... 4.It works even freezing -36 split solar boiler Technical Parameters Heat Pipe Solar Collector Spec.(mm) ... , Electric heater, E-Parts box, thermostat, Switch, Anode magnesium bar, T/P valve, Relief valve, dustproof ... or with other heating devices such as gas boiler to assist solar water heating in bad weather ... as to ensure a continous hot water supply2) Anode magnesium Bar: soften hard water in system ...