solar panel fillings

Dave Palmer_3

are most solar panels filled with,gycol? I looked at a job were the folks what to disconnect the solar panels but I have no idea whats in the tank or panels. I don't want to open a can of worms if its toxic,any ideas? thanks Dave

hot_rod

Like a box of chocolates

ya just never know what you'll get.

Various glycols have been spotted in closed loop systems. Hydronic, automotive, RV. All fairly benign, althouhgh I would still capture and dispose of them via recycling centers.

Plenty of heat transfer oil systems out there, also. Nasty stuff to spill and a fluid not to be put down the drain!

Dow has a product called SYLTHERM (sp) that I have come across also. A silicone based product, I believe. Another messy, when spilled, product. Neither are water soluable and easily distinquished from glycols, usually.

The oil based products had a much higher temperature rating and could withstand stagnant conditions much better than glycols which peak out around 325- 350F.

I'd recommend getting some empty 5 gallon buckets and drain and blow out the fluid. See if you have a Safety Kleen branch near you. They will properly handle whatever you may have in there. It's also wise to keep documantation of the disposal transaction, IMO.

hot rod

Dave Palmer_3

Rod

on average what would a small system hold,ballpark? Thanks Dave

hot_rod

Flat plate collectors?

how many? Usually a couple gallons in the panel, piping amount (Siggys Design Studio could calc that) heat exchanger in the tank? A couple gallons, perhaps. Expansion tank? Not much there. Depending on the pipe size and length I'd guess 10- 25 gallons??

I usually drag one of those plastic 55 gallon drums to the job. Much easier than switching the hose from bucket to bucket as the jucies start flowing. Chemical or food processing places usually will give used drums away. I suppose a steel drum would be fine. As long as the system is not filled with acid! Just kidding

Stick the drain hose into the drum, set your toolbox on it so it doesn't pop out, when you're not looking! Then connect your air compressor, with the regulator set below the relief valve setting of the solar loop!, and you should be able to shove all the ?? fluid out into the drum.

Usually the solar loop is piped with isolation and purge valves for ease of fluid installation and removal.

Take a poly tarp, to use as a drop cloth, maybe some floor absorbent, wear safety glasses! and make sure all the women and children are out of the building

hot rod

Dave Palmer_3

thanks

that what I needed to know , Dave

Joe_10

draining solar

Most Grumman units in this area that haven't been serviced in the last ten years still have the original quick connect charge ports. They can be drained through the pressure relief valve. In New Mexico there is a market for used systems.

Ron Huber

Ethelyne glycol

Was used in Grumman systems because it had a double wall heat exchanger. The etheleyne glycol can last longer in a closed loop solar system than propeleyne glycol. The hydraulic fittings can be replaced by 1/2" boiler drains. These systems outperformed the systems that have in tank heat exchangers.

hot_rod

I've seen

some with a fluid that looks, smells, and feels a lot like ATF, in solar systems. Maybe it was! There are many, many heat transfer fluids out there, lots oil based.

Potassium acetate (sp) was another, popular in the PB days. Used to be sold by Vanguard, I believe.

As Ron mentioned, ethylene glycol is a better heat transfer fluid than propylene. It will run up to 350F and is pumpable down to - 60F! Less viscous. But you have to be aware of the increases toxicity.

Ethylene is not a good product for ground source, or potable water exchangers, government regs may prohibit EG use, in this case, in some states.

Unless someone labeled the system, or left an empty container, no telling what you may find lurking in dem ole pipes

hot rod