Tank liner-storage medium

[NHFarmer]

I have a homemade circular storage tank similar to an above ground pool, I originally installed an EPDM liner and built a fairly substantial cover for the tank. The liner lasted 8 years with a max temp of 170*, no complaints at all with the life of the liner. I am really not looking forward to changing the liner and I am weighing my options. I contemplated using a liner from AST but I really don't want to spend the money. So has anyone had any experience with any other liners or coatings? Another crazy idea is trying a stop leak product or perhaps a gel material that won't leak from my existing liner. Another crazy idea is to replace the water with sand as a storage media. I realize that replacing the liner with either EPDM or ideally an AST liner is probably my best bet but I am interested to hear if anyone has had any success with any other storage options

 

[stee6043]

I'm interested to hear about the sand idea. How would you transfer the heat to/from the sand?

 

[NHFarmer]

I have home made copper coils and the thought was to simply fill the tank with sand the same as I currently do for water only no leaks. My research says that the sand is great at holding the heat but not so good at exchanging back to the heating system. I am just looking to see if anyone has tried this or any other ideas

 

[maple1]

Sand would seem like a big non-starter to me.

Can you get and do another EPDM? 8 years seems decent to me. Have you gotten an accurate estimate on an AST liner? Sometimes you get what you pay for and I am also thinking if someone found a better mouse trap we would have heard about it by now.

 

[NHFarmer]

Maple1, I can and probably will get a replacement EPDM and yes I did get a quote from Tom, The price actually seemed very reasonable and in reality is my best bet. At the moment I just don't have that much money to spend. I agree with the better mouse trap but was just checking around to see if I had missed any new ideas, sure looks like I haven't

 

[tom in maine]

If you go with EPDM, it will last longer at 160F or lower. You also need to check pH regularly. Keep it slightly basic.
Sand has 1/5 the heat capacity of water. As do most materials other than water. Water is a cheap date, with some limitations (like it has to stay in a tank!)
If we can help, let us know.

 

[NHFarmer]

I have cast iron radiators so I can go with slightly lower temperatures besides my heat exchanger will only allow about 170* max so the 160 range is pretty common for me. Tom, I would love to go with one of your liners but it is just not in the budget at the moment. Looks like I will have to settle for water and an EPDM liner, worked well so far