Never drain your hot tub

Nothing makes a hot tub repairman cringe more than hearing “it stopped working so we drained it.”  So, to make sure the point is well made:  NEVER Drain Your Hot Tub in the Winter!

Whether you use a pump or the built in drains, there is one fact that you can be absolutely, positively sure of:  When your hot tub looks empty, there are still 5-10 gallons of water trapped in the pipes that you can’t see.

There are two reasons that you can’t completely drain a hot tub.

First of all, some of the internal pipes are physically lower in the tub than the drain.  Even if the drain is on the bottom, a modern hot tub has close to 100 feet of pipes and tubing, and some of those are going to be at the bottom of loops or traps where gravity will not empty them out.  A good analogy is the “trap” under a sink in your home.

The second reason you won’t completely remove all the water is because as you drain your  hot tub, air gets into the pipes and creates pressure traps that prevent water from escaping.  An example is if you’ve ever drained your hot tub, then removed a cap on a water diverter, restrictor, or sometimes even a filter, you’ve seen water suddenly drain into the tub even though you thought it was already empty:

The reason you never drain a hot tub when the outdoor temperature is below freezing is that water left behind in the pipes will quickly freeze, and as it expands it can break your pipes, pumps or heaters.

If the hot tub stops working, how long do you have until it will freeze up?  Compare a puddle of water on the street to a lake in the park on a day when the temperature is 32 degrees Fahrenheit (That’s 0 degrees Celsius to the rest of the world).  How long does it take for that puddle to freeze solid?  A few hours maybe.  How about the lake?  Even if the surface gets a coating of ice after a day or two, how long does it take to freeze solid?  A few days?  Weeks?

When you drain your hot tub in the winter, you are taking 300 or 400 gallons of water, all of which is heated and would remain liquid for days, and removing it so you have only five gallons left which can freeze in a few hours.

The final thought for this post is, what do you do when your Hot Tub stops heating?  First of all, if the hot tub is still powered up and the pumps are operating, the tub will run the pumps to move water and generate friction, which will prevent the water from freezing.  In climates with temperatures no more than 10-15 degrees below freezing have no worries.  But still check it frequently, just to make sure.

If you have no power at all, then get heat into your hot tub.  This article about Hot tub protection using an electric space heater will tell you how.

We are available year round to help with your hot tub, however there is a limit to what we can do based on the weather and how your hot tub is physically installed.  For more information or to schedule a service call to resolve your hot tub problems, contact us at 201-897-7900 or 732-894-4494.  You can also reach us by email through this link.