SELF-CLEANING HOT TUBS - ENERGY EFFICIENCY - PART II - PERIMETER LOCK
Posted by Greg Butler on Mon, Apr 12, 2010 @ 12:40 PM
This second method of insulating a hot tub is a little smarter. In theory, this is a very good way to do things. Essentially, the goal here is to forget about the bowl and to forget about the box, and to simply create a dead air space between the two. If we compare to a full-foam hot tub, instead of insulation with thousands, maybe millions, of little tiny air spaces, the goal is to create ONE GIANT DEAD AIR SPACE.
This is accomplished simply by creating a design where the exterior cabinet is completely sealed off so that no air gets out and none gets in and the process is generally simply by insulating the box really well. This is what has happened in your house! In theory, this is not a bad idea at all.
Compared to full-foam hot tubs, this method is at least as effective, and one great advantage is servicability. Simply remove a side panel - fix what needs to be fixed and replace the panel. No more "dig outs".
Although effective, and argueable better than full-foam, there are two particular issues of concern:
1. To completely trap heat, you need to completely seal the box. This will trap excess heat from the pumps as your hot tub operates and this excess heat will prevent your hot tub heater from kicking in and drawing on more electricity. (Like I said, this is better than full foam - especially when pumps are kept outside of the cabinetry). The catch however, is too much heat trapped by your pumps will often cause them malfunction prematurely. To alleviate this, you can vent the cabinetry, but by doing so, you comprimise the entire integrity of this method of insulation. In short, its a double-edged sword.
2. Secondly, water weight becomes a concern. As you turn the jets on and off in your hot tub, water will move at varying speeds. From stop to slow, to fast, stop, to fast, there is movement of very heavy water. With lines simply "hanging" from the jet bodies in the hot tubs, leaks are more prevelant over time. Easily fixed leaks mind you, but leaks nonetheless.
In summary:
A perimeter lock is a good method of insulating a hot tub. In theory, it is a good way to do things.
It has less limitations over full foam, but has a couple of issues that make it not ideal.