Checking the pump connections for continuity is a good idea. A further possible cause of slow draining is debris trapped round the ball of the 'Eco-valve' page 3-10 of the manual in the following link refers: - secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/eab852a13fbc842085256aa200643dd6/$FILE/Duet%20Job%20Aid.pdf
,,,,,Your machine is manufacturd by Whirlpool and is essentially a re-badged 'Duet'. To avoid the 'mess' when removing the filter cover try connecting the suction hose of a wetvac to the discharge hose of the washer and sucking the water out. This will not work if the drain system is totally blocked. The link below details a similar problem and is eventual cure, I think. Good luck.