does any one know if you can install a second cirk. pump on a system or would the non working one restrict the flow of the second, ime installing a backboiler woodburner and dont want to mess with the original system ,the second pump would be close to the burner with a remote stat so the pump kicks in at say 45degrees and once the system has lost heat turn its self off again, without afecting the old system therefore i can still use the gas boiler if i run low on solid fuel. cheers lee

lee jcb mecanic, July 2010

if you want to use a second heat source to heat an existing system then you'd be better to use the original pump and add on some controls to allow you to control them separately i.e. multi channel programmer, motorised valve, thermostats and an bypass circuit or heat dump so the wood burner won't overheat the system if left unattended.

Ian, July 2010