Is a Bigger Pool Heater Better?

People have pool heaters for various reasons.  Some people have a spa in which a pool heater is required.  Some people like to have warmer water in their swimming pool.  Personally?  I hate cold water.  Some people like to extend their swimming season for months, which is what you can do if you own a swimming pool heater.  Whatever the reason, heaters are fun!

Heaters are plumbed into your equipment pad.  You may also have a salt system or in-line chlorinator.  All swimming pools have a pool filter.  If a heater is added, your pool water makes another stop on its way back to the swimming pool.  As the water is drawn from the skimmer and/or main drain it then gets pushed back through the system before returning to the pool.  If you have a heater, as the pool water passes through it gets heated either by electricity or gas.

Is a Bigger Pool Heater Better?

Heaters are measured by the heat output.  This is measured in British Thermal Units (BTUs).  The higher the BTU, the larger the heater.  When we are talking about heater size, we rarely are referring to the dimensions.  We usually mean the BTUs, not the measurements.  Measurements can be important too, especially if you have limited space on your equipment pad.

The larger the heater (higher BTU), the more quickly it will heat your water.  This means it is more efficient.  You have to run it less so it saves you money.  You won’t have to wait as long for the water to be enjoyed.  

Pro Tip:  Always go with the highest BTU your pool can accommodate.  If using a gas heater, you are limited by both the size of your gas line and the length of the run.  Electric heaters do not have this restriction.

There are 2 major types of swimming pool heaters:  Natural Gas and Electric Heat Pumps.  Let’s talk about the difference and which heater may be right for you and your swimming pool needs.

Natural Gas Heaters

These are more efficient if you only want to heat your swimming pool for shorter periods of time.  They also heat the water more quickly–especially the spa.  They generally are not used for maintenance heat in your pool, although they can certainly be used in the application.  They are great for the colder climates that dip below 45-50 degrees Fahrenheit as they do not rely on the outside air for heat production.  You do have to pay for the gas. 

Depending on a couple of factors will determine how long you have to run your pool heater.  BTU is one of them.  Other factors include where your water temp is versus where you would like it to be.  The size, measured in gallons, also plays a key role.  If gas is expensive in your area or you have solar, you may want to consider a heat pump

Heat Pumps

Swimming pool heat pumps do not run on gas at all.  They are not only environmentally friendly, but efficient.  Heat pumps tend to lean on the lower side of annual operation than that of a natural gas heater.  Looking for longevity?  Heat pumps have a longer life span.  This of course depends on your water chemistry.  Poor water chemistry can ruin any type of heater.  As the outside air is extracted, a compressor is utilized to increase the heat and warm the water as it passes through.  Usually 3-5 degrees per pass.  The heat pump then ejects the cold air out of the top of the unit.  If you live in a region that gets below 45-50 degrees then a heat pump probably isn’t for you.  Unless, of course, you plan to use it “season only”.  If electricity is expensive in your region, a heat pump may not be for you either.

Heat pumps are meant to be left on to keep the water’s temperature maintained.  They are not designed to heat water quickly.  I am sure you can see why a larger BTU makes sense with an electric heat pump as well!  The usage is measured in watts/kilowatts.  Grab your electric bill and see what your charge is for this and you can gauge how much running your heat pump for 24-72 hours will cost you.

Heater Costs

Heaters are not cheap.  I say this because of how awesome they are, but who knows.  If you were to go to your local swimming pool supply store to price a heater, don’t be surprised to see a price tag of around $4,000k.  Heat pumps can be a bit pricier still.  If you have decided a heat pump is right for your pool, I have some fantastic news.