The washer appears to be operating fine although there seems to be no measurable pressure coming out of the hose. The water sprays but not much force is behind it.

Usually, there are spaces between the pump and head portion of the pump. This space is not sealed and will allow water leaking past the seals to come out. There may be a seal kit available, however I have had better luck just changing out the whole pump. There are many available on ebay. Search for one that will use same mount and hoses. Once the seals are gone, the pump will never be the same (may nickle and dime you the death).

If you are using a water tank for water supply, remove the water supply line from the pressure washer and connect a water hose from a faucet. Turn the water on, then crank the engine. Pull the trigger of the spray gun until water comes out. When then water starts to spray properly the release the trigger, shut engine down with pressure on the line then reconnect the water supply from the tank to the pressure washer. If this fixes the problem then the problem was "air-locked"! Happens alot with new pressure washers that have never been run. If you need any other help, please email me @ [email protected]

Hi,

The reason for "F 20" is that while there is "NO WATER DETECTED ENTERING MACHINE OR PRESSURE SWITCH TRIP NOT DETECTED." If after 30 seconds not minimum 0.1l of water entered or maximum fill time of 13 minutes is exceeded, the valves will be turned off and the error code will be displayed. Press PAUSE/CANCEL twice to clear the display.
The possible fix for this problem is:
If there is no water in the unit: Make sure that both valves at the water source(s) are turned on all the way.
Check for plugged or kinked inlet hoses or plugged screens in the inlet valves.
Verify inlet valve operation.

If there is water in the unit: Verify that the pressure switch hose is in good condition and
properly connected to tub and pressure switch.
1. Unplug washer or disconnect power.
2. Verify there is not a siphon problem.
3. Verify wire harness connections to inlet valves, pressure switch, flow meter, and Central Control Unit (CCU).
4. Check all hoses for possible leaks.
5. Plug in washer or reconnect power.
6. Verify pressure switch operation.
7. Verify flow meter operation by blowing air through the part and measuring the resistance.
8. Verify CCU operation by running a Diagnostic test or any cycle.

Thank you

From the tech sheets on this model, here's what FH means:

If there is no water in the unit:
—Make sure that both valves at the water source(s) are turned
on all the way.
—Check for plugged or kinked inlet hoses or plugged screens in
the inlet valves.
—Verify inlet valve operation.
■ If there is water in the unit:
—Verify drain pump operation.
—Verify that the pressure switch hose is in good condition and
properly connected to tub and pressure switch.
1. Verify there is not a siphon problem.
2. Unplug washer or disconnect power.
3. Verify wire harness connections to inlet valves,
pressure switch, drain pump, flow meter, and
Central Control Unit (CCU).
4. Check all hoses for possible leaks.
5. Plug in washer or reconnect power
6. Verify pressure switch operation.
7. Verify flow meter operation by blowing air through the part and
measuring the resistance.
8. Verify CCU operation by running a Diagnostic test or any cycle.

? If there is no water in the unit: —Make sure that both valves at the water source(s) are turned on all the way. —Check for plugged or kinked inlet hoses or plugged screens in the inlet valves. —Verify inlet valve operation. ? If there is water in the unit: —Verify drain pump operation. —Verify that the pressure switch hose is in good condition and properly connected to tub and pressure switch. 1. Verify there is not a siphon problem. 2. Unplug washer or disconnect power. 3. Verify wire harness connections to inlet valves, pressure switch, drain pump, flow meter, and Central Control Unit (CCU). 4. Check all hoses for possible leaks. 5. Plug in washer or reconnect power 6. Verify pressure switch operation. 7. Verify flow meter operation by blowing air through the part and measuring the resistance. 8. Verify CCU operation by running a Diagnostic test or any cycle.

1. Verify wire harness connections to inlet valves, pressure switch, flow meter, and Central Control Unit (CCU).
2. Check all hoses for possible leaks.
3. Plug in washer or reconnect power.
4. Verify pressure switch operation.
5. Verify flow meter operation by blowing air through the part and measuring the resistance.
6. Verify CCU operation by running a Diagnostic test or any wash cycle.

5 & 6 above are the most likely culprits.

your not missing anything, check the pump, they tend to go bad over time and may need replacing. The pump provides the pressure as well as the suction for the whole process, pulling water from the hose or tank and pushing it forcefully through the pressure washer line. If the motor is running and you have the water going through the line and to the pump, and no water is coming out, my guess would be the pump.

Dear Osville,
It is not clear what type of lance or nozzel you have. You said that the machine works fine with the circulating water jet(the turbo). So it seems the machine is fine. I do sometimes service variable nozzels and variable lances. But the best solution is to replace nozzels and variable nozzles and lances with new ones. Regarding the fan spray setting it could have no pressure because it might be in the chemical setting. The chemical setting lets out a fan shape flow of water, but with less pressure. The chemical system only works on low pressure in domestic washers, that is why it needs a low pressure flat spray. The pencil jet has 2 jets comming out because if it is a lance or nozzel with ball bearings, these ball bearings must have stuck in a wrong position. Also 2 jets can come out, due to a damaged nozzel hole.
Altogether, the best advice is to buy a new nozzel or lance...which ever your machine uses. All Karcher machines have their own specific nozzels, lances and high pressure hoses. You cannot change these from one model to another.
Regards,
Fulltech.

Remove spray tip and clean with a paper clip, Check pump oil resevior and add 10w 30 pump oil if needed, also look for turn knob ,usually black with -+[plus /minus symbols ] and turn towards plus for extra pressure. May need new pistol/wand assembly and make sure hose is clear by seeing if water will run through hose freely and generously.

Thanks odin and please vote me a Fix Ya!!!

JJ505

Check the hose from the tub to the pressure switch, make sure its clear and the reservoir on the tub is clean.