We recommend that a qualified licensed contractor perform this type of winterization method. The blowout method utilizes an air compressor with a cubic foot per minute (CFM) rating of 80-100 for any mainline of 2" or less. The compressor is attached to the mainline via a quick coupler, hose bib, or other type connection, which is located beyond the backflow device. Compressed air should not be blown through any backflow or flow meter device. For additional winterization procedures, we highly recommend contacting the local dealer for the most common local practices. In the event you need to blow upstream from where the flow meter is located, we recommend bypassing the meter by temporarily using one of two options.
Winterizing Using PVC Nipple Bypass Option |
Installing a SCH 80 or galvanized nipple. See the size chart below:
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Model | Description |
Male-Thread NPT |
Nipple Length |
HC-075-FLOW | ¾" NPT body, male thread with 1" NPT male adapter | 1" NPT | 5" |
HC-100-FLOW | 1" NPT body, male thread with 1.5" NPT male adapter | 1 ¼"NPT | 5" |
HC-150-FLOW | 1½" NPT body, male thread with 2" NPT male adapter | 2"NPT | 11 3/4" |
HC-200-FLOW | 2" NPT body, male thread with 3" NPT male adapter | 2 1/2"BSP | 11 3/4" |
Winterizing Using PVC Diverter Option |
A second option would be to install PVC tee diverters but this is done more efficiently during NEW installation. The meter will have to be removed manually after the blowout to make sure any residual water is not sitting inside through the winter months.
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