Browse Forums Pools & Spas 1 Sep 13, 2015 10:09 am I'm in the process of gathering quotes for heating our pool and trying to decide on the best way to go about it. After a bit of searching there appears to be very little here specific to pool heating so I thought I would share my thoughts and ask if anyone has any experience that could benefit both myself and anyone else that may search for any info on pool heating. First the questions; what system? Gas, heat exchanger, evacuated tubes, glazed panels, black poly panels and or the flexible matting? Gas and heat exchanges offer the greatest extension of swim time but cost the most to run. The place where I would put a heat exchanger is right alongside the heat exchanger for our main reverse cycle aircon unit and I've often thought it would be great to combine the two to heat the pool and cool the house from the same unit. I haven't really looked into evacuated tubes for pool heating. They seem to be better suited to adding a lot of heat to a small body of water. Pool systems I've seen use evacuated tubes via a heat exchange system. There aren't to many glazed panels on the market. They are maybe more efficient and use less roof space than the conventional matting. I believe these must be installed so that they can completely drain when water is not being pumped through them. The black poly panels reduce the amount of connections on the roof and the potential for leaks. The little tubes are closer together which maybe makes them a little more efficient than the flexible matting. Most panel systems are interconnected via barrel unions or something similar which reduces the risk of leaks. There is one system that uses a solid panel interconnected via silicone tube and hose clamps. This system has more connections than the others and I would love to hear some first hand experience of these. The flexible matting is the most cost effective and probably the most common. It easily fits odd shaped roofs but has the most connections on the roof and the greatest potential for leaks. Gas heaters and the heat exchanger or too expensive to run for me. I'm just not looking at the evacuated tubes, they're probably not best suited for flat roof. I have to run the pipes to the roof up and over the parapets which means while my system can depressurise it can't completely drain out so the glazed panels are out. I have a metal flat roof with box gutters and am very concerned about leaks so the flexible matting is out making the panels the system of choice. I have 5Kw of solar PV with a pay back of 52c a Kw/h so I want to make the most of that and ensure the system is as efficient as possible. The booster pump needs to run during the day so tariff 33 makes sense, it's not to hard to do and will make the most of my PV system. I have an existing pool and filter with an eco pump so I have to 'tap' into the existing filtration to run the solar booster pump. I plan on supplying both pumps from the same point and connect the pipe coming back from the roof in behind the chlorinator. Both pumps will run independently and never on at the same time. The main eco pump will remain on the normal un-switched power supply and will be controlled via the existing timer to operate outside of peak solar PV output time (6-8am & 5-7pm). The solar booster pump will be on tariff 33 and controlled via the solar controller's thermostat. I will install a normally on relay powered by the eco pump supply to control the booster pump that will ensure both pumps are never on at the same time. Thanks in advance for any input. Re: Pool heating 2Sep 13, 2015 11:12 am Where are you located? How long do toy want to swim for? Recently moved to a 60's home in need of some improvement! http://s797.photobucket.com/user/leenii ... ch%20House Old house: http://s797.photobucket.com/albums/yy25 ... loo/House/ Re: Pool heating 3Sep 13, 2015 12:39 pm What size & type of pool is it ? Do you want to use it may - September ? Do you want it heated ready for use all the time or probably just weekends ? How quick do you want it to warm up ? What temp do you want it ? As a general rule the more you spend up front the less it costs to run . I wouldn't go near rubber mat solar unless you like climbing on the roof repairing leaks . Re: Pool heating 4Sep 13, 2015 12:45 pm leni Where are you located? How long do toy want to swim for? Thanks leni I'm South East Queensland and are probably looking to extend my season by two months either side of summer although my intention is not really what's specifically best for me but rather more generic information. There is of cause a lot of factors to consider for individual needs; construction type, pool shape, wall colour, exposure, shading, surface area and volume. A good 'rule of thumb' is to provide the pool surface area in roof top matting or collector where slightly less is needed for panels and even less for glazed panels. And maybe slightly more area of roof top collectors in the southern states. Its probably worth adding that north facing roof space is best, west is probably better than east and south is a bit useless. It may also be worthwhile to add a little bit about plumbing. Long sweeping bends or two 45's in place of one 90 deg elbow will produce less head loss but most pool pumps are high pressure high flow where the pump is slightly over sized and any slight differences in head loss wont matter. The eco pumps are low pressure high flow where head loss can make a difference. Assuming most solar booster pumps have 50mm inlets and outlets its best to go up to the roof in 50mm pipe and come back down in 40mm but thats probably more important for double story applications. For DIY collectors water goes in at the bottom of the collector, out at the top with the pressure relief valve at the absolute top before the plumbing heads down. For flat roofs the return plumbing should be raised a little above the collector with a series of elbows. I guess the best advise would be to follow the manufacturers instructions very carfully. Re: Pool heating 5Sep 13, 2015 12:58 pm wheeliworks What size & type of pool is it ? Do you want to use it may - September ? Do you want it heated ready for use all the time or probably just weekends ? How quick do you want it to warm up ? What temp do you want it ? As a general rule the more you spend up front the less it costs to run . I wouldn't go near rubber mat solar unless you like climbing on the roof repairing leaks . Thanks Wheeliworks, I was looking at some of your pool pics last night and they look great. We have a concrete pool, 40,000L and ~40sqm, facing east in front of a two storey building. I think 28 degrees would be good for us, set and forget. We only really achieve 28 degrees towards the end of summer. I've heard stories about the rubber mat solar and I'm not selecting that due to my metal roof and box gutters but having said that we can see the neighbours roof and rubber matting which has been there trouble free for many years now. Re: Pool heating 6Sep 13, 2015 1:21 pm I'm in Perth and will go for solar rubber tubing style. I'm a tight ***! Recently moved to a 60's home in need of some improvement! http://s797.photobucket.com/user/leenii ... ch%20House Old house: http://s797.photobucket.com/albums/yy25 ... loo/House/ Re: Pool heating 7Sep 13, 2015 1:42 pm From the info you supplied I would go with a pvc panel solar system . The theory I use is to put as many sq m on the roof as possible . The benefits are it will extend season at both ends & is cheaper to run as it will reach your desired temperature earlier then pump will be off . I used the glass panels with rubber tube years ago . It was a major fail . On a 45deg summer day all the rubber melted . I had to replace with moulded pvc ones. The fact they still sell them must mean this is no longer a problem but I would never use them again. As for general info . If pool is under 20000 litres I generally recommend gas . The advantage is it can heat a pool in a short period of time . I generally spec it to heat pool to 30 deg in middle of winter in 4 hrs Autum / spring in 2 hrs . The bigger the heater the more it costs up front but the lower running cost . A classic example is a customer with a 9000 litre pool wanted instant heat . We fitted a 450mj gas heater . In doing so we needed to fit a new meter & bigger gas pipes . The end result was pool. Heated from 17-32deg in 20 minutes . The cost to heat is minimal . If you plan to use pool every day a heat pump will work out the most efficient . It will work a lot better with a blanket but if aesthetics is important a blanket is ugly. When buying a heat pump the sizing manufactures recommend is about half the size you really need . The other problem in comparing a heat pump is they aren't uniformly rated .a 5 kW in one brand can be the same as a 13kw in another brand . They rate output at ambient temperature . A heater rated at 5kw at 6deg could be sold as a 13kw at 35deg. . If your in a cold climate you need one rated to work at under 12deg . A lot don't . You also need one with a auto defrost . When. Choosing a heating system the questions are 1-when do you want to use it 2- do I have natural gas ( is it a option) 3- do you want to spend more upfront or ongoing ( another part to this is how's long you plan living there for . If selling in a few years efficient heating won't add value to property) 4- do I want instant heat Re: Pool heating 8Sep 13, 2015 1:53 pm leni I'm in Perth and will go for solar rubber tubing style. I'm a tight ***! The rubber matt is fine if 1- there area no cockatoos around 2- no trees which can drop sticks on it 3 - no strong wind to blow it off the roof 4- no hail storms 5 -you don't mind regularly climbing on the roof with a knife & joiners 6 - your roof isn't visible from the ground Otherwise the panel systems generally have a 20 year warranty , and are about 20% more efficient . They do cost about 20- 30%'more but well,worth it Cheers Re: Pool heating 9Sep 13, 2015 2:26 pm Thanks wheeliworks, Some really good info, a lot to think about. I'm thinking of the polypropylene panels from either Zane or Heliocol, Heliocol also make the sunX which I guess is kind of semi glazed but these need to drain out so no good for me. The OKU look OK but I'm worried about all those extra hose connections. If I didn't have a flat metal roof with box gutters I would seriously consider the rubber mat. I'm a bit of a tight ***! too, we all like to save a few $$ ah. I think the ruber mat maybe best suited to tiles, replacing a bit of gutter isn't too hard if it does leak. Re: Pool heating 10Sep 13, 2015 3:02 pm I think on those criteria we will actually be OK! Will consider the panels too! Recently moved to a 60's home in need of some improvement! http://s797.photobucket.com/user/leenii ... ch%20House Old house: http://s797.photobucket.com/albums/yy25 ... loo/House/ Re: Pool heating 11Sep 13, 2015 3:29 pm i bought a house that has an inground concrete pool that has the black mats on roof they actually have multiple 6mm pipes running through them my system uses 40mm pressure pipe from pool to pump then roof and return this is about 15 years old previous owners had not used for several years found a few of the 6mm pipes leaking due to the number of pipes i simply tied a knot in any leaking tubes this is seperately plumbed with its own pump added a cheap solar controller aquasun 3 definitely extended the season and reasonably cheap to run Does anyone have a suggestion for a good hydronic in slab heating speacialist who may be able to help me with an existing system and wether or not it may need a seperator… 0 4963 Hi everyone, Looking for some advise. 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