When there is a contradiction between the Shulchan Aruch Harav and his siddur,which one does the poskim use?
Which posekim ?– Double AA ♦Jan 17, 2014 at 0:17
Chayei Adam for example– samJan 17, 2014 at 0:19
Sry I meant the Kitzur– samJan 17, 2014 at 0:31
Although there was some initial confusion on this question among some poskim, because the Siddur was printed during the Alter Rebbe's lifetime, where as the Shulchan Aruch was only printed after his passing (even though he wrote the Shulchan Aruch when he was 26 years old), his children write that the Siddur was written later than the Shulchan Aruch, therefore it is the Mishna Achrona and what is considered his psak.
This is the Chabad practice as well.
Sources: This letter from the Rebbe in the appendix to Sefer Haminhagim (Chabad) (English), the letter preceding that, the Tzemach Tzedek's chiddushim on Mishnayos, 46b, the introduction to the new print of the Shulchan Aruch HaRav, references ad loc., and elsewhere.
Who was confused? Jan 17, 2014 at 2:33
@ShmuelBrin, I forget the name. I remember it was a discussion around the time of Shekia (Geonim vs. Rabbeinu Tam) and someone was saying the Shulchan Aruch superseded the Siddur on the matter.– YishaiJan 17, 2014 at 3:20
I think both answers here are discussing the minhag Chabad, but the questioner was asking about other poskim like the Chayei Adam and the Kitzur Shulchan Aruch. I'm guessing that they generally used the Shulchan Aruch Harav. That has certainly been the case in the examples I've seen (which are mostly in the Aruch Hashulchan and the Mishnah Berurah).– MichoelRJan 27 at 4:12
The Piskei HaSiddur was written according to nistar, but his Shulchan Aruch was written according to nigle. We do have a bit of his second Shulchan Aruch where he wrote only according to nistar, but most of it is lost.
Having said that, the Rebbe sometimes did something not according to the piskei hasiddur like not making a knot in the back of the hand tefillin with the extra string. There are also cases when we follow the rulings of the Tzemach Tzedek against the Shulchan Aruch Harav.
Check with your local Chabad rabbi as per which opinion is minhag chabad.