Norsun Q-sol series plate collector Internals

[tandrews]

Educational post for those with some of these Canadian made panels.
Photos of the guts of the system. Note heat plate tubes are isolated (I'm not asking) from main trhough pipe flow. Plate tubing contains a volatile fluid to transfer heat to through piping.
An old tube was cut and drained and fluid was not flammable, but smell was not far from acetone.
These old panels can pass a pressure test, but heat tubing may have failed to atmosphere, leaving heat collection a fraction of a output.
Pictures are clickable thumbnails for larger version.

The frames, insulation and backing


The bottom back of plate tubing

main manifold jacketing, and plate tubing fill pipe from back of plates

Back of plate


Now you know.

[dksolar]

Norsun Q-sol collectors

Just wanted to add a footnote re: Norsun panels....the liquid in the collectors is a refrigerant, each collector operated as a self contained "heat exchanger". Solar radiation hitting the panel caused the refrigerant to evaporate, rise in the tubing and transfer its heat to the solar fluid being pumped thru the top manifold. The refrigerant would recondense in the process and then this cycle would continue.

[jfguay2]

How to refurbish; is it worth buying?

Just wanted to add a footnote re: Norsun panels....the liquid in the collectors is a refrigerant, each collector operated as a self contained "heat exchanger". Solar radiation hitting the panel caused the refrigerant to evaporate, rise in the tubing and transfer its heat to the solar fluid being pumped thru the top manifold. The refrigerant would recondense in the process and then this cycle would continue.

Hi there,
I am about to buy three of these old panels for 400$ canadian. Is it worth it, and will I be able to retrofit them so that water can circulate through all risers?

Thank you,

JF

[tandrews]

"Is it worth it"
Depends on you and your skills and budget.

Consider you couldn't replace the glass for that, and yeah, probably worth it.
If you plan to disassemble and restore them, I question why you would wish to run fluid through the entire panel as the design is solid and proven.
There is benefit to isolating the heat loop from the main system.

You may negotiate with the knowledge that they may have already failed in several ways, and you don't wish to play the lottery at 4 bills.
Either way not a bad price if they are intact - but that's a guess.

They can be retrofitted to run fluid through the entire panel, but you do have some work ahead of you to do so.
Pressure test them with your lungs at least, you'll know quickly if the heat exchanger tube on top has failed.
Even if that doesn't matter to you it's a reason for a lower price.
Good luck.

[jfguay2]

"Is it worth it"
Depends on you and your skills and budget.

Consider you couldn't replace the glass for that, and yeah, probably worth it.
If you plan to disassemble and restore them, I question why you would wish to run fluid through the entire panel as the design is solid and proven.
There is benefit to isolating the heat loop from the main system.

You may negotiate with the knowledge that they may have already failed in several ways, and you don't wish to play the lottery at 4 bills.
Either way not a bad price if they are intact - but that's a guess.

They can be retrofitted to run fluid through the entire panel, but you do have some work ahead of you to do so.
Pressure test them with your lungs at least, you'll know quickly if the heat exchanger tube on top has failed.
Even if that doesn't matter to you it's a reason for a lower price.
Good luck.

Is it reasonnable to expect that they are still intact? How about the efficiency, wouldn't it be better if water circulated throught them? If anything, I would rather not have to do anything at all but start using them.

Also, wouldn't you say that even though the heat exchanger still holds pressure, that doesn't mean that the risers are intact right, since they are separated from one another...

I just want to be sure I am not wasting 400$...

Thanks again,

JF

[tandrews]

Is it reasonnable to expect that they are still intact? How about the efficiency, wouldn't it be better if water circulated throught them? If anything, I would rather not have to do anything at all but start using them.
Also, wouldn't you say that even though the heat exchanger still holds pressure, that doesn't mean that the risers are intact right, since they are separated from one another...

It is a gamble without pulling the glass off to have a look at the heat pipe portion up close.
If it were better with water in them, they would likely have been built that way (I understand <rumor> some Norsuns were made that way in a different iteration of the same panels).
I cannot speculate the life these lead, but in my group of six, one had failed internally (between heat exchanger and heat pipes) and one had overpressured the heat pipe portion and melted the glassboard insulation underneath it when it jetted itself empty. The first was discovered pressure testing with PEX caps, tees and jerry rigged hand pump, where it took much more effort to come to same pressure as I was pressurizing the entire piping rather then just the trough tube. The second was visible on inspection - only once the glass was off.

Perhaps your primary consideration is - why are they for sale in the first place?
My price came down when I explained they may be all garbage other then parts.

[jfguay2]

It is a gamble without pulling the glass off to have a look at the heat pipe portion up close.
If it were better with water in them, they would likely have been built that way (I understand <rumor> some Norsuns were made that way in a different iteration of the same panels).
I cannot speculate the life these lead, but in my group of six, one had failed internally (between heat exchanger and heat pipes) and one had overpressured the heat pipe portion and melted the glassboard insulation underneath it when it jetted itself empty. The first was discovered pressure testing with PEX caps, tees and jerry rigged hand pump, where it took much more effort to come to same pressure as I was pressurizing the entire piping rather then just the trough tube. The second was visible on inspection - only once the glass was off.

Perhaps your primary consideration is - why are they for sale in the first place?
My price came down when I explained they may be all garbage other then parts.

Ok, Ipicked them up this week-end. I as told they were still functionnal when they were last used. I tried to take a peak inside one of the panels, and from what I could see, it looked fine. Mind you I did not take it all apart as it seemed difficult to put the glass back.

I did sense that the exit pipes of the header warmed up when the sun was out so I am hopeful. Having said that, can the panels be used with water in a drain back system, or do I have to use glycol since I am in Canada?

[tandrews]

Congrats.
Dissassembly starts with the four glass retainers.
Using a prybar/screwdriver at the widest opening at a corner on top (glass up), pry the top upward, using the outside corner as leverage.
Essentially don't pry against the glass (obvious, but worth saying for all the time it takes).
The glass is held in place by these four strips of angled aluminum (see pix).
They simply snap in place and once a corner has been lifted, it's easy to follow the lift to the other end.

Even failed panels will warm the tubes.
Not a measure of full function.

Suction cups will assist in lifting the glass to get a grip on it.
I used a couple of these to handle it:

http://www.princessauto.com/pal/product/8136616/Dent-Repair-Tools/4-1/2-in.-Suction-Cup

It simply sits in the frame with no press fit, weatherstripping wraps the glass and comes out with it.

Glycol is a good idea, but drainback can make it redundant.

[jfguay2]

Okay then, so essentially, short of opening the panel up, there is no way to tell if it is still working properly? I was thinking that if I hooked up the through tube and circulated cold water, I could quickly tell if cold water also made its way to the heat pipes hence indicating that they failed somewhere in between. Now should they not become cold quickly, that does not mean that the fluid is still in the heat pipes. Talk about a tough way to tell.

Now provided they still work, and since I can't read the labels anymore, what output can be expected by panel on a clear day? 1500 btu/h?

Regards,

JF

[tandrews]

Okay then, so essentially, short of opening the panel up, there is no way to tell if it is still working properly?

It's really not that difficult. Effort well spent before one places them where they will not move for many moons no?
Inspection is the only way to know if they're in good shape. Glass comes out to do that.

I was thinking that if I hooked up the through tube and circulated cold water, I could quickly tell if cold water also made its way to the heat pipes hence indicating that they failed somewhere in between. Now should they not become cold quickly, that does not mean that the fluid is still in the heat pipes. Talk about a tough way to tell.

Even this requires glass out. If there is not cold transfer it still doesn't rule out a heat tubing to atmospheric failure. Eyeball the evidence.

Now provided they still work, and since I can't read the labels anymore, what output can be expected by panel on a clear day? 1500 btu/h?

As you can see from the pix above, the labels don't even suggest output.
I haven't done any research to compare a new 3x6 panel's output.
if you find some relative value, please include it in this thread.

Even if the heat tubing fluid is gone, the through pipe has failed to the heat tubing, they will still make heat.
Better then a kick in the arse with a frozen boot as they say, but worth fixing while you can get at them too.

If however the heat tubing has breeched to the through pipe as one of mine had, and you go drain back rather then glycol, you can expect a leak to the roof on first frost thaw.
That would suck, and ruin your day(s).
I suspect there may be stagnation issues as well if they are not modified properly for flooded glycol only.

One fellow I spoke to converted his for full glycol flow, but ran them upside down to avoid this using the heat pipe common manifold as throughput.
Some modified plumbing required, which becomes obvious when you're staring at it with the glass off.

[jfguay2]

Alright, fair enough. Now since it was sunny this morning, I put one of the panels out in the sun, and measured how warm the exchanger tube gets, without water in, and believe me, it got hot, around 250F. My theory is that if only the exchanger tubing got that warm (I could tell since the glass became extremely hot over the exchanger but not anywhere else on the panel) this would mean that the fluid is still in the heat pipes, and that still transfer to the exchanger given the quick rise in temperature. Had the risers failed, I don't believe that the exchanger could have gotten that hot just by being connected to the risers, and by conductivity of metal... what do you think.

I know I sound like I don't want to open them up, and you are right about that, not if I don't have too.

Also, what is a reasonable tank size for three of these panels, considering that I would want to capture as much heat as possible in the summer, since I am thinking of running an extra loop as a second heat exchanger within the solar tank to run my pool water in, so that I expect the solar system would virtually never stop given the size of my pool.

Is that crazy? I already have a heatpump for the pool, but also want to take advantage of the panels as well in the summer.

JF

[tandrews]

You don't have to open them up, really you don't.
Your call. No pressure.
I didn't want to either until I saw how they can fail.
Even then i was shy about messing with tempered glass in 3x6 format.
I am glad I got over it.

I don't know what angle you had them to do your test.
Heat rises, it doesn't care if it goes through heat pipes or slides up the inside of the glass.
That said, the glass in my good panels didn't get very warm at all while the header pipe did.
The bad panels had hot upper frames and glass.

Tank size is proportional to usage.
Maybe your tank is all pool? All Domestic hot water?

[jfguay2]

You don't have to open them up, really you don't.
Your call. No pressure.
I didn't want to either until I saw how they can fail.
Even then i was shy about messing with tempered glass in 3x6 format.
I am glad I got over it.

I don't know what angle you had them to do your test.
Heat rises, it doesn't care if it goes through heat pipes or slides up the inside of the glass.
That said, the glass in my good panels didn't get very warm at all while the header pipe did.
The bad panels had hot upper frames and glass.

Tank size is proportional to usage.
Maybe your tank is all pool? All Domestic hot water?

I ran cold water, at around 49.6F, and it was coming out steadily at around 53.6F, for a differential of 4F. At a flow rate of around 3.1 gal/minutes, I come up with an average of 5400 Btu/h, which would have to indicate proper output right? While my test was no where near in perfect conditions, this is impressive, and means that since we get around 10 hours of sun, I might get around 162 000 btu per sunny day, hence my question about the size, since I do not want the system to shut down because it reaches 150F in the tank at 1 am, thus loosing on the heat for the rest of the day. I am thinking at least 120 gallons, but again, as I said, I would like to use the solar water tank for heating the pool in the summer, and heating my domestic hot water the rest of the year, so should I go even higher, and get something like 200 gal. I am thinking of builind my own anyway.

JF

[Naptown]

Use a 120 Gallon tank.
If you decide to use excess heat for the pool use a titanium/ pvc heat exchanger or you will be replacing it every couple of years. Copper and pool chemicals do not get along well together.

[MikeSolar]

Rule of thumb for all panels is between 50-100L/m2 of panel area. I know that is a big range but you have less than 2m per panel X 3 so depending on your daily usage an 80 gal tank would be minimum.

I know the Norsun panels, scrapped about 200 of them 15+ years ago, had a lot of glass too. All gone now. Oh well.