After ours was installed I stumbled across a company that makes an all in one unit called Eternal Hybrid (link below). You may want to contact them and see about getting the energy efficiency specs to go that route. I think Navien also makes an all in one system now too. I would think either company would be able to give you more accurate energy specs and better answer your question. The other thing to keep in mind is that without the loop (& pump), you are in effect wasting gallons of water waiting for the hot to kick in--think showers, sinks, etc. How much does the water wastage cost in terms of both water & sewer bills + the unnecessary waste of a resource? In addition to washing machines not pulling enough water through at a time to trigger the heater and then remain on long enough to actually get the water down the line to the machine, some dishwashers are having problems too. Here is a link that might be useful: Eternal Hybrid Hot Water Heater Site

Actually, after futher review of what happened, it was maintenance that possibly (kinda sorta) contributed to the water leak. The day before the leak, I was doing maintenance on my washer and dryer. I was cleaning the lint from the dryer vent. Also, I was cleaning out the washer tub. I think I must have moved the utility sink a bit and caused the pex supply line that goes to the sink to move a bit, maybe causing it to loosen and then the heat and water pressure built up and popped the hot water supply line out of the bottom of the faucet connection. Either that or the rubber o-ring just gave out from the heat and water pressure. So, I changed both lines to the steel braided type that I have on my washing machine supply lines. This should hopefully prevent any further issues. And, yes, live wire oak, although you seem to assume I do not do maintenance around my house, I do indeed regularly perform maintenance around my house, to include: flushing the water heater twice a year, cleaning the dryer vent, cleaning the gutters, cleaning and servicing my water softener, changing the carbon and sediment filters for my well water, prepping and staining my deck, lawn/landscaping maintenace, maintenance of lawn equipment (riding mower, trimmer, blower), maintaining and cleaning of pellet stove, maintenance on two automobiles....etc...etc...etc... I guess I have to add inspecting supply lines to that list. And, yes, brickeye, I could not agree with you more. Maintenance is less work than paranoia......that is why I try to do as much as I can around my house to avoid the catastrophes..... thanks. mm

Marie26, I don't believe turning up the thermostat will increase the speed at which your water heats. Such appliances normally turn on at full power during start up, as it gives you hot water faster, and then reduce power when they reach the required setting. Anyway, once it does heat up your water may be too hot and need mixing with cold to get the ideal temperature. Unfortunatly, the hotter water becomes the less readily energy from the element transfers in to it, thus the efficiency goes down with increasing temperature. It's preferable to heat a large volume of water to the right temperature than try to super-heat a little water and mix it with cold. You may find that you're a good distance from the water heater and pipe insulation improves the speed at which hot water reaches you. I have a normal tank heater, so the time it takes for hot water to reach me is mostly pushing standing cold water out the pipes and the heat lost by the pipes themselves. Thus your delay may not even be caused by the water heater. Insulation did improve the hot water in my house, and it has allowed me to turn the temperature down a bit now that I'm not passing it through a long metal pipe before using it.

I have a Triangle Tube Series 50 (45 gal.) in a 2,000 sf house with 2 bathrooms. My plumber said I should put in a smaller unit and I wanted a bigger one. We compromised on this unit, because he said a bigger one would consume a lot more energy. I take a 25 min shower with a 5 gpm shower head, and I get enough hot water from this unit, but it took some doing. The first thing I would suggest is to turn the temperature on the water heater all the way up. We have an L-shaped ranch with the water heater on one end of the house, and the master bath on the other (over an unheated crawl space). So we need to keep the water very hot to get enough hot water at the bathroom. The hotter the water is, the more cold water you'll mix in, and the longer your hot water will last. Despite this, I was still running out of hot water after about 15 min. As my shower valve doesn't have a volume control, I put a small valve on the shower arm which allowed me to slow down or shut off the water when I was soaping myself. This allowed the hot water to recover a bit before I finished my shower. The real breakthrough came last summer though, when I had a new boiler installed. The installer told me that the circulator pipes between my boiler and water heater were only 3/4", when they should be 1 1/4". He also set up the new boiler so that the water heater gets priority over heat to the house, and the boiler automatically heats up to 180 degrees whenever the unit calls for more hot water. Now I have plenty of hot water for a 25 min shower followed by a shave, even without turning the volume of hot water down during my shower. I think you should be able to get enough hot water out of this unit provided you use it to its full capacity. You may need to have someone do some work on your boiler though. One rule of thumb I live by, is to never let a contractor tell me how much water or hot water I need. Aside from this, do you have separate shower valves for your 2 shower heads, and are you satisfied with the water flow? Many newer shower valves limit the flow to 2.5 gpm or less. You can check your actual water flow with a 2.5 or 5 gal bucket and a stopwatch. If you're getting enough flow out of the shower arms, but not out of the shower heads, there are some places that sell shower heads with easily removable flow restrIctors.