On Thu, 05 Mar 2015 04:06:26 -0500, "Mr. Luddite"
wrote:

We use it from late June, early July to raise the temp up to about 82-84
degrees and from there the water will stay fairly warm throughout
the summer. We also use it to extend the season a bit but don't run it
that much. It's a 150K BTU unit and it's not exactly cheap to run but
is still less expensive than propane.

===

We have a similar unit. I figure that it costs around $5/day this
time of year to keep water temp in the upper 80s. I'll probably turn
it back on in another week or two since I enjoy a daily dip late in
the late afternoon.