Water to Air heat exchanger?

[NCFord]

Would a Water to Air heat exchanger ever work in place of a copper coil to heat water storage?
I have a friend who is convinced it will but I don't think it will work. My boiler is only going to "charge"
my water stoage, I then have an open loop that will supply the house with heat and DHW. The advantage of the Water to Air H.E. would simply be the cost. I large H.E is only about $200. Since I have the open loop to the house I could even direct the return water past the exchanger. I know that
for a water to water exchanger to work it's all about surface area, and with a Water to Air H.E. there will be less copper, but the alum. fins would help, I guess. I don't know about this idea, but it might be worth talking about?

 

[arngnick]

I say yes but I would oversize it and since there are many joints in these hx they may be prone to fail compared to a solid copper line. I have seen people use pex for hx if that may be an option. I am also on the edge for which direction to go when I add a solar loop to my system...just my two cents

 

[NCFord]

Thanks, that's more positive than I expected. There are lost of joints but they used all the time and
don't really leak. I always pressure test just to be sure though.