Removing portion of solar heating system

[portero23]

Hey all -- I'm a long time lurker and first time poster. I've got a ~27,000 gallon ~690 square foot pool with a Heliocol rooftop solar thermal system to heat it as needed. I'm installing a solar PV electrical system to power the house, and to make room for the PV system, I will need to remove 7 of the 15 thermal solar panels.

I'd have 8 panels remaining -- 6 of them 12.5 x 4 ft panels, 2 of them 10 x 4 ft panels, total square footage of ~376 sq ft remaining (726 prior to panel removal).

Do I need to change any pump settings? Just concerned about removing almost 50% of the cross sectional flow through the system might bog down the pump or cause some kind of irreparable harm.


Thanks in advance

 

[borjis]

I'm no export but would think removing panels if anything would reduce any potential issue for the pump. Since it has less area to push the water through.

 

[portero23]

It's actually the opposite. Less cross sectional area means more resistance to flow. More cross sectional area means less resistance. Just wondering if this is an issue if I still have 8 panels to flow through.

Another question I have is if it's ok to have panels on multiple different roof levels. Currently all panels are on the 2nd floor roof. However, I am thinking about moving some of the 2nd floor east facing panels to a first floor roof that is actually north facing. It's that a major issue?

 

[1poolman1]

It's actually the opposite. Less cross sectional area means more resistance to flow. More cross sectional area means less resistance. Just wondering if this is an issue if I still have 8 panels to flow through.

Another question I have is if it's ok to have panels on multiple different roof levels. Currently all panels are on the 2nd floor roof. However, I am thinking about moving some of the 2nd floor east facing panels to a first floor roof that is actually north facing. It's that a major issue?

Eight Heliocol panels should pose no problem depending on the size pump you have. If it is a single speed, you can always adjust the solar valve so that some water bypasses the solar. Heliocol says the optimum flow rate for you panels is 4-5gpm per panel. If you have a VSP (you should in PG&E country, it will pay for itself) you just adjust the pump speed.

You, obviously, won't get the heat into the water as you once did with less panels. You're losing about 45,000btu per day per panel removed.

This site has good information. Ron (of Solaron) has been around a long time, very knowledgeable on the subject of pool solar.

Troubleshooting Your Heliocol Solar Panel System | Sacramento's Solaron | Solaron

solaron.net