Water Problems

All reputed make motors are normally designed for contineous rating. This means motors can run 24x7 without halt.

You mention jet motor. It's termed as ejecto pumps or jet pumps. The motor driving these pumps are normal & standard sqirrel cage industion motors like any other motors.

Normally in a residential society, no one installs compressed air motor since it demands a compressor generating air & compressing into the tank. This is too expensive & unnecessary.

The water problem has two reasons:

1. Shoratge of water at the supply end.

2. Your landlord has wrong notions about electricity consumption. He perhaps is trying to save on electricity.

Arun

It sound as if you may be referring to an ejector. What kind it is, or what it does is not clear. However, when one sizes a pump for a sump (another word for a hole where liquid is collected) the gallon per minute rating of the pump is based upon how long you want the pump to spend pumping the liquid out.

It goes like this, water flows into the sump and it gradually fills. At the low level, the pump does not run. The FLOATS that activate the pump, are set so they wait for the sump to get a load of water before the pump turns on. This saves wear and tear on the pump.

Now the type of sump and pump I just described uses an electric motor with an impeller at the end of a shaft. The shaft is turned by the electric motor, when the float gets high enough that it reaches the preset point to activate the pump. Like flipping an electric switch.

Now there is another type of ejector known as a pneumatic ejector. This uses a shot of compressed air to push the liquid up out of the sump. One of the times this is useful is when the liquid has a lot of STUFF floating in it. It is also useful when one has to LIFT the water through a great height, over a long horizontal distance.

Both are set up so they do not run constantly.

Thanks for giving me an opportunity to tell you a little about what it is that a plumbing engineer does.

If you are intersted in knowing more look up www.aspe.org.

I was not able to gather from the information given whether he is talking about pumping wastewater or potable water. He mentions a "jet" pump. This would indicate well water to me. The compressor would be used to supply make-up air when the storage tank gets "water logged". This occurs when there is more water in the tank than normal and not enough air to accomplish the delivery of the water without the pump cycling repeatedly.

This is called a "hydropneumatic" system. The jet pump would supply water to the storage tank and pressurize that water by pushing it against a cushion of air in the top of the tank. When it is pressurized to the proper pressure setting, the jet pump stops. As water is discharged from the storage tank, the air expands to maintain delivery pressure against the water. When the low pressure setting is reached, the pump starts and raises the pressure to the operating level and the cycle begins again. Since the writer has indicated the existence of two jet pumps, it would be reasonable to assume that they alternate on successive pumping cycles.

Now for the compressor. The captive air that I mentioned which resides in the top of the storage tank can become depleted or reduced from various occurances. There may be a small leak in the piping which allows air to escape. Some of the air will actually dissolve in the water. Some of the air may escape during the pumping cycle. When any of these conditions arises, the amount of air is reduced. Therefore, when the water is being withdrawn from the tank, the air expands to a point where it no longer has the ability to discharge the water at a reasonable pressure and the pump is called upon to operate at a much shorter interval than designed. That makes the pump cycle on and off repeatedly at short intervals.

The compressor is then activated to make-up the lost air and return the tank system to its design settings and allows the pump more time between cycles. This would be a manual operation unless the pumps are wired such that they operate on the actual level in the storage tank rather than the pressure. Then the pressure switch would only operate the compressor to maintain the proper setting and the level control system would operate the pumps.

One thing that would greatly reduce the occurance of this phenomenon would be to utilize a "bladder tank". This is a diaphragm or membrane that separates the water from the air and reduces the possibility of air loss and reduces the need to make up the air in that bladder area.

This is probably a rather large water delivery system to supply water to a number of dwelling units or it woiuldn't have an installed compressed air system. My own water delivery system at home has a small tank that is not a bladder tank. I have to regularly take a small air compressor down and pump air into my tank to stop the pump from cyscling repeatedly.

Hope this helps.

Hi,

Please tell me if your Water Resourse is from Chennai Water Supply Board or Bore Wells dug by your builder.

May be bore Wells Motor delivery end seen on ground as JET Fixture is what you call Jet Motors. The PUMP is submercible inside Borewell lifts water from under-ground reservoir (aquifer) to Ground and or Over head Tank on terrace of the building.

There could be Dual Supply facility in your premises, one from Water Supply Authorities and the other from Own Bore Wells. Irrespective of this assumption, please detail what is the Water Problem....is it inadequate supply or Poor Water Quality?

google flow rate, head and look for it the name plates of the pumps. This research can help you in calculating the running/filling time.