Well, that was cheaper and quicker than the PV. Took them seven hours to install the entire system. We have two Wagner collectors, Â one 92.5 gallon storage tank, in a drain back arrangement (it’s basically this Secusol system), with our super-efficient oil boiler as backup (second heat-exchanger). A fun addition was the monitoring system, which the State of Massachusetts paid for. We’ll have data soon! We like data.