Drain back lake water system help

[greidy]

I have been researching for a bit and have found a few points of confusion I need help with if someone would be so kind.
I recently took possession of a cottage in Northern Ontario, it seems to have the remnants of numerous water systems. At one point I believe it had a submersible (which is probably still in there somewhere as I see the big-o coming out of the water cut off..) In addition it seems to have had a heated line for the last 18 feet or so and a buried line in big-0 from the cottage to the lake with wiring that has been abandoned. It is currently setup with a simple land based jet pump and over land line.
So not sure if the old underground line is still usable or even if it is all that deep I thought I would utilize a drain back system so worse case the old line is useless I can run a surface run down to the water. Again hoping the wiring is still good there is also a backup run on that as well. The pitch down to the water is steep without valleys, about a 125 foot run dropping about 40-50ft to the water.
So for the tank I have an existing bladder tank, I have seen on some websites that a valve placed prior to this can be used to purge the air on pump startup others state you need an air volume controlled bladderless tank for this setup. Obviously having the tank already I would prefer the first option but need help to find the right valve (as I am useless with trade names for plumbing). Is the first option viable and if so what do I need to add to my current system and where? Second doing some reading I was thinking of using an SQE pump. Is this a good idea? Regardless of the pump my next question is do I remove the check valve or defeat it in the pump to allow the water to drain or do I add a "diverter" "bleeder" or other valve just above the pump? I would prefer the later but if possible what is the valve actually called? Being an electrician I can handle the wiring and the heated line from shoreline to pump.
Have I covered all the alterations I would need to make to my current system?
Also is it possible to setup the system so that in summer you leave the system primed like normal? Would it be as simple as plugging the air intake valve thingy at the top of the system

Many thanks to anyone that can pint me in the right direction.

Geoff

 

[Reach4]

what is the valve actually called?

Try this search in a search engine: snifter "drain back"

 

[Sponsor]

 

[Valveman]

The SQ is not a bad pump. But when used with the CU301 variable speed controller it becomes a SQE, and is not dependable. A simple air relief valve prior to the pressure tank will vent air on start up. However, it is also possible to just leave the faucets open in the house when starting the pump first time of the year, and the air will just come out the faucets. You will need to get the air out all the way to the faucets anyway.

A bleeder orifice under the water and after the pump will work to drain the system. You have to leave the check valve in the pump, so the bleeder or a manual valve is the only way to drain the system. With the bleeder orifice installed, there can be no check valves after the bleeder. Draining the system is easy, as you just turn off power to the pump and open some faucets. When the tank is depleted the lack of pressure will cause the bleeder to open and drain everything from the faucets to the bleeder. However, 40'-50' of head all by itself is enough to keep most bleeders from opening. You will need two or three of these.
https://www.menards.com/main/plumbi...ss-bleeder-orifice/bo75nl/p-1444446043320.htm

Place one under water by the pump and another one about every 15' up the hill. The top one will drain first, taking the pressure off the lower ones, then they will open and finish draining the system.

 

[Reach4]

In addition it seems to have had a heated line for the last 18 feet or so and a buried line in big-0 from the cottage to the lake with wiring that has been abandoned.

I had to look up big-o. I was surprised at what I found-- yard drain pipe.

I presume that pipe is used as a conduit for poly tubing and wire.

So is the thought to get the water out of the poly pipe just down to the heated area, and would only be done a time or two per year? If so, how about an above-water valve above water to release water?

I was imagining another system that would not require heat to be run through the winter. How about a pressure relief valve near the pump. Maybe set to 150 psi, or whatever is appropriated. Turn off power to the pump. Run air in with a compressor. That blows water out of the poly pipe under water. When you see bubbles, or the air pressure rises and levels out to 150, you shut down the compressor. Just a thought. No relevant experience.

 

[greidy]

Thanks Everyone. You have cleared up the trade name issues for me. To re-iterate I will be using this off and on during the colder months but not in the dead of winter. My fear was freezing during the overnight while I am there and something simpler to "winterize" when I am gone.
So if I compile my research and the comments above I think I will go with a standard pump no need for the extra for the SQE. Add a T with a Bleeder Orifice just above the pump underwater (does this have to be oirnetated in a particular way like T up or down?) then add another bleeder 15 feet up (Good suggestion would have never thought the head pressure would lock it) , then add a new check valve prior to the tank with two holes adding the Snifter valve to allow air in. That should take care of the issue of draining the main line.
Since I don't want to have to deal with Air in the lines I think I need to replace my Bladder tank with a standard tank with Air volume control and I should be good to go. Then heat and insulate the small section between shore and pump.
And yes Big-o is for protection to bundle poly, wiring and insulation.
Am I on the right track?
Is there any other valving I could add so I don't have to chnage my tank, and I still will not have air issue at the fixtures?

Thanks again

 

[Valveman]

Use an air vent/vac valve on a tee before a regular check valve. Something like this.
https://www.amazon.com/Netafim-TLAVRV-Vacuum-Relief-Vent/dp/B07GZRMR8W/ref=sr_1_fkmr0_2?ie=UTF8&qid=1539807412&sr=8-2-fkmr0&keywords=netafim+3/4+air+valve

A diaphragm tank will work fine. But you will need a tank large enough to supply the flow needed while waiting for the pump to start and all the air to get out, opening the check valve and putting water to the tank and house. I would probably use a 44 gallon size tank with a lower than normal air charge. What size tank do you have? With a 40/60 switch I would put in about about 25 PSI air charge in the tank. That way when the pump is told to come on at 40 PSI, the tank will still be supplying water to the house as the pressure continues to drop, hopefully not to less than 25 PSI. This will give time for the air to get out of the line, pressure to come up, and water to start refilling the tank and supplying the house. Every time the pump shuts off. the check valve takes the pressure off the bleeder orifice, which opens. The line drains from the check valve to the water surface, and nothing will freeze.

If the water hesitates coming out of the faucet, reduce the air charge in the tank to 20 PSI. If you get air in the house lines, use a larger or an extra air vent valve before the check valve.

 

[greidy]

Great thanks again now it almost all makes sense! Anyone know of a source in Toronto that keeps these kinds of valves on the shelf? Having a hell of a time finding the bleeder and the vacuum/air valves..
Really appreciate all the help guys!

 

[greidy]

I was just about to go and start building a pump stand like this one https://heatline.com/documents/subm...ke Applications Installation Instructions.pdf and thought to myself is the only reason ABS not listed for potable water a result of operating pressures or temp ? or does it pose a health risk from leaching something?