Determining Efficiency of a Gas Pool Heater

Determining Efficiency of a Gas Pool Heater

New gas swimming pool heaters have a standard test they go through to determine their energy efficiency based on their Btu (British thermal unit) output.

Heater efficiency is the ratio of usable output to energy input. For example, an 80%-efficient heater uses $80 worth of useful heat for every $100 worth of fuel. Therefore, it wastes 20% of the fuel.

Most gas pool heaters feature their efficiency percentage on their nameplates. A pool heater’s manufacturer can also provide its efficiency percentage.

Today, you’ll find some gas pool heaters with 89%–95% efficiency. The following table shows how much you can save for every $1,000 in annual pool heating costs by installing a gas pool heater that’s 95% efficient.

Sizing a Gas Pool Heater

Sizing a Gas Pool Heater

You should have a trained pool professional perform a proper sizing analysis for your specific swimming pool to determine pool heater size.

Sizing a gas pool heater involves many factors. Basically, a heater is sized according to the surface area of the pool and the difference between the pool and the average air temperatures. Other factors also affect the heating load for outdoor pools, such as wind exposure, humidity levels, and cool night temperatures. Therefore, pools located in areas with higher average wind speeds at the pool surface, lower humidity, and cool nights will require a larger heater.

Gas pool heaters are rated by Btu (British thermal unit) output. Outputs range from 75,000 Btu to 400,000 Btu.

To calculate an approximate heater size for an outdoor swimming pool, follow these steps:

1. Determine your desired swimming pool temperature.
2. Determine the average temperature for the coldest month of pool use.
3. Subtract the average temperature for the coldest month from the desired pool temperature. This will give you the temperature rise needed.
4. Calculate the pool surface area in square feet.
5. Use the following formula to determine the Btu/hour output requirement of the heater:

Pool Area x Temperature Rise x 12

This formula is based on 1º to 1-1/4ºF temperature rise per hour and a 3-1/2 mile per hour average wind at the pool surface. For a 1-1/2ºF rise multiply by 1.5. For a 2ºF rise multiply by 2.0.

How Much Money Can You Save With A Variable Speed Pump?

Can you save money if you upgrade your pump to a variable speed pump?

If you spend the extra money and install a high efficiency variable speed pool pump, how long will it take for your new pump to pay for itself? If you are looking for the quickest way to calculate your savings, you should look the Jandy Energy Cost Estimator.

If you want to get a better understanding of how a high efficiency, variable speed pump saves you money, read on. Your total savings really depends on several factors:

The size of your current pump and the current cost of operation
The size of your pool and the number of hours it takes to complete a filtration cycle
The flow requirements of other water features (waterfalls, raised spas, cleaning systems)

In order to understand your savings, you need to understand how much your old standard pump is costing you to operate. Find the HP rating on your pump and then go across the chart to find the annual cost if you are running 8, 10, or 12 hour cycles.

We are going to use a 24,000 gallon pool for the sake of this chart.

Find your pool size and you will see how much flow is required to pump the entire volume of your pool though your filter in one twelve hour cycle.

If you have a raised spa, you will want to increase the RPM by 200 – 400 RPM to get a nice overflow. If you have other water features such as Rockfalls, Sheer Descents or Laminar Jets, you will also have to account for the flow required by those features.

Most of the time we also program a higher RPM for two hours per day while the cleaner is operating . Even with these higher speeds, the overall cost of operation is still significantly less than the older, less efficient pumps.

When it comes time to replace your pump . . . if you go with a variable speed pump instead of a standard pump, the cost difference between the two is about $750.00. In most cases, you recover that additional expense in just a year or so.

24,000 Gallon Pool, 2.0 HP Pump Annual Savings: $549.99 Payback Time: 16 months

If you have a 24,000 gallon pool with a 2.0 HP pump that is running 8 hour filter cycles, you are currently spending $709.86 per year on your energy bill. If you go with a variable speed pump you will spend about $159.87 per year on your energy bill. That is an annual savings of $549.99!

The cost difference between a standard 2.0 HP pump and a variable speed pump is $750.00. You will recover this cost difference in about 16 months. After that, it will continue to pay you back dividends month after month.

24,000 Gallon Pool, 1.5 HP Pump Annual Savings: $462.09 Payback Time: 21 months

If you have a 24,000 gallon pool with a 1.5 HP pump that is running 8 hour filter cycles, you are currently spending $621.96 per year on your energy bill. If you go with a variable speed pump you will spend about $159.87 per year on your energy bill. That is an annual savings of $462.09!

The cost difference between a standard 1.5 HP pump and a variable speed pump is $800.00. You will recover this cost difference in about 21 months. After that, it will continue to pay you back dividends month after month, for the entire life of the pump (normally at least ten years)

Good question!! If you have water features such as a spa that overflows into your pool, or a water fall that runs all the time or sheer descents, then you may need to run the pump at a higher speed to make these work properly. We can also adjust the valves to push more of the water to these features.

We will generally also program the pump to a slightly higher speed for 2-3 hours per day to create a “cleaning cycle” to coincide with the run time on the automatic pool cleaner so that the skimmers and the main drain more effectively pull in the debris.

With a variable speed pool pump, there is a balance between economy and performance.

If you choose maximum energy savings, you will probably save 75% or more on your pool energy costs, but your pool may not stay as clean. If you choose maximum performance and run the pump at higher speeds, you will keep you pool as clean as you did with your old single speed pump, but you will still save 40 – 50% on your pool energy costs. Either way . . . YOU WIN!!

Enjoy the water a little longer!

Enjoy the water a little longer! A natural/propane gas pool heater allows you to extend the swimming season.

The most effective way to maintain ideal water temperatures, natural/propane gas pool heaters are up to 97 percent energy-efficient and warm the water twice as fast as electric heaters, according to the American Gas Association.

Natural/Propane gas pool heaters are available for any size pool or spa, and there are also a variety of natural/propane gas heaters for spas and hot tubs. When installing a new natural/propane gas heater for your pool or hot tub, always have a qualified gas contractor do the work.

Gastek Pool & Gas Services, LLC. is your gas heater specialist in the greater Tampa bay area. Call Gastek Pool & Gas Services, LLC. today (813) 335-7491 to get your gas heater repaired or replaced.

Gastek Pool & Gas Services

Rodent damage to pool heaters

Rodents can destroy a pool heater. We can rodent proof your heater to stop them from destroying it. Give us a call (813) 335-7491 and get us out there to stop them!

Variable Speed Pool Pumps

Do you need a new pool pump? How about a variable speed pump.

Variable Speed Pumps, a Modern Marvel

Variable speed pumps are an entirely different animal. Unlike the inefficient induction motors used in single and two-speed pumps, variable speed pump utilize what’s known as a permanent magnet motor. This is the same type of motor used in electric cars. They allow the user to “dial in” the exact flow rate they need for their pool allowing them to capitalize on the golden rule of pool circulation: slower is better. The idea is that by reducing the flow rate of water, there is less friction, which makes the entire system dramatically more efficient.

They are also much quieter, vibrate less, run cooler, last longer, are digitally controlled, and have advanced diagnostics. Basically, variable speed pumps are the Cadillac of pool pumps, and most studies show that they are 90% more efficient than standard one-speed pumps. This typically equates to an operating cost of approximately $20-$30 per month. Keep in mind that the initial cost of a variable speed pump will be more than two times the cost of a regular single speed pump. You will have a savings in electricity down the road which will pay you back.

Keep in mind that Chapter 4 of the 2010 Florida Energy & Conservation Code provides the specifics, which requires the following:

a. Residential filtration pool pump motors can not be split-phased, shaded-pole or capacitor start-induction run types.
b. If the total horsepower (HP) of a residential filtration pool pump or filtration pool pump motor is one HP or larger than the pump and pump motor must have at least two speeds.
c. Residential pool filter pump controls, for use with a multi-speed pump, must be capable of operating at a minimum of two speeds.

Need a new pump? Gastek Pool & Gas Services can provide you with a quote to either replace your pump or upgrade it to a variable speed pump. Gastek Pool & Gas Services of Tampa can be contacted at (813) 335-7491

Gastek Pool Variable Speed Pump