At an inspection and notice when I turn on a faucet there is an initial burst of water then it returns to a steady flow, similar to a garden hose. The water pressure is normal. House is 8 years old and has pex pipe. Homeowner also said he just started noticing it but only when it’s been off for a long period of time, say overnight. I’m in Charlotte, NC where we’ve have a few nights lately in the 20’s. Could it be the pipes are freezing and then expanding when it warms back up? Is there a potential for a water line break?
feed pipes allow Pressure to equalise in the system with no flow .
restriction could be the shut off tap is only partly on .
Or small lines from supply or extremely long lines from supply .
Did the water heater have an expansion tank?
Is it public or private water supply?
Stephen, my guess also. Many cities and HWH manufacturers are now requiring expansion tank installations. Many cities now have electronic meters that do not allow water back flow, and expansion back flow, when water is heated. This causes momentary high pressure in the system. New PEX lines do not allow for this expansion either.
If expansion tank is missing, recommend one. There is a good NACHI article on expansion tanks.