bleeder valves and weep holes

[Slugboy6000]

Hello, I'm looking for a way to drain my plumbing back into my well.
It's a simple setup where I'd like to manually control my submersible well pump so that I can fill an open tank with water in freezing temps and let the plumbing drain itself between uses. I'm assuming that the bleeder type valves used in drain-back systems don't work without pressure and wonder if instead a weep hole in the drop pipe would be appropriate in this situation?

My pitless adapter is only 12" below grade due to bedrock, the supply line is insulated and the outlet emerges 8' away into an uninsulated shed.

Thanks

 

[LLigetfa]

I'm assuming that the bleeder type valves used in drain-back systems don't work without pressure

If you constrict the discharge at the top a little or set the bleeder deep enough, then the pressure at the bleeder should get high enough to close the bleeder. Friction loss between the bleeder and the discharge alone would probably be enough for it to close.

 

[Sponsor]

 

[Slugboy6000]

That's great, thank you very much LL.

With a 4' frost level, I think my only other question would be how deep a drain-back / bleeder valve should be to avoid freezing.
I really don't know what the temperature is like inside of a 20' steel well casing buried in limestone in the dead of winter.

 

[Valveman]

Heat from the earth will rise in the well casing. Usually pipe in the casing will not freeze. Installing a bleeder orifice too deep will keep it from opening. Just a pound or two will keep it closed, so you don't need a pressurized system to make it work. I would set a brass bleeder about 5' deep and no deeper than 10'.

 

[LLigetfa]

Installing a bleeder orifice too deep will keep it from opening. Just a pound or two will keep it closed, so you don't need a pressurized system to make it work.

Some bleeders spec no more than 10 PSI to open and even those may be special order with others requiring less pressure. The pressure needed to close one is not the same as what is needed to open one as flow is a factor. That said, if one opens at a higher pressure, it stands to reason that it might also need a higher pressure to close so I would design the system with some constriction depending on the depth and GPM of flow.

 

[Slugboy6000]

Lots to learn here, I appreciate the tips.
I do want to constrict the flow down to what will likely be a short length of potable garden hose. Unrestricted flow from my pump is too violent for my needs.
I can't find pressure specs for the two brass bleeders that I've been able to find so far (Boshart BOB07NL & Merrill BBONL75), but I should be sitting at around 4 psi (9' of head) when the pump is off.
I'll keep looking.

 

[Valveman]

The brass ones in the pic above will work. They just won't open if set 23' deep, which holds 10 PSI on them. Set them more shallow than 20' and they will work fine.