Fresh Water Pressure adjustment

[MikeP]

Is there any sort of pressure switch that will allow the high/low cutoff/on to be somewhat closer? The standard switches I have used are essentially 20PSI apart. You can shift the entire range - go from say 20/40 to 30/50 - but you can't change it to 30/40. I would like to get it closer; any way to do that?

Also...I notice that the faucet flow "flutters." This occurs whether the pump is running or not so it's not pump-related. I'm thinking it's the flapper type check valves in the hot water system. Does that sound right?

 

[Avenger]

In a system with an accumulator it may not be as severe, but when trying to set up my SW washdown system I would get a rapid on-off cycling almost like the "water hammer" effect if the pressure differential wasn't big enough. Just a thought.

 

[GJH]

There are a number of switches that have one adjustment nut that raises or lowers both and one that adjusts only cut off. In fact that's the only kind I've seen. Merrill and Square D make them among others. Inexpensive too, most hardware stores have them. Your issue sounds like an accumulator tank problem; has anything changed in your plumbing recently?

 

[MikeP]

"There are a number of switches that have one adjustment nut that raises or lowers both and one that adjusts only cut off. "

I have one of the Square D switches that is supposed to allow that but I have never been able to adjust it so it will change the interval between high/low. The smaller spring acts on the same tab that the larger spring sits on. I have two more of those switches in other (home) water systems and they do the same thing. I have never been able to get the trip points any closer than around 18psi. I have tightened/loosened the small nut and all that ever happens is the same thing as happens with the larger nut, just not as quickly - it just shifts the top/bottom points but doesn't move them closer together.

Maybe I'm doing something really dumb but I can't figure out what. But I guess that's what being dumb is all about!

The accumulator is fine and set at the correct psi for the low side cut in.

 

[carolinacoast]

I just played with ours after learning at HOSchool that 60psi is fine. I could not get the gap down more than about 20psi, and now the pump cycles more. I ended up cranking the bigger spring nut in a good bit to get it to cut on at 30psi and off at close to 50. you're not alone, but my pressures stay pretty consistent at the faucets/shower heads.

 

[GJH]

The pressure switch wouldn't be the cause of "fluttering" when the pump is not operating. Perhaps your accumulator tank is waterlogged. Are you testing the air pressure in it with the system pressure at zero? The only other thing I can think of is a faulty check valve, but in my limited experience that just affects the pump's smoothness. I suppose if the valve is loose in some way, it could cause the issue, but I don't know.

I don't see the purpose of narrowing the cut-in cut out gap, other than put more hours on the pump. Admittedly, the times I have messed with the gap was to widen it when I was experiencing "chattering pump syndrome", the cause of which lay elsewhere. .