Hello Mr. Wells, Thank you for the kind compliments. The problem with going straight up with the concentric pipe before the 94° elbow is that condensate drips back into the heater and corrodes the internal components and is the simple reason why this should not be done. After the elbow, the stainless steel pipe slopes at as slight down-angle and condensate drips outside at the exhaust exit point. When you explore your local and/or state and Federal "code" you will find that venting under the eave is almost always prohibited because of the potential of entry of carbon monoxide into the home through the eave vents. The difference between ground water temperature and the exiting hot water temperature is called "rise" and this number is usually a fact of geography. Northern users and those with very deep wells have much colder water and need higher levels of rise than Southern users due to the differences in these ground water temperatures. The larger the rise factor, the lower the GPM (gallons per minute) any tankless heater will produce. If you have very low ground water temperatures, it is best to purchase a heater with a higher GPM rating to overcome this temperature difference. There are some ways to preheat incoming water. For example, with the incoming water supply passing through coils wrapped around the exterior of the sanitary drain pipes or passing along a heating duct etc. There are videos and users on RU-vid who show their "MacGyver" type devices to do this preheating of the water supply. Sincere thanks for your interest in our products. Jim

Hello, These do not work in any position other than upright for a number of reasons. Primarily, the heater must be "upright" as by design, the fire is "under" the heat exchanger that has the water running through it. This heat from the fire must rise through the heat exchanger to heat this water that is inside the heat exchanger. As "heat rises" (it does not go sideways) your idea is impossible. Thank you for your interest. Regards

Simply because there are codes regarding room size versus BTU on gas-fired devices. Tankless heaters often have very high BTU ratings. To meet code, our smallest "room air combustion camping and cabin" model must be in a room the size of a two car garage with no closable doors. in a super-tight dwelling, a furnace and any other gas-fired device should never fight each other for combustion air as the more powerful one can reverse-flow the exhaust causing freeze damage and/or the risk of carbon monoxide poisoning. it has nothing to do with starving your home of air, therefore, it is not utterly ridiculous.

Hi, With concentric pipe, the answer is always no. There are redundant saftey devices built-in that understand imbalance in most units. All brands must have intake and exhaust configurations that are within the manufacturer's specifications. Best regards, Jim

Hello, The reason you cannot vent vertically is that the exhaust must run slightly downhill to drain condensate that accumulates inside the pipes; The Concentric pipe vented EZtankless heaters cannot be vented vertically. This is explained on our website and in other videos that are specific for each product. Thank you for your interest.

Hi Steve, The reasons they mount them on the outside of the food trailers usually relate to rules of gas-fired appliances. Typically the "code" states that you need 30 cubic feet of room (with no closable doors) for each 1,000 BTU of these devices. If you have a code inspection, an indoor mounted one will likely fail inspection for that reason. If you were to buy a "direct vent" model you could mount it inside as they do not use "room air" for combustion as the intake air supply is drawn-in from outside through the external eccentric pipe. thank you for watching. Jim

Hi, No, this direct vent concentric exhaust will not work as the 101 is not direct vent design. I see you have additional questions, please contact our company directly. You can find our contact information on our website www.EZtankless.com Regards, Jim

Hello, It depends upon the type of tankless heater. Your concept is very energy conservative, and indeed people do this. With any "smart" tankless heater, the desired water temperature is entered into the control panel. There are intake and exit water temperature sensors that the computer uses to regulate the fire and air in the firebox. This process regulates the exit temperature of the water to make it consistent. If the water coming into the heater is almost as hot as the desired temperature setting on the control board, the heater will either not run or it will run in a very relaxed mode. (If very hot water was introduced into the heater, it is conceivable that it may be possible to damage small components on the water inlet side of the heater as they are not designed for high temperature water. And it makes no sense to introduce water into a heater that is hotter than the desired exit temperature. If this were the case, there would be no need to have a heater. But yes, you have valid points. Perhaps with your idea, it would be wise to have a way to use your solar-heated water directly, or if need be, set-up the system so that you could open a valve to divert the water through the heater to raise the temperature as desired.) The difference between intake temperature and exit temperature of the water is called "rise" - The less rise, the higher the GPM (gallons per minute) that the heater can produce. thank you for watching our videos.

+Christopher Ricci Hello Christopher, No, it will not supply enough hot water. You must match the heater GPM specifications to your pressure washer. In this video, we are using a smaller pressure washer. Of course, "hot" water is relative to your ground water temperature and how hot you want your pressure washer temperature. Remember, all tankless heaters are rated by GPM and "rise" combinations. the actual GPM of any tankless heater depends upon these two factors. incoming water temperature and your desired exit temperature. (the difference between these two water temperatures is called "rise) All tankless water heaters lose GPMs when you raise the "rise" factor. For example; People in Florida who have almost 70° ground water temperature get much higher GPM and/or hotter water than those who live in Minnesota and have a 40° ground water temperature as there is 30 degrees of incoming water temperature difference right there. Regardless of the brand, tankless heaters GPM and rise statistics are related to several factors, incoming ground water temperature being one of the most important.

Thanks for the reply im in northwest Ohio so seems like it would take quite awhile to gain that desired gpm needed which is around 6 I will be using it to clean shingles and portable hot water is hard to set up but I am still very impressed if you have any recommendations as to what might work let me know if not thanks for the advice anyways

+Christopher Ricci We did... ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-TiybpozesSM.html

Jon Callaghan Hello Jon, No, it is not normal for a gas smell and in fact this could be potentially dangerous. There are redundant safety features on all brands and models of heaters to prevent gas build-up without ignition. If you smell gas, you should be looking very closely most likely at your gas connections to your heater. A leak in your supply line is very dangerous as it is not within any heater's safety features' ability to control. If not the connections, you could perhaps have some type of leak related to the gas solenoid valves but this is extremely rare.