Heat tape questions

[upfront]

I have an issue with the main water going into a mobil home.

The main water comes out of the ground to a valve. From the main valve it has Pex running about 12 feet to the utility room. This is 3/4 pex with a splice half way down. I have the senser taped to the pex pipe and the heat tape atached every 6 inch for the full length. The full length as well as the valve is well isulated. I can feel the ice block in the pex line when i flex it, but the heat tape dosnt kick in. The pex dosn't really feel that cold to the touch, but I know there is ice in it. Buy th way the ice block is right at the splice.

First , will the heat tape be able to properly read the temp of the water through the Pex?

Second should I replace the entire Pex line to get rid of the splice ?

Third, if I am replacing the Pex should I use copper instead ? The only issue I have with the copper is that it could split if it frezzes next year, the pex seems to be albe to take the freezing a bit better than copper.

[HayZee518]

the PEX should be one complete length with no splices. reason being that, if it were one complete length, the internal temperature would be the same throughout. a splice would be a different temperature at THAT point. For a heat tape to be installed, wrap the entire length of PEX with a foil tape, then install the heat trace along the bottom of the PEX. Heat rises. Wrap the PEX and heat trace with black neoprene pipe covering.