Hello,

My parents have a problem with either the plumbing or the washing machine. The plumber said it's the washing machine, the washer repair man says it's the plumbing.

When we turn on the outside water spicket or the upstairs bathtub, the washing machine drum fills up with water (even though the washer is off). Both the spicket and tub are higher in elevation than the washer, which is in the lowest part of the house. No other water units cause this issue (another shower, toilets, faucets, etc.) If we shut the water off to the washing machine, then the problem stops, we can turn on the tub or outside spicket and no problem. When you turn the water back on, the drum will fill up when either the tub or spicket are on. To me it would seem that it's the washing machine solenoid valve is not working properly. The water is always on to the washing machine, but its not a problem until you turn on one of those 2 units. As you turn on the tub or spicket, you are reducing the water pressure within the system, which is relieving some of the pressure off the solenoid, would that possibly cause the valve to open?

Does anyone know what might be going on here? The repair man said he has never seen this in 30+ years of repair, and the plumber says there is no issue with the plumbing, its something with the washer.

Thanks,
Steve

Washing machine solenoid valve.

Clothes washer, outside faucet and upstairs tube must be on the same cold water supply. When you open either the outside faucet or the tub cold you reduce the pressure on the cold water line at the washer.
Normally the pressure on the mixing valve of the washer sees equal pressure on both the hot and cold. When you reduce the cold by opening the faucet, the hot water pressure over rides the balancing springs and hot water flows into the washer.

Proof would be to turn off only the hot at the washer to see what happens.

Should be simple replaceement.

At the washer
Hot off/Cold on, water drips into the washer (decently quick, not flowing water though)
Hot on/Cold off, no water drips into washer.

When both are off, there is nothing
When both are on, it will fill up the washer (faster than quick drip/slow flowing water).

Not logical, should be the other way around. Is the water that is going into the washer hot or cold?
Are hoses to washer connected properly, hot to hot and cold to cold?

Do you have separate hose bibs at the wall or is it a washing machine valve (two valves in one body)?

Hot off/Cold on, water drips into the washer (decently quick, not flowing water though)
Hot on/Cold off, no water drips into washer

Sorry could be logical.

Hot off/cold on could be causing leak on hot side because of pressure difference.

Hot on/cold off. Valve would not see a difference in cold pressure.

Regardless, the problem has to be in washer valve since that is the only place the hot and cold come together. Problem is likely to be trash or debris in valve. Should be able to disassemble and clean.