Air in system... HELP!!

afairs · 09-14-2016, 11:46 PM

Hey guys, Canadian asking for help!!

I have a 2012 33ft Forest river. After the water system sits for 45minutes are more the entire system needs to be "re bled". After sitting for a hour or more, the waterpump will turn on and not shut off... just cycling air until I turn a tap on to let water through. I have just installed 2 brand new pumps, same issue with all 3 pumps. I installed a 1-way valve on the inlet of the water pump to help any "bleed off" issues. That did nothing...

Since water can not leave the pump and go back to the tank, it must be bleeding off after the waterpump? I dont understand how air is entering the system. Water tank is full, inside and outside showers are turned off. Its not the toilet... I am out of ideas!

Bluepill · 09-15-2016, 12:36 AM

I would look for leaks anywhere the plumbing runs. You could be damaging the structure if you have one. Follow the lines. The water heater area would be a possible leak area with the winterizing valves nearby.

If you find nothing obvious, you can pinch off the supply hoses to different runs (sections) and see if that stops the pressure drop.

Don't forget to check the TP relief valve on the water heater, as well as looking under the RV for any wet spots.

The constant vibration when driving an RV creates many more potential problems than a fixed installation like a home.

afairs · 09-15-2016, 12:43 AM

No wet spots anywhere. Pinching off the lines sounds great but they plumbed my entire rv with those red and blue pvc lines, cant pinch them. And the winterize thing you are mentioning... I dont have access to behind my water-heater, it seems like they build the trailer around it! I'll dig in and take a better look tomorrow in the sunlight. Why would a rv hot water heater winterizing valve cause air? just a valve isnt it?

Witch Doctor · 09-15-2016, 06:13 AM

The only place that is going to supply water to the pump is from your fresh water tank, either your sucking air from that line or from your over flow, depending on where your out let is cut into the tank. make sure that the strainer on the tank is tight, even use some plumbers tape on the treads, I f your on a 3rd pump and it is still doing the same thing it would have to between your fresh water tank and the pump....

put that up for you...

PS what model FR 2012 do you own, there must be a access panel somewhere to get the valves to winterize you might as well find it now, that's why I ask only. There are three valves that are going to have to be turned hooked to that tank, unless it is tankless.

afairs · 09-15-2016, 10:41 AM

2012 268 RLDS Coachman Chaparral. From my understanding this is a Forest river product since Coachman went bankrupt in 2008.

**Bama Rambler** · 09-15-2016, 11:35 AM

You turn on the pump and it will not pump up pressure and shut off unless you bleed the air out of the system. Is that correct?

Once the system is up to pressure, you shut the pump off, and after a few minutes it has air in it again. Is that correct?

Once you bleed the air out of the system, what happens if you draw a glass of water? Does it have air bubbles in it?

About the only way air can get into the system while it's pressurized is if there's a leak on the suction side of the pump. If the system is fully depressurizing after you turn the pump off, you have a leak somewhere, and you really need to find it.

If you turn the pump off and turn it right back on does it immediately start running?

If you leave the pump switch on, how often does it cycle on and off automatically?

**bikendan** · 09-15-2016, 12:36 PM

Quote:

Originally Posted by afairs

2012 268 RLDS Coachman Chaparral. From my understanding this is a Forest river product since Coachman went bankrupt in 2008.

Coachmen is a separate division of FR.
FR is the umbrella corporation so there is no actual FR brand RV.
I believe FR acquired Coachmen before it went bankrupt.

afairs · 09-15-2016, 01:44 PM

Quote:

Originally Posted by Bama Rambler

You turn on the pump and it will not pump up pressure and shut off unless you bleed the air out of the system. Is that correct?

Once the system is up to pressure, you shut the pump off, and after a few minutes it has air in it again. Is that correct?

Once you bleed the air out of the system, what happens if you draw a glass of water? Does it have air bubbles in it?

About the only way air can get into the system while it's pressurized is if there's a leak on the suction side of the pump. If the system is fully depressurizing after you turn the pump off, you have a leak somewhere, and you really need to find it.

If you turn the pump off and turn it right back on does it immediately start running?

If you leave the pump switch on, how often does it cycle on and off automatically?

Yes to everything except the bottom two questions. Once it has pressure, I can turn the switch on and off and the pump will stay off. But say after 10 minutes or so it will prime itself again. If I wait longer, it will just run and run and run.

If I leave the switch on, the pump will stay off once primed. But usually after an hour, it'll turn on and just stay running... Usually most pumps will cycle to build up pressure. All of mine will now have air and continually run.

**Bama Rambler** · 09-15-2016, 02:36 PM

Once you turn the pump off, how long does it take before you can't get any water out of a faucet without turning the pump on?

If I'm correct, you have a small air leak in the suction side of the pump somewhere between the pump and fresh water tank. Once you find and fix that leak, you're problem will be fixed.

It may be a pinhole in a line or a leak at a fitting. Since that side is not under pressure, it's probably not leaking any water out.

Steveboe · 09-15-2016, 03:02 PM

Since you are familiar with your water pump and fittings, why not try to put a line on the suction side of the pump and drop the other end of the line in a bucket of water. If the problem goes away, then you know that you have a suction leak on that side of the pump.

afairs · 09-16-2016, 02:55 PM

I have narrowed things down. I ran a hose directly to the pump and into a bucket of water and to the interior plumbing. Absolutely no air! I ran the bucket into the main water system (through the exterior valves) and than it had air... so I bypassed the exterior valves and ran the water pump from the holding tank directly to the interior plumbing and there was no air.

Turns out, the valves on the outside of the trailer are somehow introducing air. The valves say fill/winter and main/winter or something along those lines. The valves are not leaking... but introducing air. This is on the pressurised side of the system.

afairs · 10-06-2016, 11:59 PM

Just as an update, It turned out to be the 2 valves in the exterior "service box" that where sucking in air but not leaking water. I replaced them with brass valves instead of plastic and problem is solved! I have since installed a water hammer, insulated all of my piping and installed an adjustable pressure regulator.

Lefty59 · 10-07-2016, 12:22 AM

Sounds like at least one of those valves was the valve to switch the water pump to draw antifreeze during the winterization process. I have two valves that are utilized when winterizing my Wildcat. One valve bypasses the water heater and the other valve allows the water pump to draw antifreeze from a hose in the service area.

I have accidentally left the winterization valve for drawing antifreeze into the water pump in the wrong position in the spring and had the water pump sucking air like you describe. It was a head scratcher for a moment or two until I realized the valve was set incorrectly for the regular use of the water pump.

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