also, recheck your modern computer fans, they too run on magnetism, no bearings, and fail in the same way.
 Though you don't seem to believe it, a small amount of grease should help the situation. Or as I also suggested, use a real 110 V pump, as most radiant zones need and use, in conjunction with an inverter and battery to rid yourself of future problems with these tiny, low head, low flow pumps. 

Right, just like your computer fans and the like. But these too wear out over time from friction and can slow or stop with the build up of dust and dirt. First they become noisy and then eventually fail from wobbling around unbalanced, and eventually overheating. 
 Now add a potentially dirty hot fluid to the mix. Adding the more powerful head as you mentioned only helps the impeller to overcome this friction as you would expect. Of course you can't see the impeller in operation in an enclosed compartment so ruling out friction becomes more difficult, but the shorting and burning you witnessed should verify this. Adding a small amount of heat proof or waterproof grease as I mentioned may help reduce friction.

Thomas, where do you live? If you are trying to get refrigeration from renewables, and you live in a cold climate part of the year, then an air to air exchanger may work for you. Using PV, battery and inverter the rest of the year may work cheaper and easier. You can also add extra insulation to your refrigerator, if possible, or build your own. 

Thomas, no bearings, no brushes, so how do they spin? I think heat and friction may have a little to do with their failure as you already witnessed. Crack one open and check out the surface wear between the internal parts. Check for wear along the bottom edge and on the internal surface on the part that rotates. Or, if there is a friction reducing material, check for wear and tear or if it's missing altogether. If you grease it up and can put it back together you may get more life out of it.
 Best bet is to change over to a real, ready available pump and use PV to run it if that is your set up or goal.

William, another suggestion is, when you fill the system, add the water real slow in order to make sure each panel completely fills and purges....

William, sounds like the problem is with the panels being at an angle. Basically as you circulate the fluid, it only goes through one side of the collector trapping air in the rest of the tubes. This may be a result of how you piped the panels.
 Usually if you have two panels laying flat, connected together in parallel, the inlet would be let's say at the bottom left and the outlet at the top right.
  Since you have them mounted at an angle ( /  / ) you may have to do a series/parallel arrangement. Pipe the inlet to the same side of each panel, on the bottom of the panel, nearest the roof ( __ /___ / ). Then connect each outlet together on the opposite side of each panel that is above the roof returning back to your tank. Cap the other 4 ends.(2 at the top of the panel nearest the roof and 2 on the bottom of the panel up in the air) This will give you the cross flow that is needed. 
It's not to a big deal if you have them in series as long as you feed the bottom of the second panel from the top of the first panel that has it's inlet on the opposite side on the bottom.   
 Let me know if you get it. I'll do a better drawing for you if you don't.

William, the can vent on the air scoop should be all you need. Do not install the others on the panels. Put the panels back in parallel if you can. Now, how do you fill your system? Do you have two drain valves with a check valve or ball valve in between them? If so, and you already have glycol in the system and do not want to drain completely, use your pump to pump extra water or glycol from a bucket into one of the valves filling the system. Attach a washing machine hose or short hose to the other valve at the end of the loop, and have this hose discharging into the same bucket you are pumping out of. Run the pump for several minute until all the air is purged out and the glycol flows air free. Then shut off the discharge valve and continue pumping until you reach your desired pressure, then close the inlet valve.
 

If you do the math:
 At 1m/s, an area of 6ft x 2ft will supply 1750 gal/min or 40 ft^3/s.

Narrowing this down to a 3 ft x 2 ft area still pushing 1750 gal/min will give you 2m/s.

Drop the area down to 2ft x 2ft gives 3m/s.

Then to the minimum area needed for this unit, around 16 inches square, will give you the 4 m/s needed to reach the desired 8 amp output.

Matthew, when you say 12' sides, do you mean you only went 12 feet from the unit? Did you just use some 12 foot pieces of lumber or something? At what angle did you have the V or how far apart were the two ends, can you estimate the velocity of the flow and how deep the water is entering the V? If you can get the unit up to half power with just this small setup it shouldn't take much more to bring it to full power.
  I assumed you would start about 100 feet up stream, so if you are getting half power with just 12 feet that's pretty good. Just use the math I gave you earlier.
 Another idea is to build a diversion into a small pool/reservoir upstream. Then you can filter the debris from the stream going into the reservoir. Use this reservoir as the feed into some PVC pipe or your channel.