I have a Sky+ box that I want to replace with a SKy HD box I had on multiroom at a different address.

Will It just work (without HD obviously) if I just switch the boxes. Are the boxes paired to the cards and will I have to get a new card.

box and card will be paired up

multiroom at different addresses? naughty

Not really, all above board. Seperate accounts. I am stopping multiroom on one and moving the HD box back and swapping out my old sky+ for the HD Box

Ill tell sky Im changing boxes and they can send me a new card I guess.

nah, you don't need a new card (unless on has been cancelled) also don't hint you need a new card, or they'll send you one and it won't fix the problem. they're not very clever there...
tell them you need to pair the card with a new box. you'll need the version number and serial number off the menus on the box, and it'll be done in seconds

thanks mate all good then hopefully
l

yeah, i had the misfortune of working for them for a few months
you'll get bbc/itv HD etc for free, but just make sure the idiot you speak to doesn't put the HD subs on when they add an HD box

The boxes and cards are rarely paired together these days in my experience.

Also, you can use 'T.38' compliant VoIP gear (an FXO unit one end and an FXS unit at the other) to connect a Sky box to a remote phone line. For example, if you wanted a box in one house to ring out from the phone line in another. I'll let you figure out why that would be useful

Chris