As mentioned in the review above, except for rooms facing the inner courtyard I think most of them face some aspect of LHR & runways, so yes you can easily get a room facing the runways. If that's something you'd like, you can have it put in the requests section of the reservation so you're not assigned an inner courtyard room. Or the reverse - if you're concerned about noise put a request for inner courtyard.
Whether the rooms are noisy or not depends on where/which runway they're facing I would imagine. For example, I've been in room 3172 that not only was facing a runway but had a service elevator next to it & I didn't hear noise from either. I was also originally slated this past weekend for room 3192 which was halfway down the runway when the planes were at full throttle for take-off & you could certainly hear the noise then, hence my request for a switch.
Cheers.