Open vs. Closed Loop

[BParson03]

I was wondering which one is better. It seems to me that the open loop uses a lot of water, but they also seem to be more common than the closed loop systems.

[bigwheelingman]

closed loop is better.There is no chemical feed required like a open loop

[tampajack]

Open Loop means that you pull water in (you could also use an "injection" well and put the hot water back in). With the injection well, you don't "use" any water. You pull it out when it's cold, put it back as hot water.

[dorff]

Open loop, check the BTU charts for your entering water temperature for your climate. I prefer closed though, less maintenance over open loops.

[lemagr67]

We always put in closed loops. The biggest reason for that is we know what is in the loop and it's not going to change. When you have an open loop, you have a potential to introduce things into the system that you didn't account for. Granted, alot of the time nothing bad happens, but we prefer to play it safe and only have what we put into the flow center entering the unit. I do remember reading that open loop systems tend to be more efficient though.

[energy_freak]

We always put in closed loops. The biggest reason for that is we know what is in the loop and it's not going to change.

And how do you figure out temp change in your heat sink (earth, in your case). Let's assume summer (A/C cycle) in hot humid climate. Did you run calculations of projected temperature rise in surrounding earth due to constant heat transfer? Did you also calculate an impact on unit efficiency based on a increased earth temperature? Or you decided not to bother yourself with these "nuisance questions and details"

[texas cooler]

We install closed loop due to water pumping power requirements with a deep water table.

[energy_freak]

We install closed loop due to water pumping power requirements with a deep water table.

No doubts, the safest approach among all of them (though, not necessarily the most energy efficient one, but who is measuring...).

Though, as I said earlier, there are many variants in a closed loop design, strategies and implementation and I am not sure if anybody provides homeowner with comparative costs vs. projected future performance.

If I was to install the system myself and I am seriously considering it I would require performance bond guarantee / contract from the installer, ABSOLUTELY NOTHING LESS. There are too many of them who have NO CLUE WHATSOEVER!! There is a decent majority out there who do it because that is the only way they can make a buck!

[rcameron]

depending on the climate and the water temeperature open loops are more efficient but you also have to count the energy the well pump is consuming. if you run out of water or you well pump fails then you have no heat or cooling. it is cheaper to use an open well obviously. loop temperatures in the winter ususally drop to about 30 degress f and well waters is around 45-47 degrees f.