diff --git a/nerdamer.core.js b/nerdamer.core.js
index <HASH>..<HASH> 100644
--- a/nerdamer.core.js
+++ b/nerdamer.core.js
@@ -2066,7 +2066,7 @@ var nerdamer = (function() {
                             symbol1.convert(PL);
                             symbol1.attach(symbol2);
                         }
-                        else if(symbol1.power === 1) {
+                        else if(symbol1.power === 1 && symbol2.power === 1) {
                             //since we swap the symbols to place the lower power symbol on the left we only have to check a
                             if(symbol2.power === 1) { 
                                 var s;
Bug fix for addition of CPs

If two symbols are of group CP were being added the assumption was incorrectly made that the left hand side would be the lower power. Now both symbols are checked to make sure that they are both indeed linear.