Electric sap releaser question

[PARKER MAPLE]

So I just picked up a used lap elec sap releaser. I think it's quit old but I like it because I can over come mu elevation problem by setting on the floor of the sap shed and then it will pump it up 8' to the tank location.

So I was in my basement setting it up for a trial run it was all going great until the pump kicked on the empty the tank and nothing happened. So I unplugged the vac pump and then the sap pump emptied the releaser with no problem. What I noticed is off the sap pump there is a small 1/2" Lin that runs from pump head to the top of the releaser can, I noticed sap was shooting back into the can and not out the discharge line. What is the purpose of this line going bank into the releaser. Can I just take it off and do away with it.

This is the down fall sometimes of buying a used rig, you never no if it's setup correct or if it's something your doing wrong.

Thanks for any advice or ideas to try in advance

Parker Maple

[GeneralStark]

At what vac. level were you running? It sounds like this is an old style electric releaser with an external pump, likely a shallow well jet pump. These pumps can't compete with vacuum levels much over 20" or so.

The 1/2" line is to help prevent the pump from air-locking but it sounds like it is not helping. Generally there is a check valve involved as well.

There is a reason this style of releaser is no longer being sold, at least not for high vac. situations. You would be better off acquiring a submersible high head pump like a sta-rite to put inside the chamber. This is how electric releasers are being set-up now.

If you are only looking to run up to 20", you may be ok with the present set-up, but even then the seals in the pump will likely fail if they have not already.

Just to clarify, the sap pump did turn on, but it did not pump?

[PARKER MAPLE]

Correct the sap pump came on as it should but didn't pump out. I then turn off the vac pump(while sap pump was still on) and the sap pump pumped out. I didn't have the vacuum cranked right up either maybe 15" max as I was just getting a feel for how this was all going to work. How major of a job is it to convert this over to an internal pump style releaser? Where can I get a sump pump for this type application ?

[wiam]

Is there a working check valve in this 1/2" line? Thad on here has 1000s of taps coming into this style releaser with high vac. I have run one quite a bit older but I put a stainless Goulds pump that had no problem at 15".

[maplecrest]

With out that line running back in releaser it will air lock ,and sap will run thru pump
After releaser fills.

[PARKER MAPLE]

I don't no if it's a working cv I will start there by replacing it. I was hoping to run it at 25" or so. I just check amazon I can get a 4" submersible pump for 150$ if I need to I will go this way.

[claytski]

General Stark you are correct. Lots of times the shallow well pump is not sized correctly for the application and there are problems from day one. On another note, if it is sized correctly, shallow well pumps do not have the pump curve for pumping out of releasers. They work if they are brand new and there is no wear on the pump. However, when the pump impellers wear some, the pump cannot keep up, and the sap overcomes the releaser. I modified a few releasers last season for a customer that had this very issue. I took the Bernard releasers and put submersible pumps in.

If the pump is up to spec, there could be an air issue where there is a vacuum leak in the wrong spot keeping the pump from performing. Even when these pumps do operate, I feel a little gun shy and nervous leaving them alone. Its great when you can check on the releaser often, but if it is in a remote place, and you have a problem, you really have a problem.

We have been modifying releasers for customers for years and adding submersible pumps. We only had one issue and that was when a customer called back three years after purchasing a releaser and told us he needed a new pump. He forgot to drain everything for the winter and lets just say the internal parts of the pumps do not like freezing.

[maple flats]

I may be all wet, but I wonder if the small line from down stream of the pump back to the tank is to put the pump in a vacuum environment so it can pump. I've been told (but have not tried it yet) that I could pump from my vacuum tank if I run a 5/16 line from after the pump, back to the vacuum tank. I was told that doing this put the pump in a vacuum and then it could pump the sap where it would not pump fighting a vacuum. Your situation sounds the same. You might have another issue. Is the impeller worn too much?

[wiam]

That is what that line does Dave. The check valve remains open as long as there is vac on both sides. As soon as pump starts the check valve will close and all sap will go to tank.

[PARKER MAPLE]

Which way should the CV be pointing? This one was pointing towards the sap pump not the releaser?

[wiam]

Which way should the CV be pointing? This one was pointing towards the sap pump not the releaser?

Hopefully it is a swing check and it should swing shut when the pump pushes sap through that line.

[Tmeeeh]

Hopefully it is a swing check and it should swing shut when the pump pushes sap through that line.

Mine is a swing check with a very small hole drilled in it so some sap goes back into the releaser when the water pump is running. This ensures the water pump does not air lock. We run 26" of vacuum and have no problem pumping tha sap out of the releaser against the vacuum. Our water pump is a goulds stainless steel pump. We have another releaser that has the pump inside it. If I were in the market for a releaser I would go with the pump inside the releaser kind.

[PARKER MAPLE]

We'll I have tried everything. All possible combos with the CV, tried without CV. I think pump ia air locking. How do you over come a air lock situation with this style pump?

[GeneralStark]

If you look at post #12, Tim refers to a hole drilled in the valve gate to allow some sap to go back to releaser. This is also necessary on the outlet of the pump in internal sump pump style electric releasers to prevent air locking. Essentially you are allowing the vacuum to help pull the sap through the pump.

I don't know if you can post any photos of this unit, or at the least let us know the model of the releaser and the sap pump. It is certainly possible that the pump is just worn and won't function correctly under vacuum at this point, but there may be something else we are missing.

[WMF]

Pull the releaser to a high vacuum and shut off the vacuum pump and anything else that makes noise . Listen for air leaks or gurgling around all fittings and especially around pump.
The shaft seal may be leaking or a pump casing may have a leak. Even a small leak will pull air into and liquid out of the pump head and it will not prime and pump.
If there is air and water moving through the line that goes to the check valve when the water pump is off there is air leaking into the system and it is being pulled through this line.
I have never taken a pump apart that is on a releaser that the impeller did not have some junk wound into it, usually plastic shavings from putting in saddles. This can make them pump slow or if really bad make them not prime.

[PARKER MAPLE]

Well guys it all came to an end the other day. The sap pump just up and stopped. I think that was the problem all along. Seized up tight.. Oh well, so now I'm going to do the internal sump pump conversion. Going to put the 1/2hp Ss sump in and do the continuity switch. Sounds like it shouldn't be all that complicated to do.. Thanks for all the suggestion and help.

Parker Maple

[500592]

Sounds like it was probably air locked and melted the impeller to the Venturi I think that's the right name I can't remember exactly right now.

[claytski]

If you look at post #12, Tim refers to a hole drilled in the valve gate to allow some sap to go back to releaser. This is also necessary on the outlet of the pump in internal sump pump style electric releasers to prevent air locking. Essentially you are allowing the vacuum to help pull the sap through the pump.

.

You and Tim are correct with that statement. When building releasers for customers I use a submersible well style pump. This style pump does not need the modification you speak of. I do not use the sump style pump you speak of because there is oil in the pump for shaft lubrication. Between the frequent start/stops of the pumps and the environments they are placed under, I am seeing frequent failures at this point in the pump and I believe no one wants oil in the sap. There is a feeling of safety by maple consumers that the pump is ok because it is stainless. I am only seeing the failures because the customer will call me to ask if there is a solution to fix the problem they are having with the competitors pump/releasers they purchased.

Also the sump style pump does not lend itself to constant level controls and other controls I implement. This is a function of pump type and design.

I am bringing this all up in possibly guiding you to the correct pump from past and present experience.

[PARKER MAPLE]

Thank you Clayton I will talk to you soon

[GeneralStark]

You and Tim are correct with that statement. When building releasers for customers I use a submersible well style pump. This style pump does not need the modification you speak of. I do not use the sump style pump you speak of because there is oil in the pump for shaft lubrication. Between the frequent start/stops of the pumps and the environments they are placed under, I am seeing frequent failures at this point in the pump and I believe no one wants oil in the sap. There is a feeling of safety by maple consumers that the pump is ok because it is stainless. I am only seeing the failures because the customer will call me to ask if there is a solution to fix the problem they are having with the competitors pump/releasers they purchased.

Also the sump style pump does not lend itself to constant level controls and other controls I implement. This is a function of pump type and design.

I am bringing this all up in possibly guiding you to the correct pump from past and present experience.

You raise some interesting points. I only have one season on my Goulds submersible, so clearly not time tested. I am curious if the failures you have seen of this style pump in electric releasers has resulted in the mechanical seal being compromised and allowing oil to enter the sap.

I think the feeling of safety in regards to using this style of pump is related to more than just the fact that it is made of SS. They are also made for potable water applications, and have FDA approved components. Additionally the pump curve, at least for the model I am using, suggests that these high head submersible pumps are more than adequate for the job, at least in my application.

That said, this certainly may not always be the case in every situation and there are several different pumps to choose from in this category.

[claytski]

The issues stem from being in a vacuum environment coupled with operating for only fractions of a minute. The excessive cycling of the pump and the vacuum environment have its way on the sealing portion of the pump. The smaller pumps are supposed to be operated for 1 minute minimum. Depending on the releaser size and volume, this can provide excessive cycling to the pump.

You may never have an issue with your setup. However, I am just shedding light on the issues I have seen in the past....

[PerryFamily]

Having dealt fairly extensively with water pumps both submersible and jet style nothing will kill a motor faster than rapid cycling, on off on off....
Rarely do the fluid ends give a problem unless the well water had a lot of sediment wearing on the impellers. However this is not in a vacuum environment.
Being that the submersible pushes fluid versus a external jet that sucks fluid the submersible isn't succeptable to air lock
Just a dirt guys 2¢

[Super Sapper]

There are times that submersibles do get air locked. If you have a discharge check with liquid pushing down on it and get gasses in the pump to displace the liquid they will air lock. I have seen this mostly with sump pits that sit for long periods before needing to be pumped. I could see this in a vacuum situation but a small hole in the line just after the pump and before the check would solve this.

[PerryFamily]

In my experience I haven't seen a submersible pump in a water well environment air lock. Most pumps we carried ( Gould's/ sta-rite/grundfos) have a check valve in the pump and are hundreds of feet deep. Just my experience

[Super Sapper]

You are probably correct in that situation with that style of submersible pump. My experience is in the waste water industry for the last 27 years and in situations where the pump is constantly submerged and cycles often enough it should not air lock, but if it pumps the vessel dry and fills it can air lock.

[PerryFamily]

Makes sense Super Sapper. I'm sure that in a high vacuum environment everything is different

[Super Sapper]

I don't have any vacuum experinence in the maple industry but am trying to help with my experiences in simular situations if it can apply. I don't have an RO yet either but have had to learn and trouble shoot RO systems in the cheese and whey plants back in the early 90's becasue of the impact it had on the waste water systems. I have learned so much here that I just would like to give back if I can.

[mrb215]

What do you recommend for pump specs??

[PARKER MAPLE]

What do you recommend for pump specs??

I have had a 1/2hp 110v strarite for 2yrs now with out any problems.

[Amber Gold]

I have a 1/2hp sta-rite inside a Lapierre vertical electric and I have seen it air lock. I solved that issue by drilling a couple pinholes in the discharge pipe just above the pump and haven't had a problem since.

[morningstarfarm]

Have an arablo elec releaser that had an external pump...bush has about 3500 taps in it and thvac pulls around 27-28"... Thinking of putting in a submersible pump for next year...any suggestions on a pump?
Thx chris