Originally Posted by VTstang
At this point in the build I need to take a slight detour and give some back story. My house was built in 2011 and the builder went with a tankless natural gas water heater that is mounted on the outside of the house. I assume this is cheaper to install because it does not require running a chimney. And while these may work well in Florida, they are less effective in Virginia....
Wow. My sympathies. That is a real PITA scenario you have there.
I'm surprised you are in Richmond and have to deal with that kind of weather, though Richmond is known to get every kind of frozen precip at one time or another, it's certainly not common AFAIK
(or is it)? I lived in NOVA over 20 years. One of many things I don't miss about that area is the weather!
I am really surprised they installed the H2O heater on the outside of your home. That is really daft IMHO. My wife is from Europe and they've been using tankless water heaters for decades. Her parents' is installed in a kitchen cabinet. There is no need to mount them externally. Sounds to me as if the home builder and/or contractor was inexperienced.
I hate to say this, but it seems to me the best solution for your problem would be to relocate the water heater indoors. Even in your garage would be better. Obviously you don't want it in your HT room, though that might be the easiest/cheapest means of doing so. Otherwise, you're looking at a significant tear down to relocate the pipes. Unless... they can be accessed further upstream from elsewhere in your home. Have you traced your water lines? If you can locate the line that sources to your H2O heater, and the source hot water line from the H2O heater, you'll get a better idea of your options to move the darn thing.
... upon opening the metal box, all the insulation was frozen with ice. So I called a plumber and they could not find any breaks in the part of the exposed pipe. This meant, even though I did everything I could to avoid the problem, that I would need to tear into the front wall of the theater. That's two layers of Linacoustic, a sheet of plastic, two layers of wall, one of which is wood, and green glue.
If look back at my build you'll see there was a section of pipes that we had to frame around on the front wall (i.e. create a box around) and the plumbers thought it would be best to try and open that to get a look at what was going on. It took us about an hour to get the right side end cap off the box which only provided us with about an 8" square window. We could not see anything obvious, but the plumber commented that it was freezing in the wall and that's likely where the pipe was frozen. He said to wait for it to thaw and then we could determine the source of the leak. I noticed that not only was the area inside the wall cold, it seemed to have a draft, which I cannot explain (i.e. blowing cold air in the wall). Even with a portion of the wall open to the theater room which I had set to 76 degrees, it took another ~30+ hours before it thawed. Here is where it gets crazy. Once it thawed, there was not sound of a leak, or any other indication of a leak. Even on the outside at the metal box where the insulation was frozen and there was a giant icicle, it was completely dry. I have been monitoring it now for like 2 weeks, and still no indication of a leak. I cannot explain it, but I guess I'll take it.
My thoughts FWIW.... I can think of 2 possible causes. The most likely would be condensation. The other is if you have a void that is created when one part of a joint expands or contracts due to temperature changes/differences.
In the first case, temperature differences cause condensation. I've seen this with HVAC supply vents where the insulation was not properly secured to the flex duct near a transition from attic to finished space. When the A/C was run, condensation formed on the finished space side. When the heat was run, condensation formed on the attic side.
In the second scenario, it's possible for leaks to occur in a similar fashion, primarily around a seal. Could also be a bad seal (though that can be tested if it's possible to put the system under a pressure test).
... I am getting tired of this water heater issue, but there is no way to move it and even if I were to frame it in and better protect it from the elements, I still have an exhaust issue for the natural gas combustion byproduct and the draft in the wall.
There's always a way. It's a matter of cost, effort, and time. First I'd suggest due diligence to trace your pipes/flow in your home as best you can. That will allow you to determine the actual effort required. Don't trust a pro to tell you it can't be done (if that's the case). Just because they can't envision accomplishing a task doesn't mean it can't be done. Find a pro who thinks outside the box.
A few more thoughts....
1. Does your homeowner insurance include water damage? If yes, you should investigate that path.
2. Have you contacted the home builder? I understand your home is most likely outside the warranty period for the water heater (from the builder), but (especially if you are the original owner) some builders don't want their reputation tarnished and will endeavour to solve your problem as a gesture of good will.
3. Consider suing your home builder for your costs to-date and the cost of rectifying the problem (note: if your insurance would cover this issue, you may be required to go through them first - depends on your insurance policy). In Virginia, you may also sue for loss-of-use damages. If you can prove negligence on the part of the home builder, it would substantially increase the damages award. You might consider this approach in conjunction with #2
above. Nothing gets home builders' attention like a lawsuit and negative press coverage when they are building nearby. Just sayin'.
4. If you decided to sue, you'd need/want a forensic examination of your water heater. It could be a manufacturing defect.