Thank you for your question, loski! The purpose of the test cap it to ensure water flow is directed appropriately to the shower head, hand shower or jets that are installed and that there are no leak points. Before this is accomplished, however, the valve flush should be performed. It is recommended that the water is turned off to this unit, room or home prior to flushing. Once the water is off, the test caps can then be removed and you can turn the water back on slowly until reaching a full, mixed flow, flushing out any debris for up to a full minute.
Best regards, Edward
Date published: 2018-08-26