The Procure Inc. office is a place of weird, exciting, and unexpected debates. Today we’re writing about our most recent thought-experiment: do water softeners prevent icing inside pipes? Let’s lay down some background about chemistry and water.
What Does Hard Water Do?
Water straight from the ground is not pure. There’s going to be all sorts of things mixed in with water coming straight out of a well. Ground water contains a whole range of contaminants no matter where you live. There can be bacteria, metals, even run off and toxins in ground water. It all depends on the location.
You get hard water when there’s a high mineral content. These minerals are harmless to most people. The World Health Organization has found no adverse health effects. Some researchers believe hard water may even be healthier than regular, purified water. Unfortunately, our plumbing is not so neutral. The mineral content in hard water will often start to build up inside the pipes. Eventually, the mineral build up starts to become more and more like a clogged artery. There will be a point of complete blockage.
Blocked plumbing is not good. Blockages can cause damage to valves, pumps, heating equipment, and chillers. The narrowed flow of water increases the pressure and strain on equipment. For furnaces, these blockages are especially problematic. The various coils and heat exchangers used in how water heat often rely on narrow channels to maximize their surface area and therefore improve heating efficiency. Narrower channels block up faster. Blocked heating systems are a recipe for disaster.
Using hard-water is going to get expensive in the long run due to its damage to your plumbing. You need something to de-harden, to soften the water.
Enter The Water Softener
The most common water softener setup we could find uses two tanks: a salt-brine tank and a mineral tank. Water is pumped into the mineral tank to be cleansed. This tank is full of beads with a negative atomic charge. Most of the mineral contaminants have a powerful, positive charge. The minerals will be attracted to the beads, binding to them and being trapped inside the tank. You get cleaner water, but only so long as there’s enough beads to capture all those minerals.
To keep the water softener running, we use salt. Sodium has a powerful charge all its own, which drives the minerals off the beads. So, we’re back where we started, right? Water tank full of minerals and water? Not quite. The mineral tank is now full of concentrated minerals. We can fix this whole thing right now: dump the minerals down the drain.
We call this process a regeneration cycle. During most of the day, your water softener’s beads will do the work. When the mineral build up on the beads exceeds a given threshold, the water softener brings in the salt-brine and flushes all the unwanted material down the drain.
What Does This Have to do with Pipe Bursts?
The water softener requires a constant supply of fresh salt. If there’s one at your home or office, you probably have to give it a fresh bag every few weeks. This can lead many people to believe there is salt water in their water supply. To an extent, there is. Some measure of salt will get left in the mineral tank and escape into your plumbing. During refresh cycles, it’s possible for the water to briefly become as salty as sea water.
Salt water doesn’t freeze readily. Adding salt to water increases the boiling point and decreases the freezing point. This is why we use salt on our sidewalks and streets during the winter. It bonds to the water in the snow and ice, then causes the freezing point to change. Salt water can prevent water from freezing.
Unfortunately, the cycle and design of water softeners prevents them from helping against icing. There might be just enough salt slipping into your water supply to lower the freezing point by 1/10th of a degree. Water freezing at 31.9 degrees vs. 32 degrees won’t protect your home.
Protect the Water Softener
Your water softener itself is actually at-risk. Just as the salt concentration in your plumbing is pretty low, it’s pretty low in the main mineral tank. If your water softener is somewhere cold or unheated such as a garage or external mechanical room, you may need to provide some sort of heating to keep the softener above freezing. This can be achieved temporarily with electric heaters. It can be achieved in the long-term with insulation and some minor heating modifications by your HVAC Contractor.