Works great but read the directions and know tankless vs. tank
I haven't seen any in depth reviews regarding this heater anywhere. actually, i don't see many reviews for rv tankless hot water heaters at all, but the ones i do, it would appear there is more operator error than product issues. being that i have a tankless hot water heater in my house, i already understand the ins and out of water flow and temperature fluctuation and wasn't worried about that "problem". the heater comes with no mounting flange or door. you have to purchase that separately. i highly recommend you order them separately else i have no idea how you would safely secure it and protect it in an rv mount. other than that, it's a pretty straight forward installation. all the connections are on the back of the heater: cold water in, hot water out, propane in, and voltage regulator hookup for adjusting the heat (more on that later). i did the install myself. on a scale of 1 to 10 for diy skills, i'm about a 9.5 and nothing in the manual seemed new or perplexing in anyway. this job took quite a few little extras to get to fit right due to the tight space to work in, rewire the electric, and replumb the pex pipes. you could use sharkbites or other clamping connectors for the water pipes, but if you are going to permanently mount it and be bouncing the road in an rv, i recommend pex clamps for safety. i disconnected and removed the old water heater which is as straight forward as it sounds. the girard is sized to fit the same hole as a surburban or atwood. but mine did not fit. but not because the girard was made incorrectly, it was that the skin of my rv around the hole was not cut correctly at the factory. a quick trim with a hacksaw and it slid right in. you do not need a water bypass setup for this heater like you do when you winterize a normal 6/10 gallon rv heater. i cut away the bypass manifold from the original rv piping and left just a cold water and hot water pipe. used my pex crimping tool to put on 1/2" female swivel connectors. wrapped in teflon tape and hand tightened as per the instructions. for the propane, they recommend you have 11" wc or else it just ain't going to work right. modern rvs have a propane system regulator that will supply this with no problem assuming its working correctly. i hooked mine up and had no issues. measuring that kind of stuff is not something you get into unless you know what you are doing. electric is a simple 12v in and a ground. with mine, i hooked my 12v up to the existing 12v that comes from the hot water on/off switch in my bathroom. the girard does have its own on/off switch on the outside face. with this setup, i can leave it on at all times and then control it from my heater switch in the bathroom just like my old water heater. as for the voltage regulator temperature dial, this controls how much "flame" the heater will put out. this is separately mounting dial aside from the on/off switch. it is provided with the heater. you set it to high when it's cold out since the city or tank water will be colder. tankless heaters can only only do so much to raise the inlet water temperature on demand. this one is rated for a maximum 70 degree rise. so if your inlet water is 40 degrees, you can theoretically only reach 110 degrees. if it's hot out, you can then dial back the heater so it doesn't need to use as much propane and you can better control at the faucet the water temperature. the manual recommends setting it in the middle and then adjusting it through trial and error to find the sweet spot. the temperature dial uses a ground and a signal wire back to the heater. my old heater had a "reset" light mounted in the bathroom next to the on/on switch. i was able to use that wire to send the voltage regulator signal back to the heater to control the temperature. that allowed me to mount the voltage regulator dial in my bathroom next to the on/off switch. once it was all connected and i double checked my fittings, i connected city water from my garden hose on a 41 degree day. opened the kitchen sink faucet and listened to the heater fire. within about 15 seconds, the water was hot, but not anything great. i then turned the temperature dial to max, as the instructions suggested, and i immediately got hot water to the point it was almost uncomfortable to touch. i then repeated this in the shower by opening the hot water faucet only full open. hot water right away, but probably not hot enough to take a good s shower. now this where most people go wrong and want to send their heater back!!!!!!!!! they think that the temp is set to max and this is the hottest the water will ever get. all you need to do is turn down the hot water a little bit, this will reduce the flow into the heater, and with the water going slower through the heater, it will get hotter. also if the water gets too hot, the natural though is to add cold water. actually, it will to a point but if you add too much cold water, it can reduce the overall flow enough into the rv that the water heater hits the 130 degree overheat and cuts off. that's when you get the infamous "hot,cold,hot,cold,hot,cold......" spikes that you see a lot of reviewers complain about. but once you understand how this all works, its a piece of cake to regulate the temperature. listen, it's an rv, not a room at the marriott marquis. i have no problem making this compromise to be able to take long hot shower on a weekend getaway in a house i can tow behind my truck ;) anyway, i dialed back the hot water flow a bit and it got hot enough to start steaming up the shower and i still had plenty of water volume. probably 1.5 to 2 gpm. i would easily assume that once the weather turns warm i can dial down the temperature dial to compensate for higher inlet temperature from my hookup. i also disconnected from city water and ran it from my onboard tank pump. my onboard pump was never that great to begin with, but it does have enough pressure and volume to trigger the water heater minimum flow to fire. i was able to run the shower with hot water just from my pump for 5 minutes of continuous testing. but i will say, if you do a lot of dry camping, a tankless is not for you. you will go through more water and need to dump more often simply because of the nature of the beast and because you will no doubt be taking longer showers. i don't mind that tradeoff in any way since i always go to full hookup campgrounds. overall, i am pleased with my purchase although i think it's total bs you have to purchase the flange and door separately. i do realize that one day of testing is not a full on hands on review, but from what i've seen so far, i don't have any reservations of using it a lot this spring, summer, and fall. if you do a lot of rving or a full timer, i think this is a "must have". you will need to experiment and learn how to dial it in, but once you do, i think its a great addition. i hope to come back to update this review after a season of usage.