The foreline pressure of TP2 was 1.4 Torr this morning. This drypump worked well for ten months.
Recently rebuilt drypump with new seal was swapped in.
This is how you do it: close V1, V4 and turn off TP2. Replace drypump and start up TP2
Set pump speed to 50 K rpm and open V4 to TP1 Note that the Maglev was not turned off because V4 was closed off only 5-10 minutes.
Open V1 the status is Vac Normal.
TP2 is rotating at 50K rpm, current pick up 0.2A, the temp is 26C and its foreline pressure 33 mTorr