No hot water in freezing weather

[doorguy]

Here is a new problem. During freezing weather, my hot water lines freeze up and I get no output at bath sink, shower or kitchen sink. Cold water thru all interior outlets is fine . I am on the pump at this point. The water htr is located directly behind the right rear wheels. Since the compartment is enclosed in metal, I took the bottom access hatch off and stuffed some fiberglass insulation in there as much as I could thinking it would help. No go. I've looked behind the exterior shower faucet where there is a plethora of hot/cold water lines, but seems to me if that area was the problem, I wouldn't have cold water either. Any ideas?

[puttin]

doorguy,

Are you sure the winterizing valve is not on bypass? If it is- you will only have cold out of both faucets. My valve is behind the water heater inside the coach.

[Dwight]

Hot water lines usually freeze first. Uncover & open as many wall access panels to water pipes as you can to give air the chance to circulate. A hair dryer can help.

[lllkrob]

Dwight is correct, hot water lines always tend to freeze first. In addition to allowing as much air circulation as possible I would suggest getting some type of auxiliary heat into your wet bay. Either a small cube type electric heater or a drop light with a 100 watt bulb will work. The principle is to get heat to rise and circulate around your tanks and through your piping runs.

[DAN L]

Originally Posted by doorguy

Here is a new problem. During freezing weather, my hot water lines freeze up and I get no output at bath sink, shower or kitchen sink. Cold water thru all interior outlets is fine . I am on the pump at this point. The water htr is located directly behind the right rear wheels. Since the compartment is enclosed in metal, I took the bottom access hatch off and stuffed some fiberglass insulation in there as much as I could thinking it would help. No go. I've looked behind the exterior shower faucet where there is a plethora of hot/cold water lines, but seems to me if that area was the problem, I wouldn't have cold water either. Any ideas?

i installed 3 wired inside-outside temperature gauges from harbor freight in my water bays to monitor temps.
i should have used a wireless setup.
i use a 60w-100w trouble light in my aft water service compartment. the rest are ok without supplemental heat.
i found that my electric cord compartment was poorly sealed and used foaming sealant to fix that problem.

[Clay L]

I have heard that hot water lines freeze first and it didn't make sense based on the thermodynamics course I took in college.

So I took two identical cups, filled one with hot water and one with cold. Put them both in the freezer and the cold froze first.
I have done the experiment a number of times over the years and the cold water always freezes first.

[wackodacko]

Hi Doorguy, we had the same problem last week . We were already running a little electric heater (200w) in the valve control compartment (where you pull dump valves, connect water hoses, etc) HOwever, the hot water lines still froze.
apparently, the weak spot in our rig (2004 itasca horizon 40AD) was in the rear most compartment on the passenger side. There, you will see some white water pipes. We covered the pipes with the gray insulation thing you can buy at Lowes or Home Depot. Then we plugged a 100W bulb with exentsion cord into the 110v outlet on that side of our bus, and left it in that compartment. It held up well at 15 degrees last night - no freezing.
Make sure you crawl under your rig and peep under that last compartment (passenger side) ours was missing a panel so cold air was coming in. we had to make one out of metal. i guess the guy who replaced our water heater in the summer threw it away, or it fell off.

[Shadowcatche]

Pipe trace, Heat tape (110) Pipe Trace Freeze Protection Heating Cable and pipe insulation.

[1ciderdog]

Barry, We had the same problem when we were in Sierra Vista about a year ago. Record cold with single digit temps at night. First night hot froze and the next night both hot and cold froze. We were at an RV park with full hook ups and water was plentiful so I let taps drip at night. Also left both black and gray tank valves open so I would not over fill a tank. I posted a thread about the same subject and was told about an opening under the bed that goes to one compartment but on our model Journey the warm air does not get to the water heater area. One suggestion that would work is to put a hot pad next to the water heater pipes but I'd really suggest moving to a warmer climate. I don't know if the heated wire would work if dry camping and using the inverter - I know my electric mattress pad will not operation on the inverter power.
Safe Travels
Bob

["007"]

Do you have heat from furnace to your tank compartment and water closet areas?

[hdmoxness]

That the hot water line(s) is freezing first has not to do with the water temperature, but rather the pipe location that is getting the most freezing air. For info on insulation of a couple of key water areas, see
http://www.irv2.com/forums/f101/insu...tml#post728784.

I have been able to get rid of my 200W heaters and 100W drop lights! Good travels and stay warm!

[Graniteman]

Originally Posted by Clay L

I have heard that hot water lines freeze first and it didn't make sense based on the thermodynamics course I took in college.

So I took two identical cups, filled one with hot water and one with cold. Put them both in the freezer and the cold froze first.
I have done the experiment a number of times over the years and the cold water always freezes first.

Our 6th grade class did a similar experiment (almost 30 years ago). We had different results 2 styrafoam cups were placed on the window sill in freezing weather. The hot water developed a small layer of ice on top first. Teacher 1---Sixth grade class 0.

[Graniteman]

Originally Posted by Graniteman

Our 6th grade class did a similar experiment (almost 30 years ago). We had different results 2 styrafoam cups were placed on the window sill in freezing weather. The hot water developed a small layer of ice on top first. Teacher 1---Sixth grade class 0.

Yikes!! Just checked my math....35 years ago!

[Dwight]

January 1966 -- We finished converting our 1947 Flxible Bus into a MotorHome and the test run weekend the first night out it got down to -30* with a windchill of -72*.
The hot water line froze first as it did two weeks later as we traveled to Aspen Colorado for a week of skiing.

In Minnesota we have a test that is done when the night winter temperature falls to -20* or colder. We heat a pan of water up to 200* and throw it up into the outside air and the water turns into a cloud and doesn't hit the ground. Do the same thing with cold water and all the water falls to the ground.

This January we had nights when the temp stayed above freezing and the very same nights Florida had temps in the 20*s.

[Mr_D]

It's sometimes called the "Mpemba effect"

Here's a discussion of it