Community Forums

Bob108 · 03-08-2025, 07:00 AM

2020 New Aire 3545 new to me/first trip. Went to flush black tank, no flow out sewar hose. Heard water flow. Flooded bottom of coach. Any thoughts? TIA

**hamm2018** · 03-08-2025, 07:05 AM

Check the hose from the outside to the tank flush and make sure it is connected.

TonyMac · 03-08-2025, 07:36 AM

"Flooded bottom of coach. Any thoughts?"

Inside the coack or inside the compartment?

My black tank flusher flows into the coach under the bath vanity. Therein, is the air lock and the check valve. It then flows back thru the floor, into the wet bay, and enters the black tank on the curb side of the black tank in wet bay. It was plugged solid when I got this rig. There are a bunck of connections, seems one of yours has come apart.

LETMGROW · 03-08-2025, 07:58 AM

Quote:

Originally Posted by TonyMac

"Flooded bottom of coach. Any thoughts?"

Inside the coack or inside the compartment?

My black tank flusher flows into the coach under the bath vanity. Therein, is the air lock and the check valve. It then flows back thru the floor, into the wet bay, and enters the black tank on the curb side of the black tank in wet bay. It was plugged solid when I got this rig. There are a bunck of connections, seems one of yours has come apart.

Why do these RV builders complicate things? Wouldn't a drain on the bottom of the black tank suffice? That's the way mine is built. I hook up my drain hose and pull the handle to open the drain and "Whoosh". Within a couple minutes the tank is emptied. Sometimes simpler is better.

workingonit · 03-08-2025, 08:00 AM

How do you flush it?

**hamm2018** · 03-08-2025, 08:04 AM

Quote:

Originally Posted by workingonit

How do you flush it?

I haven't flushed the black tank since we purchased the rig in October 2017. We full time, so we dump at least once a week.

Kevin Bell · 03-08-2025, 08:07 AM

Quote:

Originally Posted by Bob108

2020 New Aire 3545 new to me/first trip. Went to flush black tank, no flow out sewar hose. Heard water flow. Flooded bottom of coach. Any thoughts? TIA

"Flooded bottom of coach" - if this means under the coach, the black tank rinse low point drain is probably open, see diagram.

Bob108 · 03-08-2025, 05:43 PM

Thanks for all the input. I wish it was under the coach. In the basement/storage
area.

followingsea · 03-08-2025, 06:04 PM

Quote:

Originally Posted by Bob108

2020 New Aire 3545 new to me/first trip. Went to flush black tank, no flow out sewar hose. Heard water flow. Flooded bottom of coach. Any thoughts? TIA

Are you flushing or draining?

Why would flush a black tank?

Kevin Bell · 03-09-2025, 06:21 AM

Quote:

Originally Posted by Bob108

Thanks for all the input. I wish it was under the coach. In the basement/storage
area.

Leak into the plumbing bay would indicate a failed connection or component on the flush line. If water presented above floor line, I would suspect the vacuum breaker/check valve. Plumbing inspection behind service panel is the only way to determine failure.

workingonit · 03-09-2025, 06:25 AM

Quote:

Originally Posted by followingsea

Are you flushing or draining?

Why would flush a black tank?

To get the crap out of the tank that won't run out on it's own. My RV has a black tank flush that a hose connects to and water can be sprayed in the tank to flush. I keep a hose on it all the time when we are connected.

Bob108 · 03-09-2025, 08:51 AM

Used air to try and locate leak. Appears to be behind central vacuum above transfer switch. Now I'm unable to get power on coach.

Bob108 · 03-13-2025, 06:17 AM

Quote:

Originally Posted by TonyMac

"Flooded bottom of coach. Any thoughts?"

Inside the coack or inside the compartment?

My black tank flusher flows into the coach under the bath vanity. Therein, is the air lock and the check valve. It then flows back thru the floor, into the wet bay, and enters the black tank on the curb side of the black tank in wet bay. It was plugged solid when I got this rig. There are a bunck of connections, seems one of yours has come apart.

Great Information. My leak is where the lines travel thru floor to vanity. No water in bathroom. Wonder if I could move air lock / check valve, lower, below floor to get system back. Leak was above Transfer Switch which is fried.

followingsea · 03-13-2025, 02:51 PM

Quote:

Originally Posted by workingonit

To get the crap out of the tank that won't run out on it's own. My RV has a black tank flush that a hose connects to and water can be sprayed in the tank to flush. I keep a hose on it all the time when we are connected.

My MH has a flush connection. I have never used it. It is an accident waiting to happen.

This one of many features RV manufactures provide that are really bad. It sounds good in advertising brochures but bad in proactive.

I am full time. Never have a problem with odor or completely draining the black water tank.

Here is my best proactive. First I put enough water in an empty tank while I have access to water so that any solids are covered with water.

Then I only dump a tank when it is at least 2/3 full. That is anywhere from once a week to 6 weeks. This ensures that there is enough water water velocity to carry all solids out.

After flushing the black tank, I use the grey water to flush the hoses.