Hedgepig

Help, please! I have aquired a Showermate single impeller pump which I intend fitting to the hot water feed to the kitchen sink. (We are in a bungalow, so the pressure to the hot tap is very poor). I have just read the blurb on the pump website and it says not recommended for use if: "Supply of pumped hot water service to a common mixer valve where the cold supply is mains fed." Can I get around this problem by fitting a non-return valve just after the pump and before the sink mixer tap? I'm presuming there's a danger of the cold pressure forcing it's way back down the hot feed/pump?? Any adv