home made pool heater

jjboods · Postby **jjboods** » Thu 26 Aug, 2010 10:44

I did some research. Fafco uses 1/4 pipes in their collectors. Isn't that a large strain on a pump and not as efficient for heating than larger diameter? I know the water is in the pipe longer, but you get lower turnover.

duraleigh · Postby **duraleigh** » Thu 26 Aug, 2010 11:39

The 1/4 inch "pipes" they use are spaced about every 1/2" so a 4' wide section will contain somewhere around 96 or so "pipes". The water from the manifold does not go up and down through one pipe at a time but, rather is fed simultaneously into all the "pipes" from the bottom manifold or larger pipe.

As 4' sections are added, the water still flows simultaneously through all the "pipes".

jjboods · Postby **jjboods** » Thu 26 Aug, 2010 13:38

The site I saw claims they have 200 1/4 pipes. If I do the math....a 4' section can fit 192 snuggly. So the site was probably rounding up.

That is the same setup I am considering. Indivudually plumbed/connected 8' lengths...water going through them all simultaneously.

Would I still need 1.5" pipe or would my pump not be able to produce the volume for the system?

And would that setup eliminate the significant increase in PSI at the filter?

duraleigh · Postby **duraleigh** » Thu 26 Aug, 2010 14:29

Would I still need 1.5" pipe or would my pump not be able to produce the volume for the system?

And would that setup eliminate the significant increase in PSI at the filter?

Both questions are related to resistence. The 1.5" pipe has far less resistance than the 1" and will allow for more flow and less psi.

The more the water comes in contact with any pipe, the greater the resistance. You will have a lot of water in contact with all those tiny pipes so that increases resistance and reduces flow.

The pump has plenty of power to produce adequate volume through the system. Nevertheless, you will have an increase in psi because of the resistance from all the extra pipe surface.

jjboods · Postby **jjboods** » Thu 26 Aug, 2010 14:39

Either way, I have to think I'd get better flow and less impact on PSI than the Fafco setup.

Correct?

duraleigh · Postby **duraleigh** » Thu 26 Aug, 2010 23:06

Correct?

I don't know. I do suspect it will be very difficult to produce something as efficient as Fafco or other solar providers make......just a guess.

jjboods · Postby **jjboods** » Fri 27 Aug, 2010 07:39

I'm not necessarily comparing heating efficiency. But based on pure physics/flow dynamics, shouldn't a similarly sized panel with large tubes/pipes increase flow and reduce PSI?

jjboods · Postby **jjboods** » Thu 09 Sep, 2010 09:17

I have been looking at Fafco's Sungrabber. Is there any reason to pay $25 for their add on kit when I can buy 2 fernco couplers at home depot for $8?

duraleigh · Postby **duraleigh** » Thu 09 Sep, 2010 09:55

I have no idea but perhaps Fafco could provide some reasons why theirs is better. When I was persuing this a year ago, I found them to be quite helpful.

lbridges · Postby **lbridges** » Thu 09 Sep, 2010 13:50

jjboods wrote:I'm not necessarily comparing heating efficiency. But based on pure physics/flow dynamics, shouldn't a similarly sized panel with large tubes/pipes increase flow and reduce PSI?

As a physicist, I respond yes, but...

For heating you should be more concerned about heat transfer efficiency than flow. Pushing 10gpm through the typical 4X12 foot, in-ground pool style FAFCO panel is less heat efficient than pushing 5GPM through the same panel.

bodypuncher · Postby **bodypuncher** » Mon 13 Sep, 2010 10:13

My FAFCO is a few seasons old and springs leaks way too easily. I suppose if you roof mount it and leave it there it is OK. At the end of each season, unrolling and rolling it, and handling it to store it, puts dents, nicks etc on it. A few times it has sprung leaks. It is large and clumsy to roll up again and put the belt around it for carrying and storing. I barely brushed against a golf ball size rock hidding in the grass and it leaked. I'm about ready to "retire" it and go with a home made black hose model.

FAFCO's design works very well, despite the durability issues. It works without need to accommodate pressure/flow. I think they do that by calculating the flow area of the little pipes to, cumulatively, match the regular inlet and outlet of the pump and pool. I've seen some DIY'ers branch off into larger flow areas and this, of course, drops pressure. So I think trying to keep the flow area the same (reduce diameters when branching into parallel lines) is the key.

Guest · Postby **Guest** » Sat 19 Feb, 2011 09:42

colin wrote:Can anyone give suggestions to a home made pool heater using black pipe on a roof. What size pipe should I use to maintain proper pressure and not to over work my pump? Any suggestions would be great

Thanks

Guest · Postby **Guest** » Thu 09 Jun, 2011 15:54

Can those of you who ordered tell me what pump you ordered from HARBOR FREIGHT? Thanks!

thepoolzone · Postby **thepoolzone** » Wed 15 Jun, 2011 23:02

I have some experience with the solar panels that are sold in the market. They are polypropelene and they have a system of 1 1/2" diameter tubes on them. Some models have baffles in them that obstructs the water from going through the network of tubes too easily. On the top and bottom, there is a header tube which feeds the water to the smaller tubes. You lay the "panel" consisting of approx 36 rows of tubes out in the son on a flat surface such as the ground and then put your return pool line on the outlet side of the "header tube" and then connect the output of your filter to go to the input Header tube. They sell a very simple diverter valve that you put in between the panel and the pool pump so you may close it on a coudy day for instance and divert the water from the filter to the pool, by passing the panel.

They can raise the temp of your pool about 10 degrees so it's worth it!

Good luck!

Jd · Postby Jd » Wed 29 Jun, 2011 16:15

Question: Looking to build my own solar heater on my garage roof (above my 20x40 pool 1.5hp pump).

I was initially thinking using long PVC pipes run back and forth (black ones or white ones painted flat black). But seeing that most seem to mention coils, not sure which would be better. Someone mentioned in a reply back a few pages that PVC would be better so I can only assume PVC would be in straight sections.

Also since my current piping is 1.5", I am assuming I want to stay close to that so either 1.5" or 1" (tee'd)?

I'm north (boston) and want to get the most out of the roof area. I also figure the straight pipes would be easier to drain, but not sure if the turns at each end would put more pressure on the pump.

I am thinking using flex hose at the ends and rather than a quick turn have it go every other row. So the water would feed into top row, then skip down a two rows because of bend in pipe, then down two more rows, and so forth. Then the other "T" would do the same but starting on the skipped row. This would make the bend in the turns less severe hopefully putting less pressure on the pump. This would fill in the whole section of the roof using as much space as possible.

Thoughts?