Septic Tank Pump Question

[jsm]

All,
Hoping someone can help me. Just pulled my pump from my low-dose (low pressure pipe) system (very similar to aerobic, except no chlorine tank, and uses a drain field instead of sprinklers).

The person who originally installed it choked the ball valve going to the field lines to about 3/4 open. Not sure why - maybe trying to regulate flow to the field lines? Seems like this would just put unnecessary head pressure on the pump. It it a 1.5" PVC line.

Does anyone know the reason for that? Thinking about just setting it wide open when I re-install. Thanks in advance.

Joseph

 

[Jogeephus]

I agree with you. I would think this could put unnecessary stress on the motor. What little pressure increase would be short lived once it got a few inches from the valve so I really don't see the point. But I might be missing something.

 

[bear]

Low pressure dosing systems are engineered systems. The valve you are referring to is used to adjust flow to the field and was most likely set 3/4 open for the amount of pipe and perforations for your field. Each field is different. Some fields have multiple valves if installed in steep or sloping terrain.

Three quarters open will not significantly affect pump life.

Bear

 

[Brute 23]

Low pressure dosing systems are engineered systems. The valve you are referring to is used to adjust flow to the field and was most likely set 3/4 open for the amount of pipe and perforations for your field. Each field is different. Some fields have multiple valves if installed in steep or sloping terrain.

Three quarters open will not significantly affect pump life.

Bear

It sounds like that helps to maintain the "even distribution" the system is known for. It says you need some type of orfice (the valve) to regulate the flow.

 

[skyhightree1]

Low pressure dosing systems are engineered systems. The valve you are referring to is used to adjust flow to the field and was most likely set 3/4 open for the amount of pipe and perforations for your field. Each field is different. Some fields have multiple valves if installed in steep or sloping terrain.

Three quarters open will not significantly affect pump life.

Bear

:nod:

 

[jsm]

All, thanks for the replies. I guess I will just leave it alone. It sounds like the general thought is that 3/4 open won't burn the pump up prematurely. That was my concern. I appreciate the comments.....

Joseph

 

[greybeard]

Sprinkler head aerobic type systems have basically the same arrangement, but they use a minimum quantity of sprinklers and nozzle size to perform this function.

 

[Jogeephus]

If this is the last valve and its going into a drain field then why wouldn't you just have it wide open? Just trying to understand the reason.

 

[jsm]

Yeah, I hear you Jogeephus. Talked to a couple of buddies at work, they think I should leave it open (it is the only valve to the drain field). The pump does have a performance curve that requires a minimum fluid head, but that is already met with the height of lift out of the tank.

I would bet the installer was trying to set a certain GPM on the thing based on the calculated amount the drain field could handle based on the diameter and quantity of the perforation holes and length of pipe. That is all out the window at this point anyway, since there is some percentage of those holes that have plugged by now. There is probably some optimal absorption rate for each soil type that they were trying to meet (i.e. run too much water through and you get surface water or something). I really dont care about that, just want to maximize my pump life.

Thinking of just opening it all the way and leaving it that way. If I get standing water, I'll just back it off.

 

[Booneville]

I'm not sure what this system is but there are a few things that come to mind. If your pipes are above ground, there could be a chance of blown pipes or stress on the joints. It could also be this way to help your pump stay primed if there isn't a checkvalve or something to maintain water in the pipes.