Jeff OH,

No diagrams yet... Ony bids and basic specs. I hope to start construction this March/April. Will gladly post diagrams if/when I get them.

Jeff

It's been awhile since I've been here: maybe a couple of years and the format seems a little different.

Anyway, as to storage and cycling, I may have something that might work although, I must say, it might be too large for the average domestic installation. An engineer might have fun doing the calcs and trying to see if a system is feasible

In my back yard, I have 28 "ice banks" that I removed from the Dartmouth/Hitchcock Hospital in Hanover, NH. These are 2000 gallon heat exchangers that make ice during off-peak hours to suppliment the air conditioning load during the day. There are four manifolds (two circuits) and a total of 56 loops @ 235' each. The heads and tank wall are HDPE. The coils are clear polyethelene but I haven't determined if they are PEX. The units are insulated with 2" of EPS board which is held in place with a wraparound aluminum skin. The coils are arranged in a counterflow configuation. This means an adjacent tube is in proximity to the other circuit. They are made by Calmac. They weigh 1500 lbs empty. Height is 102" x 89" dia. Shipping height is 96". The hospital renegotiated its utility contract and no longer needed the off-peak capacity.

It seems to me that one circuit could deliver fossil fuel and/or solar heated water/gycol and the other circuit would supply the heating medium for the living space. There is also room at the center of the coils for a DHW coil for preheat or direct use.

I think we can all agree that short cycling would not be a factor with this setup. If you want storage, all 28 tanks are available. These tanks were designed for outdoor or inside use.

Any pics of these available?

Maybe?

I have alot more pictures and can take more if necessary. I actually have 29 tanks but I disassembled one for photos and to see how they are made .

The only caveat I have about using the ice banks for heated water is the loss of tensile strenght of the high density polyethelene tank wall. I think it will be adequate to 115 degrees. Above that, I might add a 16 gage steel wrapper next to the tank wall around the lower 2/3rds of the tank. A plastics engineer should be able to specify the alteration.

The following link is a page from the Calmac website that describes the "ice bank".
ice bank