Protecting my EPDM liner

When I bought my setup (tarm solo plus 60 and 957 gallon STSS unpressurized storage) I was told I could keep the storage at 180F with no problems. Now a few years later I'm hearing 170F, and checking with Tarm they now say 175F.

Anyhow, I want a saftey so I don't overheat my liner and I can still throw a couple extra chunks on at night or before work without worrying about it, My Tarm circulator is operated by an aquastat on the boiler and I can't disable that or I would lose my boiler overheat protection. So here's what I'm thinking:

I could simply add a couple 3P relays http://www.grainger.com/Grainger/items/1A488 (I know I don't need DP) and a close on rise aquastat sensing the top of my storage. each relay wired in parallel with the thermostats could handle 3 zones so it could quickly dump a few degrees of heat and shut off, keeping my storage in the 175F "zone".

Any thoughts or different ideas to accomplish this would be great.

Jack

flyingcow said:

I talked to the STSS guy a few weeks ago and he talked about keeping the tank at 170. It would last longer that way. He thought if kept at 170 it will last 25 yrs +, if kept at 180 might fail alot sooner.

Click to expand...

I had heard 170 and that's what got me concerned when I passed it.

My boiler is about 60 feet away in my shop and my storage is in the basement.

With what I mentioned above I wouldn't have to watch the tank temp so much, and wouldn't have a small amount of wood sitting in the boiler idling away up the chimney.

Burn it hot and efficiently, satisfy the storage, dump the small amount of heat left in the boiler into the house(raising the house 1 or 2 degrees), boiler and circulator in the shop get cold enough to shut off and are not left idling.

If I had storage without a liner I wouldn't be concerned about my storage temps.