The twin tub connected to the washing machine doesn't drain.

use a drain cleaner to remove the soap and gunk build up in the sink section

see the causes and fix it. God bless you
If your washer won't drain, check these: It spins, but doesn't pump It doesn't spin or pump It pumps, but the water returns It spins, but doesn't pump If your washer spins but doesn't pump the water out, the drain line is probably clogged. In many washers, a small sock or other piece of clothing can get between the clothes tub and the outer tub that holds the water. If the clothing gets between the tubs, it may then get into the drain hose that's attached to the pump--or even into the pump itself. If it's in the pump, you need to remove the hoses from the pump and pull the item out. To remove the sock from the outer tub port, open the washer's main access panel and remove the large-diameter rubber hose that connects the pump to the bottom of the outer tub. Then, using needle-nose pliers, try to grab and remove the clothing through the port. Sometimes you can't remove the stuck clothing from below. Then you have to remove the agitator, top of the outer drum shield, and inner clothes tub. This isn't easy to do--and you may need special tools--so you might be happier getting a qualified appliance repair technician to do the job. If the drain line isn't plugged, the problem may be with your pump. Even if the pump appears to be turning, the internal impeller may be broken. If so, you need to replace the pump. It doesn't spin or pump If your washer doesn't spin or pump water out but the motor is running, your washer probably has a frozen pump pulley. If so, you need to replace the pump. To check the pulley, remove the pump from the washer and try to rotate the pulley manually. If it doesn't turn freely--if it's frozen or stiff--replace it. It pumps, but the water returns If the water that pumps out of the machine goes back into the machine after the spin cycle, your washer may be siphoning the water from a laundry tub that has a slow drain, back into the washer. The usual remedy for this is to improve the draining of the laundry tub. (Is something stuck in the drain?) Also, check for these problems: If the drain hose reaches more than about 4 inches into the laundry tub, cut off the excess. If your drain hose is lower than the washer's cabinet, install an air gap/siphon break assembly.

see the next steps and use the common sense: God bless you
It spins, but doesn't pump If your washer spins but doesn't pump the water out, the drain line is probably clogged. In many washers, a small sock or other piece of clothing can get between the clothes tub and the outer tub that holds the water. If the clothing gets between the tubs, it may then get into the drain hose that's attached to the pump--or even into the pump itself. If it's in the pump, you need to remove the hoses from the pump and pull the item out. To remove the sock from the outer tub port, open the washer's main access panel and remove the large-diameter rubber hose that connects the pump to the bottom of the outer tub. Then, using needle-nose pliers, try to grab and remove the clothing through the port. Sometimes you can't remove the stuck clothing from below. Then you have to remove the agitator, top of the outer drum shield, and inner clothes tub. This isn't easy to do--and you may need special tools--so you might be happier getting a qualified appliance repair technician to do the job. If the drain line isn't plugged, the problem may be with your pump. Even if the pump appears to be turning, the internal impeller may be broken. If so, you need to replace the pump. It doesn't spin or pump If your washer doesn't spin or pump water out but the motor is running, your washer probably has a frozen pump pulley. If so, you need to replace the pump. To check the pulley, remove the pump from the washer and try to rotate the pulley manually. If it doesn't turn freely--if it's frozen or stiff--replace it. It pumps, but the water returns If the water that pumps out of the machine goes back into the machine after the spin cycle, your washer may be siphoning the water from a laundry tub that has a slow drain, back into the washer. The usual remedy for this is to improve the draining of the laundry tub. (Is something stuck in the drain?) Also, check for these problems: If the drain hose reaches more than about 4 inches into the laundry tub, cut off the excess. If your drain hose is lower than the washer's cabinet, install an air gap/siphon break assembly.

I it hard to believe that a sink full of water will drain "freely" if the washing machine machine water will not. My suspect is that a minor blockage exists in the main sewer drain line-AFTER the point of connection of the washer. A cleanout point probably exists near that point of connection. Please use it to clear the line.

A washing machine discharges water water at a very high velocity and high capacity. This is far more waste water than the pump was designed to handle. The washer discharge must be connected to what's called an "indirect waste", that is, it must discharge into a laundry tub or sump, so that the excess can be stored until it can be taken by the pump. The specific code that governs this is in chapter 27 of the International Residential Code.

Also in the manufacturers instructions, they allow the discharge from a washing machine ,through an indirect waste. [sic] "The Sanivite is a drain pump that is ideally suitable for use in a basement apartment or anywhere in the house where additional fixtures are most wanted. It will pump waste water away from a variety of sources such as: a kitchen sink, laundry sink, washing machine ***(indirect connection)***, dishwasher, bar sink, etc."

This pump will never be able to handle the discharge directly and you need to provide a receptor to accommodate a washing machine. Is there any possibility of adding a laundry tub adjacent the washer and Sanivite pump?

It sounds more like you have a drain problem that a machine problem. Try draining into the laundry tub and check that the tub drains quickly enough. If not, you have a plumbing problem...Good luck...Nomess

a sink stopper will not damage your unit its to big,,it cant get though your wash basket...check your outlet,,or use another out rated 15 amps or more..

This is a water saver or previously known as a suds saver model. The bottom one is the drain. The top one would go to a suds tub. If you set the machine on save, the wash water is pumped out of the top hose into the holding sink next to the washer. The rinse water goes out the bottom hose to the drain. The next cycle you could set the washer to the very beginning of the main wash cycle and the washer would pump the water from the tub back into the washer to be used as wash water for the second load of laundry. Yea, used water. But the first load would be lightly soiled stuff, and the next load would be old barn clothes or play clothes. It was designed to save water (about 65 gallons used for 2 loads vs. 90 gallons) and soap. (now, front load machines with larger tubs would use as little as 25 gallons for two loads.) Just hook up the bottom hose to the drain. Leave the save / drain switch set to drain and you'll be fine. To be extra safe (in case the switch was accidentally set to save) disconnect the wires at the solenoid where the drain hose splits into two at the back bottom of the washer. (right where the hoses exit the machine.)