Got a sadia swebline hot water tank that I think used to contain an immersion heater but now has some form of coil inserted via the immersion heater boss 
. Used to heat the 50 gal tank ok but slowly. Now doesnt really even though pipes in and out are hot - we are in hard water area and assume external surface of coil is scaled up ( even though Fernox "bag in the tank" limescale preventer fitted in DHW header tank) . Any idea where I can get replacement coils such at these ?
Thanks for reading
Trevor
. Used to heat the 50 gal tank ok but slowly. Now doesnt really even though pipes in and out are hot - we are in hard water area and assume external surface of coil is scaled up ( even though Fernox "bag in the tank" limescale preventer fitted in DHW header tank) . Any idea where I can get replacement coils such at these ? Thanks for reading
Trevor
