posted this 08 December 2017
Unfortunately all pumps that pressurise the water make a noise. The noise has been described as between a washing machine on spin cycle and a vacuum cleaner but every installation is different and a bad installation can make the pump much louder.
The best thing to sit the pump on is a small piece of paving with some carpet or a rubber mat under the slab. If it's on a wooden floor the sound can travel along the wood.
If the airing cupboard is empty then once it is full of towels etc that will help to muffle the noise.
The hoses attached to the pump need to be as straight as possible, if they are bent over or kinked the pump will be louder. Also the hot water temperature needs to be controlled, if its much over 60°C that will make the pump noisier.