stand alone water res. feeding city water line

[Thomas D]

l have a water res. w/ a 1/6 hp sub pump connected to my city water line.....(.l do NOT want to add to or fill the water holding tank on the unit for fear of freezing)...l have very little pressure...the tank and pump are within 6 feet of city water connection..short hose...what can l do to increase water pressure?....Thanx in advance ppl.

[rockfordroo]

Bigger pump. Not much else you can do.

[5picker]

Sump pumps are not designed to build pressure.
If you are pumping water out of a reservoir into your city water connection, a sump pump isn't the correct style of pump to be using. You need something that will build pressure the same way your on-board pump does.

You don't mention anything about what model unit you have but if you have an antifreeze injection port on your unit, you could turn the valve to switch the pump's source to that supply, hook the antifreeze connection to the reservoir and use the on-board pump to pull water from the reservoir into the plumbing.

[Thomas D]

Originally Posted by 5picker

Sump pumps are not designed to build pressure.
If you are pumping water out of a reservoir into your city water connection, a sump pump isn't the correct style of pump to be using. You need something that will build pressure the same way your on-board pump does.

You don't mention anything about what model unit you have but if you have an antifreeze injection port on your unit, you could turn the valve to switch the pump's source to that supply, hook the antifreeze connection to the reservoir and use the on-board pump to pull water from the reservoir into the plumbing.

its a 2003 fr wildcat 5 th wheel...l dont think it has a antifreeze injection port.....

[Thomas D]

Originally Posted by Thomas D

its a 2003 fr wildcat 5 th wheel...l dont think it has a antifreeze injection port.....

the pump is right close to the city vonnection,just after the filtration...l have changed out the filter....but thats a great idea...thank you .

[rockfordroo]

To compare:

RV water pumps are diaphragm type pumps, meaning they are positive displacement pumps (PDP). PDP's put out (essentially) a constant flow at varying pressures. For example, this Shurflo pump puts out 3 gpm at up to 57psi (at which point the pressure switch shuts it off).

SHURFLO® REVOLUTION™ Pump 12 VDC 3.0 GPM | REVOLUTION™ 4008 Pumps

Your sump pump is a centrifugal pump, meaning it puts out more flow at low pressures and less flow at high pressures. I just bought a new ACE model ASF33 (1/3 hp) sump pump. Looking at the paperwork, it puts out 100 gal/hr at 20 ft of head. 100 gal/hr = 1.6 gal/min and 20 ft of head = ~9 psi. This isn't exact, but for an approximation, I would guess since your 1/6 hp pump is 1/2 as big as a 1/3 hp pump, you could expect about 1.6 divided by 2 = 0.8 gpm at 9 psi. So you're not going to get any appreciable flow or pressure from your sump pump.

You would need a sump pump that puts out 3 gpm at about 100 ft of head (45 psi); that would be a pretty big sump pump; I'd guess at least 3/4 hp. Here's a 3/4 hp Home Depot well pump that does 10 gpm at 100 ft of head:

http://www.homedepot.com/p/Everbilt-...22HD/205618055

I'm pretty sure this is a multiple stage pump (2 or 3 stages on the same shaft, to increase pressure) as opposed to the standard sump pump, which is single stage.

[extxn]

Originally Posted by Thomas D

l have a water res. w/ a 1/6 hp sub pump connected to my city water line.....(.l do NOT want to add to or fill the water holding tank on the unit for fear of freezing)...l have very little pressure...the tank and pump are within 6 feet of city water connection..short hose...what can l do to increase water pressure?....Thanx in advance ppl.

Talk to someone and see about getting a 'shallow well' pump and pressure tank! Just about anyone who may live in an area and has a dug well can tell you about them.
You cannot compress a liquid to create pressure but you use the liquid and pump with limit switches to compress the air in the tank to create pressure.
Google info up on shallow well pumps, they don't actually have to be in the ground.

Just an opinion of course ~~

[ProfChuck]

If you are drinking the water from this pump, remember it is not necessarily designed for drinking water and may contain hazardous chemicals like lead, etc. Better to get a potable water pump.

[onetonford]

Here is what you would need. A sump pump does not produce a pump curve to build pressure it is low rpm high volume. The well pump produces a pump curve to build pressure and is high rpm low volume. This unit is sold by Harbor freight and I have used them for boosting pressure for sprinklers.

[vasnipe]

X2 on onetonford.
I helped my Dad install one of these in his house. He was on a community water well and pressure was nonexistent at times. Took a suction on the incoming line and set the limit switches to suit him.

[Iwannacamp]

Originally Posted by rockfordroo

To compare:

RV water pumps are diaphragm type pumps, meaning they are positive displacement pumps (PDP). PDP's put out (essentially) a constant flow at varying pressures. For example, this Shurflo pump puts out 3 gpm at up to 57psi (at which point the pressure switch shuts it off).

SHURFLOÂ[emoji768] REVOLUTIONâ„¢ Pump 12 VDC 3.0 GPM | REVOLUTIONâ„¢ 4008 Pumps

Your sump pump is a centrifugal pump, meaning it puts out more flow at low pressures and less flow at high pressures. I just bought a new ACE model ASF33 (1/3 hp) sump pump. Looking at the paperwork, it puts out 100 gal/hr at 20 ft of head. 100 gal/hr = 1.6 gal/min and 20 ft of head = ~9 psi. This isn't exact, but for an approximation, I would guess since your 1/6 hp pump is 1/2 as big as a 1/3 hp pump, you could expect about 1.6 divided by 2 = 0.8 gpm at 9 psi. So you're not going to get any appreciable flow or pressure from your sump pump.

You would need a sump pump that puts out 3 gpm at about 100 ft of head (45 psi); that would be a pretty big sump pump; I'd guess at least 3/4 hp. Here's a 3/4 hp Home Depot well pump that does 10 gpm at 100 ft of head:

http://www.homedepot.com/p/Everbilt-...22HD/205618055

I'm pretty sure this is a multiple stage pump (2 or 3 stages on the same shaft, to increase pressure) as opposed to the standard sump pump, which is single stage.

Impressed.

[hinkle_e]

If you don't want to use an antifreeze hookup or modify your existing pump to have one, why not replace your sump pump with another diaphragm pump? You could toe in to your 12v lines with a waterproof connector and plumb it into the city water port. It's dry prime pump and, best of all, its a pressure demand system so you don't need to constantly turn it on or off. A quick Amazon search has them from $20 to $75 depending on flowrate.