Ok next mod is up! I decided I didn't like to heat up 6 gallons of water just to do a few dishes, or take a shower. It takes 30 minutes to fully heat all that water, and is just a waste of propane. If you always want access to hot water, you need to keep the hot water heater turned on, more waste of propane. Plus, the thing sounds like a small jet engine when it is heating. So I removed it, and installed a tankless on-demand Girard 2GWHAM water heater.
The cool thing about the Girard is that it fits in the existing hole in the side of the trailer. It is actually a bit smaller than the Atwood/Dometic that was in there. But no problem, Girard provides a door that fits the exact opening needed for the Atwood/Dometic. That is awesome! Those guys thought about this.
The install isn't that hard, just takes some time. Couple key points for the install, if you're going to do this yourself. 1) Use butyl tape on the outside to make it water proof. 2) Since the Girard is not as wide as the old heater, you need to install a 2x4 (or similar size) vertically next to the Girard, to provide it with extra support so it doesn't move around. 3) The Girard comes with a nice simple control panel to set the desired output water temperature. it needs 2 wires. Good news! The Atwood uses four wires that run to the white panel with the two switches in your HQ switch panel. I just used two of those wires and installed the Girard control panel. See pictures. 4) The Girard has a valve on the cold water inlet so you can reduce the volume going in. I highly recommend setting that valve so that it lets in as little volume as possible, which is 0.8 GPM. That is plenty of flow to take a good shower. Anything more flow is a waste IMHO. 5) You use these a bit differently than the Atwood/Dometic, where you mix in cold water to get the desired shower temperature. With the Girard, I set the temperature I want for my shower (109F) on the control panel, and turn the shower valve to full hot. Reason being, if you mix in cold water, the shower valve will reduce the hot water flow at the same time. If the flow drops below 0.7 GPM the Girard turns off as a protection mechanism. If that happens you're now enjoying a nice cold shower
First, drawbacks of the Girard (or any on demand). 1) You can't get a slow trickle of hot water. The minimum flow is about 0.8 GPM to get the thing to kick in. 2) You can't plumb in a hot water re-circulation system anymore (as John has done), see point #1.
Now the benefits! 1) You always have hot water available! Yes, that was the point
2) The thing is super quiet, you don't hear it at all. The water pump makes way more noise. 3) You just saved 51 lbs of weight (6 Gallons of water). 4) I was shocked how dirty the water was that came out of my old hot water heater. When you drain it with the outside drain plug, not all water comes out (plug sits too high). When I had the heater out and held it on its side, this dark and murky water came out. Bah. 5) No more water bypass needed in front of the heater to winterize. Just blow it out or put antifreeze in the lines as usual. 6) It has an anti-freeze protection. It will briefly heat the water in the pipes inside the water heater if it senses a temperature below 38F. 7) I discovered the Curt emergency brake backup battery box next to the Atwood in a place that is not really accessible on my HQ15. But that story is for another post.
Ok, here are the pictures!
