The reason we have 2 tankless heaters is so both of them are close to the point of use, which equals less wait time. I also drew our house plans to make sure my hot water use areas were "clustered" because of this. Due to the piping in our double wide, we have to wait up to 5 minutes for hot water from a tank heater. Ridiculous. I have played around with my parents' stuff and have never waited more than 10 or 12 seconds for hot water because their heaters are also near the point of use. Their and our tankless heaters are Rinnai, btw. The only instant hot water I have ever experienced was in a really nice hotel... ;-) I don't know how big our current tank is, but we often run out of hot water for our family of 4. I'm looking forward to never dealing with that again!! Vonda PS Hello to a fellow Arkansan. Might not be the greatest state in the Union, but it's home. :-)

keadog Based on your options, GT should be in the trade space. It sounds like you are in a rural area. We built in a rural area in 2007 and have a Gt system - propane was our only other option (we only use that for cooking and tankless hot water). Here are some lessons learned from my expereience: 1) Make sure you factor in the cost to run the electrical service to your home AND make sure you get enough amperage. The GT heat pumps need quite a bit of current on start up - my 5 ton heat pump requires a 70 amp circuit and my 3 ton heat pumps require 30 amps. Once the heat pumps start they draw less current - but you still need to factor the start up load into the overall needs for the house. The added cost for additional amperage is relatievly cheap when they install - but very expensive to add later. Based on your house size I would reocmmend a 400 amp service if you go with GT. 2) If you do chose GT, I strongly recommend a propane auxilliary heater instead of the electical heat packs. Have the system wired so that a small backup generator can power the thermostats, the HVAC fan, and the propane heater ingition. That way, when the power goes out you can still have heat. An alternative is to install a larger backup generator that can drive your GT heat pump and loop but that might not be cost effective. Either way - make sure you factor in a backup heating system into your plans. 3) Make sure that the company who is doing the GT system has been in the business for many years AND is available to provide service. These systems have to be designed properly and must be tailored to your specific site and house design. They are expensive and you need to have it done right AND have a reliable company that can service it when needed. If you can't find a highly rated local company to install and maintain the system then I would not recommend GT. 4) Make sure you factor in the building envelope: windows, doors, sealing and insulation into the overall HVAC design. If the envelope isn't tightly sealed and insulated well you won't be happy with a GT system. 5) Do your own research on the Heat pump manufacturers - use this site to ask the experts on the proposed equipment. Make sure it is a quality product. 6) Ask the HVAC contractor what type of monitoring system they provide so that you know that the system is working as efficiently as designed. Mine had nothing and I had to add indicators such as pressure and temperature guages over time. Goodluck with the build.

There are minerals and traces of other chemicals in your water. When the water is heated, they get together with any exposed metal in your tank and form precipitates. These are solid paricles which fall to the bottom of the heater, where the burner is. As they collect, they form a layer across the bottom. This layer becomes thicker over the years. By the time you start to notice hot water shortages, this layer is probably a good five to ten inches thick. The higher you turn the temperature, the faster the precipitate forms. The anode rod is a sacrificial piece of metal which dissolves more readily than the steel tank. It lasts around three years. Your hw tank is lined with glass. But the seam on the side of the tank is welded after the tank is lined, and so the glass melts. So, to make the heater last a long time, drain it once in a while, change the anode rod once in a while, and keep the temperature low. There are only three manufacturers of residential water heaters in the US: Rheem, State, and A.O.Smith. All others have contracts with these manufacturers. Read the fine print on the label on the water heater. They have all been in business for a long time. If one is worse than another, it won't stay that way for long, because it will lose business. State has a patent on a special fill tube that circulates the water and keeps precipitate in suspension, but big bucks. State has sued other manufacturers for infringement and won. Otherwise, as far as I know, they are all pretty much the same.

dan i have two rinnai LP gas units that are ganged together in series. the two digital controllers are linked and when i set the control on one unit, the other automatically updates. the only negative i have with the rinnai's is that the controller can only adjust temps in increments of 5 degrees - i wish it was in 1 degree increments. for us, it was more efficient to have two small units installed rather than 1 large one. this was done for efficiency - most of the time we only need one unit running but there are cases where the second will kick in. gas tankless is great and the rinnai's look to be well built. 3200 sounds very high to me. I don't know the exact dollar number for ours , but the 2 rinnai's we had cost us an additional 1200 dollars over what a hot water tank would have cost (we just paid for the upgrade). my guess is that a hot water tank installed would run around 800 dollars max - so I am having a hard time seeing where the 3200 price tag came from. is there is a lot of plumbing and venting work required to install your unit? i do know that the ducts for the tankless units are very expensive, so if you have a long run for the vent - that might be where the extra cost is.