Two questions about water temp and freeze protection

[Mlsemler]

We have been having a much colder than normal winter with several spells of days below freezing (extremely unusual for our area). However, it is supposed to warm up over the next few days with high temps in the 60s and the lowest forecasted temp over the next three days is 37. Right now the water temp is 34. So I have two questions:

1. If the water temp is low, but the air temp is not freezing, is there still a possible problem with pipes/etc freezing?
2. I have a gas heater. Could I run it to heat the spa, and then let that warm water flow into the pool through waterfall to warm up the pool water a little as well?

 

[BasicTek]

Here's a thread with a lot of info. From that thread it sounds like the air temp would need to be just below 32 for 8-10 hours or way below 32 for less. I know my pump actually turns on when the air temp is around 32 or less. Heating your water won't make much difference unless your pool is covered, or else the effect will be lost almost as fast as you are heating it (with just a spa heater).

If you could post your location in your profile and you can get more specific information from others in that area.