Gas Pool Heaters & Potential Dangers

Sean Griffin, November 25, 2009

jandy pool heaters need to be properly installed
Gas fired swimming pool heaters allow the homeowner to enjoy their pool and spa at their desired water temperature without the limitations of solar or electric pool heaters. With advancements in technology a gas heater can be activated as easily as a push of a button on wireless remote. A heated pool can run longer into those colder months, for those who experience freeze, allowing you to enjoy your pool more months out of the year. But there is a dark side....

The ease and comfort of your pool heater should be enjoyed only after proper installation. Mistakes when installing your pool heater can lead to serious complications including death. When taking a look at the installations instructions you will notice several warnings in bold writing. They all have a similar message…
A little intimidating, as it should be. A qualified professional should be used to install a gas pool heater. According to Jandy, a manufacturer of pool heaters, “Experience has shown that most operating problems are caused by improper installation.” Read the manual - it has very specific instructions to safely install a gas pool heater. If you don't understand them, you are probably not qualified to install a gas pool heater safely.
There are several components to a heater to install to include: Gas, electric, and plumbing. Proper ventilation and correct placement are very important when installing gas pool heaters. Exhaust from gas pool heaters contains toxic levels of carbon monoxide, a dangerous and poisonous gas. According to a 2004 report from, “Carbon monoxide poisoning may be more common than is currently recognized. It iscarbon monoxide poisoning in pool heaters conservatively estimated that in the US there are at least 200 deaths per year from carbon monoxide poisoning.”
An unfortunate example as to the importance of proper installation procedures is the case of former tennis star Vitas Gerulaitis. The retired tennis super stars’ life was tragically cut short due to carbon monoxide poisoning as he napped in the room directly above the pool equipment at a friends’ house. Insufficient ventilation led to a deadly amount of carbon monoxide that resulted in his untimely death.
Carbon Monoxide is an odorless and invisible killer that needs to be treated as such. Symptoms of carbon monoxide poisoning include dizziness, headache, nausea, weakness, sleepiness, muscular twitching, vomiting and inability to “think clearly”. Excessive exposure can result in brain damage or death. According to Pentair, a manufacturer of residential and commercial pool heaters, “If you experience any of the symptoms, immediately turn off the pool heater and leave the vicinity….and get into fresh air immediately. The pool heater must be thoroughly tested by a gas professional before resuming operation.”
Pentair had a recall of the NT series Minimax Pool Heaters in 2007 for Carbon Monoxide hazards. Read the CPSC recall.
To reiterate, a gas pool heater is an item every pool and spa owner should consider having but keeping in mind the potential dangers. As I discussed, proper installation is a must along with proper maintenance performed by qualified personnel. Other potential dangers outlined in owners’ manual include flame roll-out. Roll out occurs when the unit doesn’t have proper ventilation and gas accumulates within heater. This causes flames to come directly out of the front of the unit.
Flame roll out is also a fire hazard and also creates the possibility of bodily injury especially if you have your face down in the heater trying to manually light. I have also seen people injured simply in trying to get away from a heater that has created rollout accompanied by a loud “Woosh”. Make sure debris is removed from top of heater and soot or corrosion on the heat exchanger is not blocking the burner exhaust. 
During those months when your heater is not in use make sure to properly winterize. To help gas pool heaters deal with the weather, consider investing in a heater cover. Another bit of required equipment for heaters that must be installed indoors is a Carbon Monoxide detector. This early warning device could save a life.