Solar Pump. What will happen in this case?

[MJCM]

After Reading:  Please Do Not Suggest To Make The Pump Automatic.

 

We need to travel to Pattaya and Bangkok for a week or so (maybe more)

 

When we are away the BIL will take care of the garden.

 

We have the following setup

 

1- Water is pumped from a well into a Holding Lake (Solar Submersible)

2- That water is then pumped from the Lake via another Solar Pump to a Holding Tank which feeds the garden

3- This pump (#2) needs to be turned on / off manually

4- The Holding tank DOESN'T have Ball Valve installed (yet)

 

Suppose we install a Ball Valve in Holding Tank and we forget to turn off the Solar Pump.

 

Will there be a problem with the Solar Pump that stays on?

 

My guess I could expect a ruptured pipe somewhere.

 

What do you guys think?

 

Ps: Again, Please Do Not Suggest To Make The Pump Automatic. A very very long topic about that ALREADY exists and we don't have time to do that as we are already leaving in a couple of days.

[Crossy]

Running a centrifugal pump into a closed valve is unwise.

 

It's not likely to rupture your pipework but all the energy that's going into the pump will be converted into heat warming up the water that's inside the pump. It can get very warm!

 

Is the holding tank close enough to the well to run an overflow back to the well?

 

[MJCM]

Thx @Crossy

 

Unfortunately the Tank is approx 60-100m from the Lake and I haven't thought of an overflow, don't even see how that is possible to make as there is only 1 inlet and that is near the TOP on the side of the tank. (Outlet (1x) is on the bottom of the tank)

 

In all this time we only had the problem once that we forgot to turn the pump off and that the tank was overflowing, but I suspect with the BIL taking care that it will happen more then once and that Solar Pump pumps out a lot of water.  4000 Liter holding tank full in around 30-40 minutes (depends on the Sunshine of course)

 

Oke. So NO Ball Valve it is, just will call him every day and remind him to turn off the pump.

[MJCM]

Any thoughts on how to make an overflow?

 

So the tank looks like this

 

Red = Inlet

Blue = Outlet

 

And that are the only 2 on this tank.

 

Any thoughts?

 

Edit: Drill another hole on the opposite side of the inlet, but how to make it water tight?

 

[degrub]

Assuming the pump is on land, Just cut in a reducing T close to the pump discharge and either connect a 5-10 mm line/hose going back to pond or same with a spring upstream pressure regulating valve set for slightly less than the pump deadhead pressure.  
 

pump will turn itself off every night , correct ?

is the pump for the line from the lake to the tank also submersible? If so, dead heading should not matter.

 

it would help if we knew where there are check valves and other valves in the lines between the lake and the tank. Also, brand and model of pump, self priming, etc. 

 

most atmospheric tanks will have a vapor vent line on the roof to handle overflow conditions. If not, then rupturing the tank at a bottom seam is possible since the piping is usually stronger. 

 

 

 

[Muhendis]

In central heating systems which I once did for a short time, The centrifugal pump would have a small'ish pipe connected from it's input to its output. so that if the system pressure increased due to all the radiator valves being closed, the water would then choose the bypass pipe. 

Water likes to take the route of least resistance so under normal conditions the water would go down the larger bore pipe and fill the tank. Very little would take the bypass route. When the tank is full the ballcock or ball valve, yet to be fitted, will close and the water then takes the easier route from the pump output back to the input or source.

[MJCM]

Thx Guys

 

The Pump that Pumps water from the Lake to the TANK is NOT in Well.  It's a Solar Pump above ground which is connected via MAINLY HDPE pipe to the tank

 

20 minutes ago, degrub said:

pump will turn itself off every night , correct ?

Correct as it's powered via Solar

 

20 minutes ago, degrub said:

is the pump for the line from the lake to the tank also submersible? If so, dead heading should not matter.

Nope just a Normal Solar Pump above ground

 

20 minutes ago, degrub said:

Assuming the pump is on land, Just cut in a reducing T close to the pump discharge and either connect a 5-10 mm line/hose going back to pond

Wouldn't cause this for the tank to still overflow as that Pump (when in Full Sunshine) pumps out a LOT of water

 

This is the Pump

[degrub]

Where is the switch to turn the pump on/off ?

 

you could replace or supplement the switch with a timer  set to the minimum fill time from empty or less. 
 

i would not put in a block valve on the line to the tank in  any case without a relief path for deadhead that allows flow through the pump. This system does not appear to be designed to be blocked in and appears “safe” as designed. Steam/water explosions are nasty and will throw pump casing bits quite a ways . 
 

from the description, it appears there is already an overflow on the tank . Since it has happened before, i assume there was no harm to the tank. 
 

if you only have a couple days to deal with this, it sound s like calling bil daily is the plan. The worst case seems to be overflowing the tank for a while.

[MJCM]

5 minutes ago, degrub said:

Where is the switch to turn the pump on/off ?

Near the pump /  solar panels, so very close to the lake and 60-100m away from the holding tank. 

 

5 minutes ago, degrub said:

you could replace or supplement the switch with a timer  set to the minimum fill time from empty or less. 

Yeah but no idea how long to set it or when, because I have no idea at what time the BIL comes every day to water the plants (he lives 20k away)
 

5 minutes ago, degrub said:

from the description, it appears there is already an overflow on the tank . Since it has happened before, i assume there was no harm to the tank. 

Yes overflows via the lid on top, but I don’t want that happening to often as it will erode the sand under/side off the tank and as its a 4000 liter tank who knows what will happen. Also the pumps for the garden are close to the tank.
 

6 minutes ago, degrub said:

if you only have a couple days to deal with this, it sound s like calling bil daily is the plan. The worst case seems to be overflowing the tank for a while.

Worst case that it will overflow from morning till evening (when he forgot to turn it off) and that we definitely don’t want. Calling him every single day it will be then.

 

thx  

[rwill]

henna tatoo on his hand:

1 Turn pump on

2 water plants

3 turn pump off

[MJCM]

27 minutes ago, rwill said:

henna tatoo on his hand:

1 Turn pump on

2 water plants

3 turn pump off

We are away for 1 week+ maybe even 3-4 (OR more). Doubt that a henna tattoo will last that long

 

a Phone call a day is better

 

edit: and ideally it would be this sequence 

 

1- water garden

2- turn pump on

3- turn pump off when tank is nearly full.

 

so when the following day there is overcast he still can water the garden because the tank is full ???? 

[h90]

easy to do. You make the pump 2 automatic, but don't use the automatic, turn it manual on/off.

If someone forgets to turn it off the automatic will do it.

Some cheap water level switch costs almost nothing

[h90]

3 hours ago, Crossy said:

Running a centrifugal pump into a closed valve is unwise.

 

It's not likely to rupture your pipework but all the energy that's going into the pump will be converted into heat warming up the water that's inside the pump. It can get very warm!

 

Is the holding tank close enough to the well to run an overflow back to the well?

 

some brilliant people did just that with the pump that feed our house.

The pump shut off...half an hour later it worked again so someone wise installed a heat protection somewhere.

But on Aliexpress you can buy cheap heat "sensors" (it is not a sensor it just opens when it is too hot, but I don't know the correct name of it.) in steps 80,90,100,110, etc degree. Just glue one on the pump.

(most probably half a year later the pump doesn't work because that sensor is broken)

[MJCM]

6 minutes ago, h90 said:

easy to do. You make the pump 2 automatic, but don't use the automatic, turn it manual on/off.

If someone forgets to turn it off the automatic will do it.

Some cheap water level switch costs almost nothing

Have you read the OP? I ask specifically not to mention that as A) no time to do it B) don’t have the knowledge to do it.

 

already posted a long long time a topic about it and conclusion was NOT going to happen in the foreseeable future. 

[Crossy]

6 minutes ago, h90 said:

The pump shut off...half an hour later it worked again so someone wise installed a heat protection somewhere.

 

That would likely be the motor overheat protection, standard equipment in mains pumps. They have to get pretty darn hot to trip and it's not really good for them to go on/off all the time.

 

[LukKrueng]

4 hours ago, MJCM said:

What do you guys think?

How do you work out when you're there? Do you switch it on\off manually? If so, just show your bil how to do it.

[MJCM]

6 minutes ago, LukKrueng said:

How do you work out when you're there? Do you switch it on\off manually? If so, just show your bil how to do it.

I just wait at the tank and when it’s almost full walk to the pump and turn it off.

 

BIL is forgetful as …… and he just walks away goes and do other things and then forgets to turn off the pump

 

anf yes we have shown him how to do it. He was supposed to come by again today but he FORGOT ????

[Crossy]

Do you have a dog? Our two are better than quartz clocks when it comes to time for brekkie.

 

Even their 5kg could operate a switch to turn the pump on (and dispense brekkie) and they would hear the tank becoming full and turn off.

 

Easy peasy ???? 

[Crossy]

6 minutes ago, MJCM said:

…… and he just walks away goes and do other things and then forgets to turn off the pump

 

I do admit to over-filling Madam's koi pond on more than one occasion, mind gets involved in something else ...

[h90]

10 minutes ago, Crossy said:

Do you have a dog? Our two are better than quartz clocks when it comes to time for brekkie.

 

Even their 5kg could operate a switch to turn the pump on (and dispense brekkie) and they would hear the tank becoming full and turn off.

 

Easy peasy ???? 

Ours a foreigner could come in and steal everything including his food and he wouldn't care. If the water would be 30 cm high he would only hop up the sofa and continue sleeping

[MJCM]

12 minutes ago, Crossy said:

Do you have a dog? Our two are better than quartz clocks when it comes to time for brekkie.

 

Even their 5kg could operate a switch to turn the pump on (and dispense brekkie) and they would hear the tank becoming full and turn off.

 

Easy peasy ???? 

We have 2 dogs. But we feed them in the evening as else the crows will eat all tgeir food. Some pesky ones around

[MJCM]

I already showed the BIL how to set the alarm clock on his phone because usually I walk to the tank. See how full it is, walk to the pump, turn it on and set the alarm on my phone or wait at the tank
 

but i have now in total (i think) at least 5-6 times showed him how to do it, but every time he forgets. Heart of gold this guy, but his memory is like a sieve. 

[RocketDog]

17 hours ago, h90 said:

easy to do. You make the pump 2 automatic, but don't use the automatic, turn it manual on/off.

If someone forgets to turn it off the automatic will do it.

Some cheap water level switch costs almost nothing

You've got it on one. Best idea yet and easy to implement.

 

I use a float level switch in several such applications including my koi pond fill solenoid.

Mounting it onto the tank near the top is the only challenge. Of course the conduit wiring back to the solar tank should be robust. The final challenge is getting into the pump wiring to open the solar cell feed to the pump when the tank is full.

 

But the control logic you name is the simplest solution, but not achieved in the few hours the OP has left to work it.

 

 

[Crossy]

Please don't lose sight of the fact that this is a 750W DC pump, your regular level switches will fail almost immediately switching DC. It's not insurmountable of course but there's a whole thread about automating this particular set-up.

 

[Muhendis]

Mount a mobile phone on a three port solenoid valve so that when the mobile phone rings the valve will open allowing the pumped water to return to the point of origin thus no longer filling the tank.

Said solenoid valve is powered from the pump solar panel and reverts to tank filling state when night falls.

 

Ok back to serious solutions.

[Elkski]

You need to install a sprinkler timer and some pressure switches .  BIL can drink a beer and watch it finish watering. 

[bluejets]

18 hours ago, Crossy said:

your regular level switches will fail almost immediately switching DC.

Fairly simple mosfet switch would easily handle that....

[MJCM]

19 hours ago, Muhendis said:

Ok back to serious solutions.

And I thought that WAS your serious solution ????

[Muhendis]

32 minutes ago, MJCM said:

And I thought that WAS your serious solution ????

Could be done but I thought this forum was for the frugal approach.

[MJCM]

6 minutes ago, Muhendis said:

Could be done but I thought this forum was for the frugal approach.

I often (after reading some comments) sincerely doubt that