STR and Pool Heaters
Real Estate Agent · Naples, FL · Member since 2017 · 48 posts · 15 votes
I'm planning on another STR, but this one has a rather large pool, where many STRs in town have a small plunge pool. In SW Florida our season is typically January-April. A pool heater will definitely make the STR much more appealing. My concern is the huge cost of the electric bill. Electric pool heaters are really expensive to run and solar heaters may not do the trick, even in our SW Florida winter months.
How do you deal with a situation like this? Do you put a limit on the electric bill and charge the credit card after the bill arrives if it's over the allowed amount? Do you bite the bullet and pay a few thouand dollars? Our electric rates have gone way up this year!
What would you say if I told you that I heat my pool in Maryland for free using the waste heat from my air conditioner and it makes my A/C more efficient as well ? About 7 or 8 years ago, I installed a water cooled condenser onto my existing A/C unit and it dumps all of the heat from my house into my pool when the A/C is running. I keep my pool at 91 degrees F all summer long and it extends my swimming season significantly. I barely used my pool in MD before I did this because I don't get in pools that are under about 82 degrees as I get cold very easily.
Here's the link:
https://www.hotspotenergy.com/...
The cost of the kit was about $1000, but you are going to need to either be pretty handy or find an air conditioning / refrigeration professional that is more skilled than your average plug and chug HVAC installer. I'm an engineer, so I did most of it myself.
I have optimized the energy consumption of my system by pairing it with a multispeed pool pump which only uses 200W when moving water through the condenser when the A/C is running.
Feel free to contact me and I'll be happy to talk with you in more detail.
I started my refrigeration system hacking back in 1991 when I lived in a college dorm suite during the summer in Illinois. The midwest gets very hot during the summer, and this dorm had no air conditioning which made sleeping at night miserable. The college banned window air conditioners, so that was not an option. We had free water in the bathroom of our dorm, and I am pretty handy. I took an old window A/C that I bought for $25 and I cut the stock air cooled condenser out of it. I then used a piece of PVC pipe and some copper tubing to make a water cooled refrigeration condenser which we connected to the A/C unit to replace the air cooled condenser. I used an old solenoid valve from a junk humidifier to turn on the water when the A/C compressor started. We tapped the water line under the sink to get our cooling water for the condenser, and then we ran a hose into the toilet where we dumped the hot exhaust water down the drain. It was kind of noisy and butt ugly, but it worked really well !
We had the only air conditioned dorm on campus which made our place a very popular place to hang out !
When I lived in Florida 20 years ago, I used a miniature version of my pool heater (called a heat recovery de-superheater) with my air conditioner to make almost all of the hot water for my house for free. Why on earth this is not done more commonly is also baffling to me. The payoff time of my investment was less than a year. It easily saved me several hundred dollars a year in electricity.
Most people don't really understand how an air conditioner or heat pump works, so I guess it doesn't occur to people to use the large amounts of waste heat from their air conditioners for something useful instead of just throwing it away into the air. Air conditioners / heat pumps don't "make" cold; they simply pump heat from one place to another. You can pump the heat out into the air, or just as easily into a pool or to heat your water.
The economics of a heat recovery system from an air conditioner are much better than that of installing a solar electric system. A semi close second is replacing a traditional electric hot water heater with a heat pump hot water heater, especially if the hot water heater is located in a garage or another space that you would want to cool and de-humidify anyway. A regular resistive hot water heater gives you one unit of water heating value for every unit of electrical energy you put into it. A heat pump hot water heater gives you about 3 units of heat for every unit of electricity that you put into it.
I started my refrigeration system hacking back in 1991 when I lived in a college dorm suite during the summer in Illinois. The midwest gets very hot during the summer, and this dorm had no air conditioning which made sleeping at night miserable. The college banned window air conditioners, so that was not an option. We had free water in the bathroom of our dorm, and I am pretty handy. I took an old window A/C that I bought for $25 and I cut the stock air cooled condenser out of it. I then used a piece of PVC pipe and some copper tubing to make a water cooled refrigeration condenser which we connected to the A/C unit to replace the air cooled condenser. I used an old solenoid valve from a junk humidifier to turn on the water when the A/C compressor started. We tapped the water line under the sink to get our cooling water for the condenser, and then we ran a hose into the toilet where we dumped the hot exhaust water down the drain. It was kind of noisy and butt ugly, but it worked really well !
We had the only air conditioned dorm on campus which made our place a very popular place to hang out !
When I lived in Florida 20 years ago, I used a miniature version of my pool heater (called a heat recovery de-superheater) with my air conditioner to make almost all of the hot water for my house for free. Why on earth this is not done more commonly is also baffling to me. The payoff time of my investment was less than a year. It easily saved me several hundred dollars a year in electricity.
Most people don't really understand how an air conditioner or heat pump works, so I guess it doesn't occur to people to use the large amounts of waste heat from their air conditioners for something useful instead of just throwing it away into the air. Air conditioners / heat pumps don't "make" cold; they simply pump heat from one place to another. You can pump the heat out into the air, or just as easily into a pool or to heat your water.
The economics of a heat recovery system from an air conditioner are much better than that of installing a solar electric system. A semi close second is replacing a traditional electric hot water heater with a heat pump hot water heater, especially if the hot water heater is located in a garage or another space that you would want to cool and de-humidify anyway. A regular resistive hot water heater gives you one unit of water heating value for every unit of electrical energy you put into it. A heat pump hot water heater gives you about 3 units of heat for every unit of electricity that you put into it.
Tanya,
If I were to do anything in that situation, I would probably try to use the heat from the heat pump when it was in air conditioning mode to heat my domestic hot water as I did in FL 20 years ago. The same company HotSpot Energy has heat recovery units that can heat domestic hot water.
One trick I learned when I did it though was to return the heated water from the heat recovery unit through a tube that extended down about 6 inches or so into the tank through another port in the top of the hot water heater instead of injecting it into the normal hot water heater outlet pipe. I originally injected the water into a T fitting on the water heater outlet pipe, but if the A/C was running and you took a shower, then the heat recovery unit would suck in very cold water at the inlet and then exhaust only lukewarm water into the hot water leaving the tank. Injecting it into the tank via a different home in the top of the tank solved this problem.
In WI, you are going to have to keep the heat recovery unit inside so the water in it does not freeze.
IDK how long your A/C season is in WI, but in FL it was 9 months of the year so we got a lot of hot water from heat recovery.
mid I owned a property that I was going to keep for a long time and I paid to heat it, I would investigate a ground source heat pump. The upfront cost is pretty high, but the operational cost is very low.