Shurflo Extreme 4.0 Water pump

[plongson]

I don't know if anyone here has had trouble getting one of these pumps to run when installed in a retrofit situation but I did and I wanted to let you know what I found out to get it to run.



First the dilemma: Remove the old Shurflo contactor style pump, install the new controller style pump, new pump WON'T run. got 12. 8v... old one runs, new one won't. BUT IT WILL RUN WHEN CONNECTED TO A BATTERY. It will NOT run when connected to a FILTERED power output from the AC converter, and this is the way all the outputs are configured. YOU NEED UNFILTERED DC POWER.



Turns out the modified DC signal coming from the AC converter is so bad that the electronics in the new controller style pumps will not even think they are powered up!



You should have extra lugs on your converter that are essentially a direct link to the battery and not mearly an 12v output from the converter.



I nearly pulled out my hair before I got this one straighted out.



Just a little heads up... file this info away...



Click to see shurflo pump

 

[TowPro]

Another reason I love my Progressive Dynamics charger. They are clean output. In fact I have run my Ham radio off it in the past. Plus if you use the charge wizard no more over charged boiled out batteries.

 

[dodgeguy44]

I had a Smart Sensor 5. 7 installed in our 5th whl about a year ago and I know I can p#@@ more pressure in my shower now. The dealer said the stock pump was no good but it put out way more pressure and volume.



I have fought with the dealer about this ever since, so tomorrow I am going to check your theory with a jumper wire and if it works I'll owe you big time. I have checked the voltage and it stays up with the battery.



I'll let you know.

 

[rweis]

I bet it would run on a Progressive Dynamics converter, and their Charge Wizard is the very best battery charger system possible.



Bob Weis

 

[plongson]

I had a Smart Sensor 5. 7 installed in our 5th whl about a year ago and I know I can p#@@ more pressure in my shower now. The dealer said the stock pump was no good but it put out way more pressure and volume.



I have fought with the dealer about this ever since, so tomorrow I am going to check your theory with a jumper wire and if it works I'll owe you big time. I have checked the voltage and it stays up with the battery.



I'll let you know.

I originally bought this Shurflo Smart Sensor 4. 0 pump for another project and decided to install it in the TT because it worked so good.



My Shurflo Smart Sensor 4. 0 performs very similar to what you are describing, low flow and low pressure as compared to the old 2. 8 contactor style Shurflo. It is REALLY disappointing considering the cost to replace these pumps and how poorly they perform when installed in a RV.



I did some testing…



Scenario: Direct connect to a full 13. 5vdc supply. (2-Trojan T-105’s).

Pull water from a neutral level supply. (no lift, no drop)

Pump directly into a container. (no head, no drop)



This is a very fair test...



The old 2. 8 gpm pump put out 2. 2gpm. Cut-off at 50psi and Cut-in at 30psi

The new 4. 0 put out 3. 2gpm. Cut-off at 50psi and Cut-in is variable speed but starts with a very slight pressure drop and runs full speed somewhere below 10-15psi.



The flow is not what it is rated, but I understand marketing and realize “Your results may differ” excuse, but the pump is actually putting out more water on the bench than the little pump.



In the trailer it is a TOTALLY different story and something else to consider.



These controller style pumps are very sensitive to upstream pressure. This is how they vary their speed. They are not simply “ON and OFF” contactor style. When they see a slight drop back-pressure they run slow thinking the demand is low. When there is no back-pressure they run full speed thinking the demand is high. My pump performed perfectly in my test.



This is where it gets messed up…The RV piping, actually relatively small plastic tubing will not EFFICIENTLY carry the volume of water that these pumps are rated to put out. The result is system BACK-PRESSURE and this is what is killing us. The RV plumbing is not sized to carry the amount of water these pumps are putting out. The lines are too small and the result is a poor performing system. It is not the pumps fault, it is not the trailers fault, and we just want too much water from a small system. There are really no options as I can see.



Try this test yourself. Turn on the pump. Open several faucets including the shower. Listen to the pump. It probably running slow to about half speed. Shut off the pump switch and let the pressure bleed off. Flip the pump switch back on. The pump should run at FULL speed until the faucets are closed.



This pretty much verifies the pump is good and the system has restriction.



Let my know what you guys find out…

 

[TowPro]

I put a "T" in the water line just after my water pump (outlet side) that has a hose style fitting. From there I ran a washing machine hose up to a small pressure tank. Its a little bigger then a 1 gallon jug. I found this tank in Lows between the plumbing and heating section. Its a rubber membrane tank with a valve stem to adjust the pressure.



Works wonders on the RV water system. Its good for a couple flushes. Just besure to "T" it in close to the pump and run a bigger hose to the tank then the RV uses. If you don't the pump will stutter when you flush.



In the winter I leave it connected. I winterize using a "T" kit and the pump. Just remember to open a valve and let all the pressure off the system when your done, and the pressure tank will be empty because of the pressure behind the membrane.

 

[dodgeguy44]

update

I finally plumbed in a pressure gauge, which I should have done earlier on, and the pump only put out 32 psi. I called Shurflo, because they don't answer e-mails I guess, and talked to Pedro. He told me to take it to Camping World in Tucson and have it replaced. We were set up in a Park so I removed it myself and took it in and they handed my a new one. I went back and installed the pump, 62 psi. Great!



He also told me to remove the accumulator and any elbows at the pump outlet. It is recommended to have at least 18 inches of flexible water line between the pump and the PEX hose used within the coach.



I really enjoy the shower now! It's great to get such excellent warrantee service on a defective product and I congratulate Shurflo.