Attic tank overflows when powerwashing

spuddy4711

Connected power washer to kitchen cold mixer tap. Works fine on Eco but cycles on/off every few seconds if I try to use full power. Figured lack of flow from the mains, so turned on hot side also. Full power from power washer, but after 30 minutes the attic tank began to overflow. Mystified.

jhegarty

Your hot side should have a non-return on it. The pressure is pushing it back that side.

mloc123

spuddy4711 wrote: »

Connected power washer to kitchen cold mixer tap. Works fine on Eco but cycles on/off every few seconds if I try to use full power. Figured lack of flow from the mains, so turned on hot side also. Full power from power washer, but after 30 minutes the attic tank began to overflow. Mystified.

You are back pumping mains water into the hot water tank....

By connecting the mains cold water and hot water (when you open both and have a connector on the tap you are basically bridging both feeds)... the mains pressure is higher than the hot water pressure and it is then feeding water to the hot tank via the hot water tap pipe.

the_pen_turner

Its strange that this is improving the power washer.
If you run the hose not conected are you getting high pressure then low pressure. That could explain it . The tank is evening it out

spuddy4711

Many thanks, folks, penny has dropped, I’ll stick with Eco.

standardg60

The water tank initially provided enough pressure gravity wise to flow to the tap, but as it emptied the pressure flow was reversed.

OP your mains pressure doesn't provide enough flow directly to the washer, fill a wheelie bin first and then drop the washer feeder hose into that.

spuddy4711

Will try try the bin tomorrow and report back, thanks for all your info. Appreciated.

spuddy4711

Siphoning from wheelie bin worked a charm, full power from washer. From mystified to delighted.

And a spotless wheelie, thanks to all.