Gray water tank anti-freeze

[dcrogers]

A word of caution about using flat silicone rubber heaters that are built for heating engine oil pans in cold climates. They can get hot enough to deform and melt the plastic grey water tank. One user comments on Amazon page says, "The pad gets really hot but its OK on metal surfaces. Keep it away from plastics."

Another thought - instead of salt, how about adding some automotive antifreeze to the grey water tank? Maybe also the toilet tank. The TM manual says (winterizing): "Antifreeze may be added to the sink and tub drains to keep the drains in working condition, but freezing will not damage the traps." The amount of salt or antifreeze to add depends on expected minimum temperature and the amount of grey water. For example, the freezing point is 10°F for a solution of 75% water and 25% antifreeze. And for any such additive, there may be environmental concerns about dumping the tank.

[Tymanthius]

Originally Posted by dcrogers

For example, the freezing point is 10°F for a solution of 75% water and 25% antifreeze. And for any such additive, there may be environmental concerns about dumping the tank.

They do make pet/environmentally safe antifreeze, FYI, as well as RV specific stuff.

[Bill]

Originally Posted by dcrogers

Another thought - instead of salt, how about adding some automotive antifreeze to the grey water tank?

It is illegal to dump automotive antifreeze down a drain in many municipalities. It mucks up the sewage treatment plant somehow. I can imagine that in a campground with its own treatment plant, you would be even less popular. As you noted, there are environmental concerns.

The TM manual says (winterizing) ; "Antifreeze may be added to the sink and tub drains to keep the drains in working condition ..."

I'm pretty sure they meant non-toxic RV antifreeze.

Bill