Creating a solar thermal heat dump?

flopstocks

Hello Dad and I completed a solar thermal install on my property last year and it has been working very well. I had a few joints that were seeping slightly so decided to drain the system to fix them. Once drained the glycol it has gone a brown/black colour caused from overheating I assume. I'm using a 30 tube collector with a 200 litre tank, I wish I purchased the 300 litre tank now.

So I believe I need to setup a heat dump to prevent the glycol overheating in the summer. I am thinking about putting a radiator in the airing cupboard, and diverting the flow to this when the temperature reaches say 65 degrees. I have found something called a Solar transfer valve.

http://www.rmc.com.au/files/spec_sheets/MIX11091_3.pdf

My plan is to run this slightly different that what it's designed for (heat recovery). I connect the output when temperature is hot to the airing cupboard, and when cooler the system just runs as normal. Is this a viable opption?

Thanks in advance

reeac

flopstocks wrote: »

Hello Dad and I completed a solar thermal install on my property last year and it has been working very well. I had a few joints that were seeping slightly so decided to drain the system to fix them. Once drained the glycol it has gone a brown/black colour caused from overheating I assume. I'm using a 30 tube collector with a 200 litre tank, I wish I purchased the 300 litre tank now.

So I believe I need to setup a heat dump to prevent the glycol overheating in the summer. I am thinking about putting a radiator in the airing cupboard, and diverting the flow to this when the temperature reaches say 65 degrees. I have found something called a Solar transfer valve.

http://www.rmc.com.au/files/spec_sheets/MIX11091_3.pdf

My plan is to run this slightly different that what it's designed for (heat recovery). I connect the output when temperature is hot to the airing cupboard, and when cooler the system just runs as normal. Is this a viable opption?

Thanks in advance

You mention glycol so is it actually vehicle antifreeze? If so then it will withstand over 100C and last for years. Maybe you're worrying too much about the discolouration. Perhaps it's picked up dirt from the inside of the pipework.

flopstocks

I had the proper solar glycol installed. But left the system shut down and partially filled on Thursday and Friday due to having to work. After research I believe this could have been my problem.

Yesterday I had a cold tank of water, and the solar raised it to 55C, and this was not a particularly warm day. My worry is that if we are not using the water in the summer, if on holiday say. The temperature of the pannel will rocket, I would be more comfortable if I had a heat dump feeding my airing cupboard, consuming the extra heat.