Hi heres your dilema, a 45 degree north face would need 8 to 12 panels to achieve a 15 to 20 degree change in tempature.

It depends on what kind of product you decide on my price would be anywhere from $5,500 to $6,800 for plumbing, product and labor.

If it were me, I would go with the hayward HP6002 a much cheaper alternative. With a 5 year warranty.

Just my opinion: But choose what will be best for you.