Board Thread:Questions and Answers/@comment-74.190.39.37-20121219020522/@comment-24.18.8.160-20121228040342

If the above suggestions do not work, you might be using an outdated version of tekkit, requiring you to make a mark2 geothermal for it to accept piped lava.

In the meantime, power the pump with a redstone engine-considering how long units of lava last, just one should be enough.

Eventually, you'll want switch to using redpower's pump for the larger area of effect.