DIY garden hose pool solar heater problems

[Charlie_R]

You could keep the 1000 gph pump, but going to a better pump would give you a bit more head to work with. Also, that would change from a draw-through/suction filter to a pressure filter, which works much better. The added flow/pressure from the better pump coupled with multiple paths in your solar collectors will do a much better job of heating the water.

When I suggested the manifolds, I meant that you could cut the hoses in the collector and add new ends to the shorter pieces of hose. This would be a good off season project for you.

One thing though, if you go with a better, higher flow pump, you'll have to get the proper pool wall fittings to match. I would suggest not cutting out the old hose fittings, but rather adding the new fittings in new holes. That way you can still use the old for other purposes later.

 

[mas985]

My question would be. Even if the head loss increased do to the two pumps still sharing the same collector pipes, would there not still be more velocity creating a higher flow rate? Please remember this is all new to me.

Two pumps in series can provide more head gain which in turn can increase flow rates. Pumps have head gain or add head, plumbing reduces head or loses head. The Hydraulics 101 sticky in my signature goes over some of these concepts.

Also, here is a good reference:

http://www.engineeringtoolbox.com/pumps-parallel-serial-d_636.html

 

[Glasgowspeaker]

Charlie_R -

I think what I am going to try is to use the manifold suggestion to reduce the head loss and keep the same pump. If I find that my flow rate is still to weak, due to still having too much head loss, I will add a second pump. Whether to use in series to increase the head, or in parallel to increase the flow, I guess i'll cross that bridge if I have too? But I'm thinking series because head loss is definitely a problem and running is series seems easier.
Thank you for all of you help.

mas985 -
Thank you, I get the general concept, It sheds a bit of light on the subject

Thank you to all that have replied. Once I have completed the alterations, I will post again to fill you in.

 

[CeeElGee]

CeeElGee -

But if I'm reading you correctly, the jist of what you are getting at is to leave the pump alone. Change the feed to 1 1/4" in parallel "T"d to both collectors. and then again with another 1 1/4" "T"d for both returns.

Thank you once again.

Tom

Yes, at the very least, begin by reworking your runs to and from the collectors with 1-1/4" hoses. Put a T at the end of the hose feeding the two coils and branch off to both with some sort of bushings or reducers. Then reverse the process coming back. That will increase flow and run the two in parallel.

I don't like those splitters someone else linked to (I wouldn't even call them manifolds) because you still are restricting flow down to a single 3/4" connection before splitting it. Those are fine for a water system with 50-60 psi but not applicable here. A true manifold such as on a commercial solar panel has a 1-1/2" tube evenly distributing water to dozens of pencil-thin tubes. I have found it's a fine balance between pressure and flow to get the maximum efficiency out of one of these systems.

As for my 635T, no, I'm not recommending that you buy another one. I thought you had said you had one or something similar to it to add to your small pump. If you're going to spend another dime on a pump, go bigger than that. I actually am looking at that 3/4-horse pump you found on eBay for my system next year -- with perhaps another 2'x20' panel.

Lastly, my comment about the sump pump hoses and pressure vs. suction, this is all on the pressure side, so no need to worry about that. Only suction is between the pool and the pump.

 

[mrmacdad12]

You are heading in the right direction. I currently use the 1000gph pump solely for my solar. I run it filterless as I use the upgraded intex sand filter for my primary filtering. I couldnt imagine using that small pump to do both jobs. Maybe get another small pump since they can be had very cheap and run a stand alone solar pump. I have mine plumbed into the existing pool drain ( the one at the very bottom of the wall ) next year ill have 2 more coils so a total of 3. I used 1inch pvc for the manifold out of the pump it goes into a T fitting then 2 90s each side with a ball valve. One end is to solar coil. Other end non heated pool return so I can adjust flow without backpressure on pump. Works good. Just need more coils. Also planning on making a barrel stove and running 3 parallel copper coils so I can add heat when the weather doesnt play nice.