Working Of solenoid valve

[gsingh11]

Hi, I bought 2 solenoid valve from amazon. they are 12 V i wanted to use them in a water tank. I tried to test them running under water but they don't work. I don't know what is the problem.
https://www.amazon.ca/gp/product/B07BF8VGZF/ref=ox_sc_act_title_2?smid=A36ZH2MCHPKXUA&psc=1

[mikerj]

I tried to test them running under water but they don't work.

Do you mean you had the entire valve submerged in water?  They are not designed for that.

If you mean you tried to pass water through them but they do not open, what power source are you using to activate the valve?

[gsingh11]

I have a power supply. I didnt submerege it. I tried running it under tap water. Like pushing water through one end but it doesnt work. water doesnt go through it. i just hear a tick sound thats it.

[Twoflower]

Probably it needs a minimum pressure to operate. Lots of valves are pilot-operated. Those valves use the liquid-pressure to open/close. The solenoid only opens only a small channel and not the main channel. See https://en.wikipedia.org/wiki/Solenoid_valve#Pilot-operated

[langwadt]

I have a power supply. I didnt submerege it. I tried running it under tap water. Like pushing water through one end but it doesnt work. water doesnt go through it. i just hear a tick sound thats it.

did you have water pressure? was it the right way around (there should be an arrow in the flow direction)?

many valves use the pressure of the medium to open and close the valve

[gsingh11]

I have a power supply. I didnt submerege it. I tried running it under tap water. Like pushing water through one end but it doesnt work. water doesnt go through it. i just hear a tick sound thats it.

did you have water pressure? was it the right way around (there should be an arrow in the flow direction)?

many valves use the pressure of the medium to open and close the valve

I am going to use the valve to drain water form a 5-gallon tank. I am not sure if it will work or not? I think the tank should exert enough pressure to push the water through?

[DTJ]

The working pressure range for the valve is 0.02-0.8Mpa.

0.02MPa is 3PSI.

Have you got it hard plumbed to your tap or are you just like squirting water into it.

It needs a minimum of 3PSI into the inlet before it will operate.

Scheme water tap pressure should do it.

For your tank to open it it may struggle. A 2m tall tank will have a maximum pressure of just under 3PSI so it probably wont open the valve when full and definitely wont open it when the tank level has dropped.

[ebastler]

The working pressure range for the valve is 0.02-0.8Mpa.

Actually the stated operating range is 0.02-0.8 mpa, which I assume to mean miles per annum. So the water must flow very slowly. 

Always the hallmark of a quality product if the manufacturer can't even get the units right...

[jmelson]

The working pressure range for the valve is 0.02-0.8Mpa.

0.02MPa is 3PSI.

From the above, I am guessing this is a "pilot operated servo valve".  That means there is a tiny valve that is directly operated by the solenoid armature, this valve sends inlet water pressure to a larger valve that uses that pressure to move a valve piston or diaphragm.  For the low source pressure you have available, this is the wrong type of valve.  You need a valve that is directly operated by the solenoid.  It may require more coil current to operate this type of valve directly. 
Jon