Heating using the hot water tank.

[MtnDon]

Sorry to hear about the need for your wife's surgery. That can make one lose focus on other stuff.


You could start with a radiator hooked up above the water heater tank and a fan or two. Visualize a pipe tee'd into the hot outlet line and leading to the heater core / radiator. Then a line from the other end of the radiator returning to the cold inlet line at the water heater. See how much heat you get oiut of that. If it seems to not be hot enough a recirculation pump might make it work better. But maybe it would work w/o the extra pump.

I found that I needed to bleed the air out of that loop before it would begin to flow from convection. I used a tee fitting with a valve I could open slightly to bleed the air out. The pressure pump would sense the drop in pressure and turn on, forcing the water through the line to the bleed valve. After closing the bleeder the water would continue to flow through the loop by convection. I think there are valves with a bleeder cap/screw. I just used a shut off I had kicking around.

Hope that makes some sense.

[lrrowe]

Thanks for your comments.

Yes it does make sense. Do you have to do it once or frequently, such as when you heat things up again?

[MtnDon]

I only had to burp the system once to get it going. Of course if I drained the system it would need to be repeated.


It was a different application. The problem I had was the cold exterior temperature; zero and lower. Coupled with 20# cylniders the tank could not supply the volume of propane required for the heater burner. The burner would flame out. We do not plan on camping in temperatures that low with this trailer.

[Shadow Catcher]

I also am sorry to hear of your wife's surgery, she and you will have something to look forward to.

I managed to pick up the expanded metal yesterday and today has been productive, holes cut/drilled for the goesinta and the goesouta. Cut the expanded metal with a 4 1/2 angle grinder and wafer wheel, glued the brackets (don't know what else to call them). The last set for the fan and its mesh guard are setting now (pictures are backwards actually, as it is all in pieces). There is still a bunch of finishing and insulating but it is more or less complete.

[lrrowe]

Thanks for the thoughts.

I gather from your middle photo that you are separating the radiator and the fan by a few inches.

What size radiator are you using?

[lrrowe]

I only had to burp the system once to get it going. Of course if I drained the system it would need to be repeated.


It was a different application. The problem I had was the cold exterior temperature; zero and lower. Coupled with 20# cylniders the tank could not supply the volume of propane required for the heater burner. The burner would flame out. We do not plan on camping in temperatures that low with this trailer.

Nor do I want to be out there in that cold. But lets say you were. Is there a way to insulate the 20#'r? It should not go inside the trailer that is for sure. Would it help to wrap it in insulation wraps? I doubt it as what heat is there to hold in? Maybe it would slow down the cooling rate of the propane from hopefully warmer temps earlier in that day.

[MtnDon]

Bob, IMO there is no easy / safe way to keep the propane cylinders warm when the temperatures get very low. The nature of propane changing from its liquid state to a gaseous state works against you. That process absorbs heat or another way to look at it makes the cylinder colder.... frost forms on a 1 lb cylinder as it is used, as an example. There are 120 volt AC blankets made for keeping a cylinder warm (not cheap). That needs grid power or a generator or a very healthy sized battery bank.

The larger the tank the better the cold weather performance. I have a link to some good info I complied. I think I posted it here once; I can re-post it if you want.

[lrrowe]

Bob, IMO there is no easy / safe way to keep the propane cylinders warm when the temperatures get very low. The nature of propane changing from its liquid state to a gaseous state works against you. That process absorbs heat or another way to look at it makes the cylinder colder.... frost forms on a 1 lb cylinder as it is used, as an example. There are 120 volt AC blankets made for keeping a cylinder warm (not cheap). That needs grid power or a generator or a very healthy sized battery bank.

The larger the tank the better the cold weather performance. I have a link to some good info I complied. I think I posted it here once; I can re-post it if you want.

Thanks, but that is ok for now. As you and I said, we will probably not be out there in that temperature anyway.

[Shadow Catcher]

The radiator/heater core is 1.5" X 7" X 7.5" actual finned area.

[lrrowe]

Thanks.
It looked larger then that.

[MtnDon]

If that's the fin size, that is 20% more area than my Hayden 401. Just FYI.


Makes it easier fitting a single fan.

[Shadow Catcher]

The 200mm fan has just a bit of overlap.

[lrrowe]

I think I will go with this one.

http://www.amazon.com/gp/aw/d/B000V6FKG ... CFL9LU89NR

It is large, 3 good speeds, good (low) amperage, but not as quiet as some of the direct from China ones T 19db.

Cindy and I believe Gonefishin have it and like it. It costs more then two of the smaller ones, but not too bad.

[Shadow Catcher]

All the bits and pieces are painted and coated, core sanitized and ready to assemble. I had thought of painting the core but the space between fins is so small it would be difficult to keep it from plugging. In thinking of how to block air flow from the fan from not going through the core I played around with various ideas and decided to just start with using some foam insulation, probably pipe. I also need to fill in some gaps around the core and that will work for that as well.
I have also been thinking of how to be able to attach hoses and be able to disconnect... and a double shutoff quick disconnect for both hoses is perhaps the best answer. When disconnecting both sides, pipe and hose are closed when not connected and I am looking at what is available.

[Shadow Catcher]

I finished the core portion today, used closed cell pipe insulation to block up gaps around the fan and core. It would look nicer if I were not relying on some very basic hand tools. Waiting on pump and need to suss out hose and quick disconnects.
In the house the fan is virtually silent and there is not a great deal of airflow or does not feel like it. In CR I don't know that there needs to be much, heat will tend to rise and stratify. To prevent this from happening with the 120AC heater we run the 80MM case fan(s) which have enough stand off so that air can get in above them and be directed down.
Finished product!