The Hornets have won their last two home games, against Sheffield United and Bristol City, but are without a win on the road since beating Middlesbrough back in October.
"Obviously we are very comfortable playing at home in front of our own fans and in our home surroundings, it's all brilliant," said Harley.
Watford face a short trip to west London next Tuesday night to face QPR before heading to Scunthorpe the following weekend.
Harley added: "We have had some fantastic away results this season, at Nottingham Forest and Middlesbrough, so we can do it. It's now important we start doing it regularly."
Source: PA
Source: PA