Washerhelp
#2. October 24th, 2007, at 2:24 PM.

I know you wouldn’t ask if it wasn’t something you felt you needed to explore but I would be extremely surprised if anyone made a stacking frame which allowed a dishwasher to sit on top of a washing machine.

If the dishwasher leaked it could potentially soak the washing machine beneath and cause physical and or electrical damage.

Dishwashers also tend to be a different shape and depth than a tumble dryer which tends to be quite similar to a washing machine so the dishwasher is likely to be a poor physical fit.

The biggest problem is that the drain hose for the dishwasher would be far too low because the plumbing would be a few feet beneath it. This could allow water to siphon out during use causing the dishwasher to malfunction as this washing machine troubleshooting section describes -constantly fills with water and goes down the drain

Washerhelp
#4. September 10th, 2008, at 3:26 PM.

That’s an interesting idea. I’m not aware of anything available to do that. There’s no way a washing machine / tumble dryer stacking kit would be suitable because of the difference in shape and size of the appliances.

If you just stacked the fridge on top of a freezer, in theory (if it was a stable fit) they could be OK because they don’t move or bounce around. However, there would be a danger of the top appliance being knocked off. The arrangement would be particularly unstable when the door of the top appliance was opened as any leverage on the door could topple it on top of someone. Also, if the door was opened but then closed again and you tried to open it again shortly after then the door tends to be extra hard to open as it creates a type of vacuum. This could also cause the top appliance to fall off if someone pulled on the door but it didn’t open and instead pulled the appliance forward.

Having said all that, I have this arrangement in my garage where I have a free standing upright freezer with a free standing fridge on top. The freezer is slightly larger so the fridge stands firmly on top without the feet being precariously close to the edge. Everything works fine and feels stable.

Washerhelp
#6. September 30th, 2008, at 11:50 AM.

Jose: The main issue apart from stabiity and leaks is the drain hose. A drain hose on a washing machine or dishwasher needs to go up well above the level of the water inside the machine to prevent siphoning.

The waste water pipe is usually near floor level and extends 2 - 3 feet up the wall where the drain hose is then placed. To position the waste water pipe in the correct position for a machine elevated 3 or 4 feet high it would need to be similarly elevated which depending on the siting could be undesirable. On the other side of the wall the pipework would run outside at about 5 feet above ground and would look similarly bad.

Personally I feel it’s a bad idea. Have you looked into having one fitted into a kitchen cupboard. You can get built in dishwashers that take up just one cupboad space or small dishwashers - or even worktop dishwashers that drain into the sink. You could regain the cupboard space by having one fitted above the washing machine.

Washerhelp
#8. September 30th, 2008, at 1:47 PM.

Jose: If the drain hose was extended so it was long enough to be tied up at the back of the dishwasher but then run into the sink it might avoid the siphoning problem. If the drain hose just runs downwards to the drain or as in your case to the sink then because the water inside the appliance is higher than the end of the drain hose it can just run out through gravity.

If the drain hose is forced to go up first, then is allowed to drop lower then water should only run into the sink if it was pumped up 3 feet or so before running down to the sink.

However, if the end of the drain hose is lower than the level of water inside the appliance it is possible for siphoning to occur because the pump can start off siphoning in the same way as you could by suckig the end of the hose. Once water has started to run down a pipe it will continue even after the pressure that started it has gone (this is what we call siphoning). It would depend exactly how the appliance works. If the machine started filling whilst water was still running out of the machine (if siphoning has been started) it is possible under the circumstances we are discussing that water would run into the machine but go straight down the drain and the appliance would be stuck in a never ending filling and draining cycle.

You would only know for sure after trying it out.

[ related: Washing machine constantly fills with water and goes down the drain ]

Washerhelp
#10. September 30th, 2008, at 3:45 PM.

You would need to double check if looking into a worktop dishwasher. They are very small though so possibly unsuitable. I can’t say for sure, but I think they may not have a normal pump, I think they may have a valve that opens up when it needs to drain using the wash motor. I know dishwashers from the past used to have this arrangement until modern dishwashers started to have a separate pump similar to a washing machine pump.

As worktop dishwashers are designed to sit on a worktop and many will pressumably drain into the sink at the side I suspect they may have the drain valve instead of a pump, which would not allow any water out of the machine unless the machine was wanting to drain.

No one should assume this is the case though and should check they are suitable for draining into the sink.