I am having difficulty maintaining water pressure but can't seem to find a source. I am a marine pipefitter and have always done my own home plumbing stuff, the skill set isn't too different after all. Because my home is only about 50ft lower than the water tower supplying our community the water pressure is under 30 lbs. and I have had to install a booster pump to compensate. This pump is designed to add 40 lbs. of pressure to whatever the water pressure is so I also added a pressure regulator to keep the incoming pressure consistent and a spring assisted swing check valve to prevent the pressure from feeding back. I also installed a gauge to keep an eye on the current pressure. The pump cycles every 8 minutes meaning I am losing 40+ lbs. of pressure in that amount of time. I have a valve to isolate the entire house both before and after the pump. When I isolate the entire house, the pressure remains constant, which tells me the check valve is doing its job. Once that valve is opened the loss is immediate. My first suspect were the 3 toilets. I isolated all 3 at the angle stops and the pressure still drops. Next 3 bathroom sinks, same result. While I cannot isolate the showers, I have access to both the backs and bottoms of all 3 and there is no leakage. I can isolate my kitchen sink, dishwasher, and refrigerator and loss continues. I isolated to 2 outside hose bibs and still lose pressure. The last thing was the water heater. While I can only isolate it from the outlet side, when I installed it some years ago, I added a tattletale drain (since the relief valve drains outside) so I would know if it had relieved and it has not. So that effectively isolates everything in my house except the piping itself and the pressure still drops. I did a bit of math and determined I am losing about 10 ounces of water every 8 minutes based on an educated guess of the volume of the piping. That works out to about 10 gallons a day if my math is anywhere close, and this has been going on for weeks. I believe I would notice a monster wet spot, soaked carpets, mushy drywall, something if that much water is escaping. So, my 2 questions for the group are, 1) Can a piping system lose pressure without losing water and if so, how? 2) If number 1 is a no (and I suspect it is) what could I have missed?

Monitoring the water meter will tell you exactly how large a leak you have.

Problem is no meter. We are a small development with an HOA that charges all 65 houses the same amount and maintain the well, tank and infrastructure with the proceeds. If my math is somewhere close to right how much is covered (in theory). Its the where the heck is it going that has me baffled. Oh, and in my initial post I forgot the washing machine. Isolated, and you guessed it, still dropped pressure.

Is there in-ground piping between the pump outlet and the house/fixtures?

Nope.

Makes no sense, unless there's an in-ground pipe for landscaping that you are not aware of.

Boy, don't I know it. I have been wrestling with this for almost a month now. I can't think of any way for pressure inside the house to drop without leaving some sign of where it's getting out. One of the biggest reasons I'm reaching out. I've run out of ideas. I have the as builts to the house and have traced all the piping I can see and there is nothing I can't account for.

maybe shut off the valve on the pressure side of the pump andhit the system with 100 PSI of air ??

Could you be losing pressure without losing
water?
There are ways to measure water flow from
outside the pipe. I bet they're expensive.



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This was one of the questions I asked. I'm having a hard time coming up with a for instance on how that would be possible. My initial though was a toilet tank valve could be bleeding by and simply draining into the bowl and trickling down the drain. Quiet and transparent. But isolating all 3 toilets in the house didn't change the leak rate at all.

Not opposed to trying that but what would that tell me?

if 30 PSI of water is mysteriously disappearing then 100 PSI of air would also disappear but it would make more noise in doing so.

Interesting, thanks for the way forward. Ill let you know how it turns out.