Re: Water Pressure Mystery
Is there an expansion tank above your water heater? (There should be.) If so, this could be the explanation. There are a few possibilities that I can envision:
- As water is heated, the expanding water backs up into the expansion tank. This results in an increase in pressure in the pipes (the water meter prevents the pressure from backflowing into the city main). When you open the faucet, you notice higher flow rate until the expansion tank is emptied.
- When water is not flowing, the city water main builds up pressure in your pipes until it reaches what is known as the "static pressure." When you open the faucet, this static pressure is held until the expansion tank empties. A restriction in the incoming line (such as at the water meter, a pressure reducer, or corroded pipes & fittings) causes a reduction in water pressure.
- You have a pressure regulator that is faulty and allows pressure to build up when water isn't flowing but is unable to maintain that pressure when water IS flowing.
The "Senior Member" designation under my name doesn't mean I know a lot, it just means I talk a lot.I've been a DIYer since I was 12 (thanks, Dad!). I have read several books on various home improvement topics. I do not have any current code books I can refer to. I was an apprentice plumber for two years.