People generally buy swimming pool heaters for 1 of 2 reasons:
- Replace a failed or worn out heater
- New installation of a pool heater
If you are replacing a pool heater and the heater performance over the years has been satisfactory then your search will be rather easy, just find the direct replacement! It can be easier to install a direct replacement heater, because the water and gas pipes will usually line up, making things much easier for you.
New pool heater installations are most easily installed at the same time of the pool construction. This option is the most versatile and easiest since you work it into your design plan. Fortunately, my guidelines for making a wise choice are going to help you make an informed decision, whether you are building a pool and considering a pool heater, or if you are thinking about adding a pool heater to your existing pool – retro-fitting, as it were.
First, you need to make 3 decisions about a new pool heater:
- Which type of pool heater to install?
- Gas pool heater (Natural or Propane gas)
- Electric heat pump pool heater
- Solar pool heater
- What pool heater budget do you have?
- How fast do you want the pool heater to raise water temperature?
- Gas pool heaters are the most reliable choice if you want to heat a Spa up fast.
- Pool heat pumps add 1-3 degrees per day, and don’t work well in cold weather.
- Solar pool heaters can heat fast, on hot days, but are slower and less efficient in cold weather.
What’s the Best Type of Pool Heater For You?
Before choosing a specific pool heater you must figure out what type is going to fulfill your needs. The speed of the heating is usually going to directly affect the cost of running it. Gas heaters, natural or propane, are going to give you the fastest heat with the highest running cost. Heat pumps are slow and steady, but more often than not will be a cheaper monthly bill. Solar heating will also fall under the slow and steady category, but the only cost to run this type is running your circulation pump, which you are already doing. Although the cost of operation is a huge factor in your decision, the initial cost of the pool heater may affect your decision.
Once you have chosen a type of heater and have properly sized it to your pool and your expectations, you can now look into the logistics of installing the new pool heater. If choosing solar pool heating, an amount of solar panels equal to at least 50% of the pool’s surface area should be installed. If you do not have the room to fit them, then you will not be able to maximize the potential, however, every little bit of solar panel will add heat.
How Much Does It Cost to Install a Pool Heater?
Gas pool heaters should be installed by a qualified contractor. It involves pvc plumbing, gas plumbing, electrical wiring and possibly proper venting. These can be quite hazardous if done incorrectly, so if you do install your own gas pool heater, make sure that you are qualified to perform these technical tasks. If you were to call in a contractor to replace a gas pool heater for you, it could likely cost at least $400 – 500. If the installation is new, and there was no previous gas heater, the installation cost will likely also require running a gas line (Natural from the meter to the heater, or installing a 200-500 gallon propane tank). Typically, large propane tanks are leased from a local propane supplier, who will connect it to the heater at the time of tank installation. The LP propane truck will come around every so often during pool season to keep the tank filled. If a gas pool heater is installed near, under or inside of a structure, proper HVAC venting must be installed for carbon monoxide safety. New gas pool heaters will also need a non-combustible concrete slab to be placed on.
Heat pumps require a dedicated breaker to supply power to the unit. Depending on the size of pool heat pump, a 30-60 amp breaker is needed. If you have room on your pool equipment sub-panel to add the breaker, that’s good! If not, you’ll need to “heavy-up” the electrical service to supply enough power to the heat pump. Either way, you may need to contract the services of a qualified electrician. Besides the electrical hook-up, a pool heat pump needs to be placed on a solid, level surface, and connected to the pipe coming out of the pool filter, and to the pipe going back to the pool. Similar to gas pool heaters, a company may charge $400 – 500 to install one that you buy online.
Solar pool heaters may be the easiest to install, with the exception of possibly involving steep roof lines. Panels are unrolled and secured to the roof, rack or just laid on the ground. The solar panels are connected together at the ends of the 10 or 20 foot lengths. Then, the pipe is cut after the filter to direct the water into the solar panels, by the use of a 3-way valve, which can bypass the panels when solar heating conditions are poor. Larger solar pool heaters work best with the optional solar controller, which will automate the 3-way valve, and send water to the panels only when conditions are right. Solar pool heater systems may be easier to install than gas and ‘lectric pool heaters, but larger systems will take more time. The average solar pool heater system can be installed for under $500, if done by a contractor.
Solar panels are a perfect diy pool heater project that is not overly technical. For gas pool heaters, homeowners can usually do the labor of receiving the new heater or heat pump and placing it on a sturdy, level slab next to the pump and filter. Some of you can even wire up the heater or make the plumbing connections to install the heater into the plumbing loop, after the filter and before a chlorinator. Installing the gas supply however, Natural or Propane, should be certified by a qualified gas contractor, before the heater is tested.
How Big of a Pool Heater Do I Need?
Let’s touch on gas heater and heat pump sizing. The best way to try to simplify pool heater sizing is this calculation:
Pool Gallons x 8.33 x Desired Temperature Rise / 24 hours = required BTU’s.
Keep in mind that a gas heater will need a larger BTU output because of efficiency. Typically a pool heater can range from 75-90% efficient, which means every BTU will yield roughly .75-.90 BTU’s of output. A heat pump is quite different, and can potentially provide 3-6 times more heat than the input BTU. If you undersize your pool heater, no matter the type, the result will be slower and lower temperature rise, longer operating time, and shorter seasons.
How Much Heat Will a Pool Heater Add to My Pool?
A huge aspect of choosing your new pool heater is, what you need or expect the heater to do. A temperature rise of 20 degrees may be easily possible in your situation. You can base your decision off of when and how you’re going to be using the pool. If you’re looking to dramatically extend the swimming season, or even to heat your pool or spa year round, a gas heater is going to be the best choice. Although they are usually the most expensive to run, they do not depend on air temperature or sun exposure, which is usually low and in short supply in the colder months. A gas heater will also be your best option if you are more of a ‘weekend warrior’ in regards to pool use, and are looking to quickly raise water temperature.
A heat pump will be able to add up to a few weeks to a few months onto both ends of your swimming season. They rely on drawing warm air, so without that, they become inefficient and usually will not function well below 45-55 degrees Fahrenheit. For economical pool heating, however, and if you are an everyday pool user, a heat pump will be a great fit. Heat pumps heat slowly, and despite the large amperage circuits that run them, they run very efficiently and can operate for $1/day in most cases.
Solar pool heating is going to have the shortest effective range out of the main types of pool heaters. Solar, like heat pumps, must have warm temperatures to be functional. Not only does a solar heater need warmer temperatures than the current water temperature to work. In other words, a 75 degree day with 65 degree pool water would allow the solar heater to make up that 10 degree difference. Conversely, running your solar heater on a 65 degree day with 75 degree pool water would in fact cool the water. Some customers will even take the extra step and use a solar heating system in conjunction with either a gas heater or heat pump. This will give you the extension of the pool season you’ve been looking for with very low operating costs in the warmer months.
Each of these heating options will be an outstanding addition to your swimming pool, and depending on the situation will be extremely effective in taking the chill off of the pool. I would like to finish by telling you that no matter which heating option you choose, a solar blanket is a necessity when using a pool heater. The biggest factor in heat loss is going to be the surface area of your pool, which can be minimized by using a solar blanket, solar pool rings, or liquid solar.
I hope that this has helped you in your plans to add more heat to the pool. As always, we are here to help! If anything about this entry has confused you or you need something cleared up we are ready and able to assist you at 800-983-POOL.
SPP Pool Expert