Running lines to baseboard heater using Pex.
something to consider is if their is a headder running several heating loops or elements, they have to be within 10% of each others length, unless a balancing headder is in use. If one loop is significantly shorter than the others, it will get the majority of the flow. Also as Jpelzer said their is a difference in pex types, the heating pex has an oxygen barrier, and it is usually, but not always colored red. The pex for heating will be stamped as such and state,"not for potable water".