I've had one for almost four years. No issues. A few seconds of extra lag for hot water. The model # is not the same, but I purchased the largest they had available at the time. You do need a water softener if you have hard water. Hardness scale will destroy a tankless in a fairly short time. I would buy one again. The endless hot water is wonderful. I seriously doubt you make any "green" difference compared to a standard tank design. A 7-8 year payback is not a payback at all, particularly if you did not take inflation into account. That would place your payback at more like 20 years, about the time to replace the unit anyway.

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.

Rinnai is the largest gas appliance manufacturer in the world. They are based out of Japan, but have a North American HQ in Peachtree City, GA. You might want to check out www.foreverhotwater.com. This is Rinnai's consumer site.
If you can get your Rinnai installed as close to an outside wall as possible to avoid the cost of the venting as well as close to your master bath as possible. While the Rinnai tankless gas water heater produces hot water instananeously, you still will experience the cold water in your piping between the unit and the fixture. This issue can be solved with a circulating pump produced by either Metlund or Laing that are specifically designed to be used with tankless gas heaters.

Bottom line, Rinnai gas tankless water heaters are one of the "hottest" products in the plumbing arena. These units save a tremendous amount of gas, do not emit carbon emmissions and when sized, installed and placed properly supply endless hot water on demand.

do not emit carbon emmissions and when sized,

No matter how it's sized, if it's running off natural gas or propane it's going to emit CO2.

Rinnnai is a respected brand. You should expect to save about 35% on water heating costs over even a well insulated tank gas water heater. Even so, it's usually not a large number in actual savings. $3200 could have a better payback in $ and environmental impact somewhere else -- such as insulation.

The cost sounds high, although I don't know about currency, VAT and all that.

You need to be able to keep the flue short in order to make the installation reasonable. With a short flue, the installation labor shouldn't be much more than a standard gas heater. The cost of the unit is, however, more. My unit (Rheem) cost me close to about $1000 in materials including the flue kit.

I look forward to a time when the labor to install a tankless is less than a tank. The truth is they are smaller, lighter and much easier to work with than a tank. I also look forward to a time when they vent with PVC instead of stainless steel.

Takagi does have a PVC vented 90%+
Low temp only (domestic not heating)

Cost to plumber is like $2,600.00.

My friend from Takagi told me they have only sold 4 in the US since 2006, I can understand why

I have a Rinnai natural gas w/h. The unit was $1,200 and I paid $600 to have it installed. Mine is located outside though, so it just self-vents. I understand that venting it from inside/through the roof can be expensive. I love the control we have over the water temperature. DH likes 120 degree baths, my kids get a 105 degree bath, and I can sanitize sheets in the washing machine at 140 degrees. We put ours closest to the laundry room and kitchen. It does take a bit longer for hot water to reach the master bath.

I have no direct experience with them in the U.S., but I lived in Japan for 10 years and Rinnai is everywhere. Very good stuff. We had a small one that supplied the kitchen sink (mounted on the wall outside) and a slightly larger one that supplied the bath/shower and vanity sink (also mounted outside). They worked perfectly.

- Don