Sump Questions

[ryan111]

I recently bought a house with a sump pump. In the last month, it has got stuck and stopped working and then got stuck on and almost burned up. I am thinking I am going to replace it. Should I go with a submersible or non-submersible? Also, the line is over 100 ft. long ( it runs about 35ft along the basement wall before going out)and I would say atleast half of it is graded back toward the sump (it leaves the basement about 6ft below grade) Should I install a check valve? I live in Michigan and it is about 18 F out right now and I am concerned the line might freeze if I do. The sump gets a lot of water.. it runs several times an hour lately.

Also, there is quite a bit of junk at the bottom.. is there any good way to clean it out or should I just leave it?

Any help would be appreciated...

Thanks!!

[LazyPup]

Although both the Pedastal type and fully submersible type are equally efficient I personaly prefer the submersible type for a number of reasons.
1. With the pump motor summersed in the water it tends to cool the motor more efficiently.
2. Normally the float switch for a submersible is concealed in a sealed plastic bulb and attached by means of a flexible electrical cord. That means there are no external linkages, guide bushings or other mechanical devices that might interfere with its proper operation.
3. The entire pump and control system is concealed in the sump pit where it will not be tampered with by children, pets or personal items stored in the basement.
4. The water cover tends to reduce operating noise.
5. It precludes the possibility of flooding the motor. (Recently we had a very bad storm and the power was out. Many basements flooded above the top of the pedastal type sump pumps before the power could be restored, which resulted in motor failures, and potentially an electrical hazard if the power were to come on and attempt to start the open frame pump motor while under water.)

Most sump pumps have capacity tables printed on the carton or in the owners manual. Typically a sump pump will discharge 30 gal/min into a 2" diameter line with no more than an 8ft lift.

Increasing the height of the lift will dramatically reduce the rate of discharge.

Often people tend to reduce the discharge line to 1 1/2". While the instruction manuals do offer that option, keep in mind that reducing the line even slightly has a dramatic effect on efficiency. When comparing pipe ratio you must divide the square of the large diameter x the square of the small diameter.

where the large diameter = 2"
small diameter = 1.5"
(2x2) / (1.5 x 1.5) - 4 / 2.25 = 1.78
thus a 2" line has the capacity of 1.78 1.5" lines.
From the math you can see that running the 2" line nearly doubles the capacity.

Capacity is again effected by line pitch and the internal resistance of the pipe. Simply stated, the longer the run, the more resistance which results in reduced flow.

A 2" pipe is required to be run with a 1/4"/ft pitch. Given that your run is 35 feet, the required drop should be .25 x 35 = 8.75". Keep in mind that this is code minimum and increasing the pitch will also increase the rate of flow. You stated that your line goes through the foundation at approximately 6ft above the floor and assuming an 8 ft ceiling, you have 24" of pitch available. Increasing the pitch will compensate for internal line resistance which should work out to maintaining a good full flow.

There are a few code considerations you should be aware of.

A sump pump is a variation of a special waste sewage ejector pump.

The vertical riser from the sump pump must rise above the gravity drain line, and must attach to the top of the gravity line by means of a WYE fitting.

There must be a backwater valve(check valve) on the riser.

There must be a check valve above the backwater valve on the riser.

There must be a cleanout on the end of the horizontal gravity drain.

There should be a union below the check valve to permit removing the pump or check valve for servicing. (Commonly the check valve is attached to the gate valve by means of a rubber Fernco coupling.)

All pipe and fittings must be listed "DWV" (Drain, waste & Vent fittings).

PVC and ABS may not be glued togther. Run the entire system in either PVC or ABS.

You may not use metal hangers or strapping to support PVC or ABS pipe. (Use PVC J-hooks, PVC strap hangers or PVC perforated strapping.)

The line is required to be sleeved where it passes through the masonary wall. To make a sleeve a piece of pipe two nominal trade sizes larger in diameter is first passed through the wall so that it extends at least 2" on either side of the wall. The sleeve may be sealed to the wall by any suitable means (cast into the concrete, sealed with pitch tar, mortar, expansion foam , etc.) The desired pipe is then run through the sleeve and the opening between the outside wall of the desired pipe and the inner wall of the sleeve is filled with expansion foam.

The minimum diameter line below grade is 3"

Must be 6" below frost line.

I am curious where the line terminates after it goes through the foundation wall? Most jurisdictions prohibit discharging storm drainage (sump pumps) into the sanitary sewer system.