Cistern Water Pressure

[jrmylmach1]

Hello All,

I have a perplexing situation. Our house has a cistern as its water source. It collects the rain from the roof through the gutters. Inside the basement I have a 1hp pump that feeds into a 86 gallon pressure tank. It then goes through two filters and into the house. I am having trouble with the water pressure in the house. I replaced the pump and pressure tank in October 2015. The filter elements were replaced in February of this year.

Basically what is happening is we can run the water from one source and that is it. If you flush the toilet while taking a shower, you lose all pressure. I mean it goes down to just a trickle. My wife was telling me yesterday that the dishwasher isn't working right because of this as well.

I have the pressure switch set to 40/60 and it seems like it is coming on and shutting off when it is supposed to. I have taken the filter elements out to see if that improves things. It does but only marginally.

Does anyone have any advice or suggestions on what I could check next or what might be causing this?

Thanks,.

 

[Valveman]

First you need to make sure you have plenty of water in the storage tank. If you do, then you need to figure out why the pump cannot keep up with demand. Is the pump cycling on and off WHILE you are using water? Or does the pressure just drop really low like 10-20 PSI and just hang there WHILE you are using water?

My first guess is that you have something clogging the jet nozzle in the pump, and it cannot produce the flow and pressure needed, which would mean the pressure just stays low.

If the pump is cycling between 40 and 60 while you are using water, then you have a blockage after the pump somewhere.

 

[Sponsor]

 

[jrmylmach1]

Valveman, I believe that I have plenty of water in the tank. I can knock on it and it sounds solid up to about the 2/3 mark. Above that has the hollow sound. The pump only turns on when the pressure in the tank gets to around 38 or so and then turns off when it gets back up to 60. I have not seen the pressure drop to any lower than that.

Based on your thinking, I would say that there must be something blocking after the pump. Unfortunately I am in Japan now and won't be home until June 1st so can't do much troubleshooting yet. Are there any particular places that I should look for blockages? What about around the water softener? After the filters it goes to the water softener and then on to the hot water heater/house supply. I have the feeling I will be taking all of my pipes apart that I can get to to see if there is anything inside.

Thanks for the suggestions.

 

[Reach4]

Do you have a valve after the pressure tank and before the filters? How about removing one of the sumps (thing that the cartridge is in). Put a tub underneath to catch the water and turn on the water for a bit. Does water come gushing out? If so, your clog would be after that point.

Always lightly lube the O-ring on your filter when you put it back together. You should have a spare O-ring for the filters if you don't have a 3-valve bypass for the filters. Otherwise a failed O-ring would put you out of action.

 

[jrmylmach1]

Ok. I will do that when I get home. Can you explain more about how a failed o-ring will put me out of action? Does it block the flow of water? I didn't lube the o-rings the last time I changed the filters so I will check those as well.

 

[Reach4]

Ok. I will do that when I get home. Can you explain more about how a failed o-ring will put me out of action? Does it block the flow of water? I didn't lube the o-rings the last time I changed the filters so I will check those as well.

Sometimes an O-ring could swell, and you could not get it to seal leak-free. It could crack. Depending on how big the leak is, you might need to turn off the water until you get the new O-ring. This may never happen, but having an O-ring on standby is cheap insurance.

The main purpose of the lube is to let the rubber slip to fill any voids. There may or may not be a secondary purpose of the lube itself filling micro voids. I am not totally sure about that last part.

Do not use Vaseline or any other petroleum product on the rings. That swells the O-rings almost for sure.

 

[jrmylmach1]

Ok. Understand about the lube helping it seal and prevent leaks. I'll be sure and lube it next time I open it up. It's not leaking now though. I'm really thinking that I need to check where the filter system is connected to the pipes to see if there is any sediment build up in there blocking the flow. I really can't think of anyplace else that could be reducing the flow of the water.

 

[Craigpump]

I have seen people unwrap the filter but miss a piece of cellophane wrapping and it gets trapped in the filter head, blocking the flow.

You want to use plumbers grease or silicone grease on the O ring. The grease allows the Oring to slide rather than drag in the head so it doesn't stretch out of shape, the lube also allows the canister to seal and then be removed much easier.

You're not drinking that gutter water are you?

 

[jrmylmach1]

Yes, we do drink that gutter water. All of the houses around here use that as their only source of water. I'm sure that I didn't leave anything on the filters but that is a good thing to double check.

 

[Craigpump]

How are you sanitizing that water?

 

[jrmylmach1]

The only "sanitizing" we do is pouring a little bleach in the cistern once a month. The water we drink also goes through a reverse osmosis filter. The rest of the house is just filtered by two filters after it comes out of the tank. Haven't had any problems and the taste is better than the crap we get from the city at our rental house.

 

[Craigpump]

RO isn't really effective against bacteria, so you're drinking everything that's on the roof including bird doo.. Once a month treatment with chlorine helps, but I'd suggest a UV light just to be sure.

 

[jrmylmach1]

I'll look into that. Have any suggestions on good but not too expensive units?

 

[Craigpump]

There are plenty on the market. We use Sterilite units, they are super easy to service, the bulb and sleeve have to be replaced annually.

Clean, bacteria free water is priceless