Looking for a tankless water heater to fit your needs can seem overwhelming, but once you sit down and compare the models, different specs, and recommended uses, it can become a breeze. Using a model for something other than what its recommended for, can be dangerous, void your warranty, and simply not be compatible with your use.
You should never use a OUTDOOR unit INDOORS.
Let me explain a little more in summary about each model and its recommended use.
The Eccotemp L5 is a PORTABLE tankless water heater. Its made to be used outside, but not made to be left outside. When not in use it should be drained a stored inside. This unit is not weather resistant and being left in the elements could cause damage to the interior, including corrosion. This model is generally used for on the go applications such as camping, temporary outdoor showers, washing your dog, your car, etc. This model is not recommended for indoor or residential use.
The Eccotemp L7 would have the same recommended storage and application as the L5. However, it offers a newer design, and higher water flow and BTU rating to get you a little extra boost over the L5 capabilities.
The Eccotemp L10 is our smallest permanent installation unit. It features a stainless steel rain cap to protect it from rain water falling back into the unit. The L10 is a manual unit, and with its flow capacity it is recommended for a outdoor installation at a small cabin, or apartment. It does not have adequate flow capacity to run a whole household, but can be used for a single room plumbing.
The Eccotemp FVI12 which comes in a liquid propane or natural gas style, is our smallest indoor unit. It comes with a horizontal vent kit to safely vent the emissions out the home. This is recommended for smaller homes, and has the capacity to run 1-2 water outlets at a time.
The Eccotemp 40H (outdoor) / HI (Indoor) is our full home residential model. This comes in a indoor and outdoor model (Venting sold separately.) At 6.3 GPM, it has the power to provide your whole house with hot water on demand. Always ensure that you verify the gas type (LP or NG) on the unit to ensure it matches your gas type.