Noise will generally only occur when the unit heats during the night or when requested by you during the day. The unit contains a copper cylinder holding 100 – 200 litres of water, which will make some noise when heated, in the same manner a kettle makes considerable noise when heating a far lower quantity of water.
Some noise is therefore unavoidable, however, if the noise level increases noticeably or you are concerned it is excessive, please do not hesitate to contact us.