Gas or Heat Pump - Austin, Tx - daily pool use

[mybiz]

Hello everyone! Thanks for having a forum and all the useful info!

We're planning on installing a solar pool heater, but don't think it will be enough to keep our pool 82 degrees March to Nov, so we need to add supplemental heat. What's your experience with using a gas or heat pump? We've had several gas pool heaters in the past, but after having a $300 gas bill a few times, we're gun shy. It definitely heated things up fast. I've done lots of research, and my main concern is heat loss and reheating the pool; especially since we have a lot of shade. It would really help to get some feedback from others who've had a pool heat pump. Can anyone help?

 

[ps0303]

I've done lots of research, and my main concern is heat loss and reheating the pool;

Invest in a solar blanket no matter what you decide on. It will help keep the heat in the pool when not in use. It will help keep the heat in and prevent heat loss when not in use. If you do not so this, then heating your pool is a loss to a degree. Heating with gas will obviously heat up quicker than a heat pump.

 

[chrs]

We have both solar and a gas heater. Neither would be effective without the solar blanket which it sounds like you have.
We live in AZ though, so our sun will generally be more intense which means you'd need more solar surface area to get the same results - not all solar installs are the same sizing.

If we have a good week in late January, we can go swimming in 85F+ water with just the solar. BUT, we have a 2 story house, and the pump works hard during the day for at least a week to get the pool to that temp. and we'll typically lose 5 degrees by the time we cover it again later that night.

Sizing the solar properly would be key! Perhaps at that point you could give it a small temp bump with the gas heater when needed.

Also, our solar was installed with a cross-over small tube before going to the roof that connected with the pipe coming down from the roof. it's for drainage from the roof and the installer said it would prevent the pump from being fully blocked if the valves were closed going to the roof. Regardless, I installed a temp sensor after that cross-over tube so i could see the actual temperature going back into the pool and not just the temp of the water coming down from the roof. I know this is more than you asked for, but that extra temp sensor was key to optimizing our water flow through the solar so we weren't fooled by the temp sensor pre-cross-over. If the water flow was too slow, our pool didn't get warmed up.

 

[pooldv]

Solar plus a solar cover will likely get you where you want to be most of the time. I would do a heat pump if you plan to maintain a certain temp all the time and a gas heater if you want to heat it up quickly occasionally. Only if you have natural gas service. I would skip propane altogether.

 

[rphpool]

Hello everyone! Thanks for having a forum and all the useful info!

We're planning on installing a solar pool heater, but don't think it will be enough to keep our pool 82 degrees March to Nov, so we need to add supplemental heat. What's your experience with using a gas or heat pump? We've had several gas pool heaters in the past, but after having a $300 gas bill a few times, we're gun shy. It definitely heated things up fast. I've done lots of research, and my main concern is heat loss and reheating the pool; especially since we have a lot of shade. It would really help to get some feedback from others who've had a pool heat pump. Can anyone help?

In our brutal Texas heat your pool get's below 82 in the summer ??? I wish I had your problem, that time of year we are at 90-92 in pool.

 

[rick999]

In our brutal Texas heat your pool get's below 82 in the summer ??? I wish I had your problem, that time of year we are at 90-92 in pool.

I'm in New Orleans. I did my own solar and never cover the pool. This is my first year and thus far I am super pleased, but now I will be going through my first fall and winter with my solar collector which Ive added onto this summer expanding the capacity. Afte a few months of use in the spring, I threw the solar blanket away....too hard to take on and off and wanted to be able to see the pool with the LED lights....I feel bad for people who need to do this task each day....yuk! The solar gives me the bump every day I need to recover the 2 degree night loss, but with all the rain this summer I needed the solar running anytime we got sun to bring it back up. I try to keep the pool between 88 - 92 which has not been a problem so long as I get 3 - 4 days in a row of sunshine at 6 -7 hours a day. The pool only got down into the low 80s after a full week of rain....luckily that was the worse.

I was getting a 4 degree mid day differential between the pool and return from solar, but noticed this past week that I am now down to a 3 degree differential with the sun now lower in the sky. So.......I am looking to supplement and get ready for winter. We are going to try to use the pool through the entire winter.

I know I can get into mid November, but it's unknown past that what impact my solar "array" will have. I'm lucky with the position of the pool......I was able to build an aluminum canopy that can be assembled in an hour that I will put up late Nov and will be covered with a special greenhouse reinforced plastic. That will form the "cover" for the pool. Under the canopy I have 2 Bromic Heaters that should cover the pool area and provide body warmth. Will see if the canopy holds in enough heat and keeps evaporation low thereby keeping the pool from losing too much heat. Want to see how far I can push this so that I dont need a pool heater, but I doubt I will make it though winter....but this is a kind of fun experiment.

Looked at Nat Gas heater, I dont need a big one, but the only line I have nearby is too small. The cost to get a new line run is well over a thousand, and therefore making the Heat Pump a better choice, especially considering the running costs. The only downside is the size of the Heat Pump.

I've pre wired a 240 service for a Hayward HP21004T heat pump and the pad ready to go once and if we get to that point....and if we find that we enjoy using the pool that much through those months.

So that is my experience and plan, and I would be interested in knowing if anyone knows of a good online calculator to estimate costs for a heat pump under such conditions?

Will be happy to share my experiences and results. Ive been hunting everywhere for data as to costs, but the closest Ive ever come is "its expensive" to heat through winter, which of course is only a relative term.


Rick

approx 8000 gal 12 x 28 freeform

 

[rick999]

I thought 92 would be too hot for me, but now I love it and try to keep it there. No prob going lower, but under 86 now it seems too cold to me.

 

[Hayward Pool]

When we talk about heating trough the winter with a heat pump we need to consider the temp during this time. Most heat pumps do not work will below 60 degrees. Our website at Welcome to Hayward Residential and Commercial Pool Products has a calculator but may not give you all your answers.

 

[rick999]

When we talk about heating trough the winter with a heat pump we need to consider the temp during this time. Most heat pumps do not work will below 60 degrees. Our website at Welcome to Hayward Residential and Commercial Pool Products has a calculator but may not give you all your answers.

Average temps for us is 64 in Dec and 62 Jan which are the coolest months. There is a low ambiance I was also looking at. The Hayward site is terrible, very little info and hard to get full descriptions. Sometimes all the heaters dont even show up. Yesterday I called tech support and was on hold for 30 minutes before I gave up.

Im hoping that in conjunction with my solar collector it might get through those two months, but not sure it can heat to 88 degrees which is where I would like it.

Wish I had a gas line where the pump is. Would much rather try gas first, but running a new line is just too expensive, especially if it does not pan out in the end.

I found a great calculator this morning : SWIMMING POOL ENERGY TEMPERATURE CALCULATOR | Neil Anderson

 

[pooldv]

I think with solar, a heat pump and a solar cover there is a chance. You probably won't need to get to 88 to be comfortable when it is in the 60s outside. It is all about the temperature differential between air temp and water temp. In the spring we swim at 80 or 82 when it is in the 80s. Once it gets to 95 to 100+ we like the water between 88 and 92.

 

[rick999]

I think with solar, a heat pump and a solar cover there is a chance. You probably won't need to get to 88 to be comfortable when it is in the 60s outside. It is all about the temperature differential between air temp and water temp. In the spring we swim at 80 or 82 when it is in the 80s. Once it gets to 95 to 100+ we like the water between 88 and 92.

Im beginning to think your correct. I had been away a few days and no solar on during that time. It dropped 8 degrees after a cold front moved in. TO my surprise it was still comfortable once I got it back up a few degrees. I guess you get acclimatized to the lower temp. Im toying with the idea of a Mastertemp 125 Nat gas heater. Its only 900$ and so long as it will operate off of an existing line that I have near the pump, I think I will try it out. It would be an inexpensive trial to see if we actually use the pool enough through the winter. Maybe I will only need a bump up once a week to get it to swim temp, or that we dont use it as often. I have a gas plumber coming next week to measure the pressure. So far the solar is still holding the temp near 90. I still gain 3 - 4 degrees a day, but Im losing nearly the entire gain at night now that its so cool and Im not covering it yet. Going to add another 150 feet of solar this week to see if I can keep ahead of it. I have room for 300 more feet of 1" solar tubing. Then I have one last spot Im going to add 300' of coil. I have no data for going through Nov - Feb, so this is going to be interesting to see how the winter sun will perform.

 

[jdevers]

It honestly won't do what you hope even with the extra capacity. It will heat it more during the day, but it will cool more each night due to increased evaporative losses and radiation. The blanket eliminates the vast majority of both and leaves only mostly convective losses. The shortening days and lengthening nights just compound the issue.

Thank about it like this, to swim even in south Florida all year round requires nearly 100% surface area duplication in solar panels.

I'm further north than you guys but our summer temps aren't much different, what is different is humidity and wind. It is much drier and much windier here, without a blanket I am often cold even mid summer in our pool when it is 110 outside with absolutely no shade at all. Other weeks in June when it is 88 and humid as a swamp the water with no wind can easily be air temp and feel great.

 

[rick999]

It honestly won't do what you hope even with the extra capacity. It will heat it more during the day, but it will cool more each night due to increased evaporative losses and radiation. The blanket eliminates the vast majority of both and leaves only mostly convective losses. The shortening days and lengthening nights just compound the issue.

Hi there, you might not have seen the other posts. I will only be supplementing with the solar collectors. This is all a grand experiment...I love to tinker. So right now, in New Orleans we are in the low 80s during the day. The sun is getting low on the horizon for sure, so the angle to the collectors is getting less efficient, especially the 300' that is facing East. Though Im not getting a 4 degree difference any longer, I am getting a 3 degree water temp change for about 6 hours of the day.

The problem now is HOLDING the temp when the outside air is in the mid 80s. I finally bit the bullet and put the solar blanket on the pool for now because I have guests arriving this weekend. With the solar blanket on, I am gaining about 2 degrees a day with the solar running 7 hours a day. In only loses 1 degree over night....the evening temps are in the 60s now Thats in contrast to losing 4 or 5 degrees overnight without. Also notable is the evaporation. I was loosing a LOT of water without the cover when it got cool. With the cover Im losing next to nothing. I only take the blanket off now to swim an hour after work. I cut the solar blanket so it fits perfectly inside the pool wall....I have a free form pool. Even still, with all the excess blanket cut away, its plenty heavy. So I just get in the water, and roll it up to the end then lift it out while Im swimming.

I've spent a lot of time researching Heat Pumps. Gas is not an option because I got some quotes to run the proper sized gas pipe and its enough that warrants going to a Heat Pump which I already have the wiring and breaker in place and ready to go. I reluctantly allocated the necessary footprint for the Heat Pump and poured a freeform sidewalk around it. Still on one side against the house I can only keep about 18" from the wall. After talking to manufactures I decided to go with the Hayward HP21104TC low abient Heat pump. This is the round one, so it will help with the issue of being closer to the wall on the one side. I talked to Hayward Tech support and they told me that its made to work down to temperatures of 40 degrees. They suggested having it exposed to sun, which it will be. They claim that even in the 40s it should keep the pool in the upper 80s. If this is true, it will exceed my expectations, because for most of the winter, the temps are usually in the 50s during the day except for a few days in the 40s.

Once my guest leave next week I will erect the canopy over the pool. I'm hoping with this greenhouse reinforced plastic it will produce some heat as well under the canopy, and prevent evaporation.

For now I am at 87 degrees using the solar collectors. Not sure how they might assist the Heat Pump or if they can be used at the same time but I'll be happy to share the results of my winter experiment. Heat Pump is on order but I probably will not get that installed until mid November.

 

[pooldv]

Yes, solar and heat pump can work together. Mine goes to solar first and heat pump second. The solar cover helps a lot overnight. I'm interested to see how the plastic sheeting works. I think it will work great. A friend in Dallas had a 20x60 greenhouse made with plastic sheeting for over wintering tropical water lilies and it was over 90 in there in February with no heat source at all.

 

[rick999]

Well I just ran into my first problem with the solar coils I build. To my horror today I saw a huge stream of water shooting up. I inspected and found that squirrels have chewed through. I also noticed that the 2" PVC pipe feeding the coils had deep chew marks from the squirrels.

I did not know they would do this to plastic. Normally their too busy chewing my lead air vent covers.....then again I noticed that the ones I replaced 2 years ago are nearly completely chewed away, so maybe the coils are the next best thing!

The PVC is easy to fix but the coils are not going to be as easy.

The only solution I can think of would be to cover them with acrylic clear panels.

I've never heard of Squirrel damage before, anyone else???

Might have to get myself a sniper rifle!!! Dang...if I were not in City limits!!!

Pool heater going in next week, looks like that is just in time.

Rick

 

[pooldv]

Wow! Bad squirrels!

I already hate squirrels, we have a bunch of them. My dogs used to catch them but they decided they don't taste good. For a while they would chase them for sport but now they don't even bother to get up. Now a rabbit is another story, apparently they like rabbits.

They've never chewed on any of my plumbing. Yet ... They munch on our outdoor cushions and pull the batting out for nests. again

 

[rick999]

Finally got my Hayward HP21104TC low abient Heat pump installed late last week and just in time, because temperatures haven fallen a lot at night.

The heat pump was installed by a Hayward authorized pool company, but they would not do the electrical connection because they were expecting a disconnect box behind where it was going. I thought they would run a whip to the breaker box which was 8 feet away. So I called up my AC guy thinking its the same as AC, and he said yes and came over and ran the flex conduit and installed a disconnect and new breaker in the panel box (50 Amp). Also ran a ground wire to the pump where it connected to the ground grid embedded in the pool. Cost to install plumbing 550$ and Electrical $250. Heat Pump $3300.

Just like the Hayward Pool guy said, just tell your guy to connect and turn it on. Seemed too good to be true...but YES....breaker goes on and it lights up, we push the button to raise temp to 90 and 5 min later it turns on and its running. Instantly there is warm water coming out of the jets. I measured it and there was a 2 - 3 degree temperature difference.

Heat Pump went on at 3:30pm and the pool was 73 degrees and when I woke up the next morning at 8:00am it was 86 degrees!!! By noon it was 90.

I am SUPER impressed with it. Very quiet, barely a hum from the fan, and it was not as big as I expected, smaller than the average size AC unit for a medium size home. Its been running for 5 days now and the pool has held steady at 90 degrees.

Will be interesting to see what the electrical bill will be, but judging from how often it is on compared to the AC unit, I dont think its going to have a massive increase. I'm going to compare my energy usage against the online models for cost estimates. Im hoping its not going to cost more than 200$ - $300 a month. We want to use the pool all winter.

Will continue to give you some feedback on energy costs.....I had searched months and months but could never find any info on ACTUAL costs....just people saying silly things like "an arm and a leg" so this might be the first real data available....uhh unless someone from the government actually knocks on my door and asks for one of my limbs as a carbon offset!!!

 

[pooldv]

We ran our heat pump for the first time quite a bit in October, pretty much non-stop for at least 10 or 12 days, and our electric bill was less than it was last October. So, I have no idea how much it cost. Low enough that I don't care. I am also very happy with my Hayward heat pump.

How is the greenhouse plastic sheet doing for air temp?

 

[rick999]

I could not be happier!!! The plastic is nearly clear so you see the blue of the sky. It has a reinforcing through it in a diamond shape. I sealed in the sides with regular 6mm plastic where my fence is, so now I'm as close to airtight as one can be. The temp difference between inside and outside is about 25 degrees. At night we're in the 50s and inside the plastic we are in the upper 70s, so you can sit on the steps or walk around and it is not cool. I have an infrared heater bookmakred, but Im not going to buy it until I see if I actually need it. VERY HAPPY!

Anxious to see the electrical bill but I dont think I will see much of a difference. I made some changes to our AC programming to back it off a bit (starting and stopping a little earlier and moving it up one degree, but x 30 days it adds up) so this might offset a lot of the usage of the pool heater. We have a nearly 4000 square foot home, and we keep it at 69 degrees at night to sleep, so AC for that should be the lion share of the energy.

I'm playing around with the programming now for the pump. Running full speed from 10:30am to 3:00pm at which time if sunny I put the solar collector on (getting a 3 degree difference right now). My hope is that the solar will bring it up to 92 to give me a buffer for the cooling at night. At 3:30 it goes to slow speed and the solar turns off and it runs until 7pm then turns off. At 7am the pump goes on full speed at which time I am thinking the water temp will have dropped overnight below my 90 degree set point and will kick in and begin heating the water back to 90 degrees in time for the solar to kick on.

Will see if this works,

 

[pooldv]

That sounds great!