Removing Vacuum Break from Black Flusher (moved from ROO Thread)

[B and B]

Originally Posted by OldCoot

Was deposited in the garbage can. Don't need a vacuum break on a pressure water line and the tank is vented anyway. Works just fine if not better due to getting rid of the 90d elbow.

I agree the back pressure is an issue but this can pose a serious health risk removing the valve. If there is a water pump issue and the pressure drops... you know the rest.

[OldCoot]

Originally Posted by B and B

I agree the back pressure is an issue but this can pose a serious health risk removing the valve. If there is a water pump issue and the pressure drops... you know the rest.

The water pump isn't connected to the black tank flush in any manner. They are 2 completely separate systems.

[B and B]

Originally Posted by OldCoot

The water pump isn't connected to the black tank flush in any manner. They are 2 completely separate systems.

The water pump that provides pressurized city style water. I am aware they water pump in the trailer does not run the black flush.

My local park water system had a power failure and it sucked someones homemade black flush back into the system, no pressure break. Was polluted for several weeks. The guy was asked to remove his trailer from the park the following week, had been there for 20 years with this illegal and unsafe setup.

[OldCoot]

Originally Posted by B and B

The water pump that provides pressurized city style water. I am aware they water pump in the trailer does not run the black flush.

My local park water system had a power failure and it sucked someones homemade black flush back into the system, no pressure break. Was polluted for several weeks. The guy was asked to remove his trailer from the park the following week, had been there for 20 years with this illegal and unsafe setup.

He must of had a fresh water hose connected to the black tank flush and had the faucet open. No hose connected unless flushing on mine. I think in your example something is missing more than the lack of a pressure break. Like I said before, they are two separate systems and not connected in any way.

[bubbles]

Originally Posted by B and B

The water pump that provides pressurized city style water. I am aware they water pump in the trailer does not run the black flush.

My local park water system had a power failure and it sucked someones homemade black flush back into the system, no pressure break. Was polluted for several weeks. The guy was asked to remove his trailer from the park the following week, had been there for 20 years with this illegal and unsafe setup.

Old Coot is correct on this one. If that individual created his own flush system and it caused issues he did something very strange. We need Paul Harvey. Here is the typical factory install clean out system. It is an independent isolated system unto itself. I think the vacuum breaker/backflow preventer (vbbp) is overkill with the way the tubing is routed in our type of environment (rv's). Old Coot eliminated a lot of tubing and the vbbp shown but he does have a check valve at the input port for his cleanout. JMO

[B and B]

Agreed, water pressure that provides the inability for return flow. It can happen, has in a small town in Ontario 7 People died due to Ecoli contamination of a municipal water supply, I am just playing the safe card here. a external pressure break could be used.

[B and B]

Originally Posted by bubbles

Old Coot is correct on this one. If that individual created his own flush system and it caused issues he did something very strange. We need Paul Harvey. Here is the typical factory install clean out system. It is an independent isolated system unto itself. I think the vacuum breaker/backflow preventer (vbbp) is overkill with the way the tubing is routed in our type of environment (rv's). Old Coot eliminated a lot of tubing and the vbbp shown but he does have a check valve at the input port for his cleanout. JMO

It is against code RVIA and just about any municipality

From RVIA

Plumbing Systems as specified in NFPA 1192 Standard for RVs.
Only listed plumbing devices, fixtures and appliances that have been labeled by nationally recognized testing agencies are allowed.
Water distribution systems are sized to provide adequate flow rate and designed to prevent backflow contamination.
Fixtures with traps and vents must be provided to protect against siphonage and back pressure.
Vents to release gases from any waste holding tank must be provided.

Check Valve is a modification to a code requirement. A step but not replacement for the Vacuum Breaker.

[OldCoot]

Originally Posted by B and B

It is against code RVIA and just about any municipality...Check Valve is a modification to a code requirement. A step but not replacement for the Vacuum Breaker.

JMO, but I think you are comparing apples to oranges. The black tank is vented thru the roof. The backflow preventer I removed was a duplicate as I already had a factory installed backflow preventer at the hose inlet as shown in the picture.

[Broadway Joe]

Originally Posted by B and B

It is against code RVIA and just about any municipality

From RVIA

Plumbing Systems as specified in NFPA 1192 Standard for RVs.
Only listed plumbing devices, fixtures and appliances that have been labeled by nationally recognized testing agencies are allowed.
Water distribution systems are sized to provide adequate flow rate and designed to prevent backflow contamination.
Fixtures with traps and vents must be provided to protect against siphonage and back pressure.
Vents to release gases from any waste holding tank must be provided.

Check Valve is a modification to a code requirement. A step but not replacement for the Vacuum Breaker.

Then my camco black tank flush your saying is illegal? It is hooked up exactly as Old Coot has suggested and per the Manufacturers instruction.

[B and B]

Originally Posted by OldCoot

JMO, but I think you are comparing apples to oranges. The black tank is vented thru the roof. The backflow preventer I removed was a duplicate as I already had a factory installed backflow preventer at the hose inlet as shown in the picture.

You are legal then, I will do the same when mine fails.

[Telstar]

Thats exactly how my Cardinsl is plummed. The nackflow prventor on mine is accessable behind the shower valve. I replaced my sprayer with the rotating one available at Camping World, works much better.

[bubbles]

Originally Posted by B and B

It is against code RVIA and just about any municipality

From RVIA

Plumbing Systems as specified in NFPA 1192 Standard for RVs.
Only listed plumbing devices, fixtures and appliances that have been labeled by nationally recognized testing agencies are allowed.
Water distribution systems are sized to provide adequate flow rate and designed to prevent backflow contamination.
Fixtures with traps and vents must be provided to protect against siphonage and back pressure.
Vents to release gases from any waste holding tank must be provided.

Check Valve is a modification to a code requirement. A step but not replacement for the Vacuum Breaker.

Never said there was no code for the install of these systems. It is in fact referenced on the document I posted. I just said that because of the routing of the tubing in my RV cleanout, in my opinion, the backflow preventer is an over kill. It's just an opinion and everyone has one of those. The cleanout is only used when emptying the tank and it's empty when finished and I cannot see how any backflow from an empty tank can get to the input spigot where pressure was previously applied. That's all.

[itat]

Suffice to say a backflow preventer is required by code. If it wasn't, FR wouldn't install it. There is a direct connection between the black tank and the campground's potable water supply system so the water supply system has to be protected from contamination.

I use an external brass one like the picture B & B posted because the original owner of my TT removed the factory version.

[B and B]

This does happen in real life.

Google Walkerton Ontario...

7 dead due to Ecoli...same as missing back flow preventer can cause.

When this is removed it creates a hazard for others. If you choose to do something like remove your LPG protectors that is more or less a hazard for you unless the trailer blows up and sends shards of metal at your neighbours.

[B and B]

Originally Posted by OldCoot

The water pump isn't connected to the black tank flush in any manner. They are 2 completely separate systems.

Doing this Tomorrow!!

[stephndudb]

Originally Posted by bubbles

The cleanout is only used when emptying the tank and it's empty when finished and I cannot see how any backflow from an empty tank can get to the input spigot

We've all heard the stories of people who forget to open their black tank gate valve before using the flusher, or use the flusher to partly fill the black tank to get a better rinse then forget to open the gate valve soon enough. That's how contaminated water can reach the level of the sprayer and, from there, the hose.

Let's say you accidentally ran the flusher with the gate valve closed and partially filled the tank. Then you disconnected the hose from the campground spigot. Gravity/siphon would pull the contaminated water out of the tank and into your hose as you disconnect, maybe reaching the spigot where the next person will be connecting. Not likely, but I'll bet someone's done it somewhere. Would prefer it not to be a campground I'm staying in or the next spigot I'm going to connect my fresh water hose to.

I agree the vacuum breaker sucks. If you get rid of it, please add an external brass backflow preventer like the one pictured between your rig and the campground spigot.

[bubbles]

Originally Posted by stephndudb

Let's say you accidentally ran the flusher with the gate valve closed and partially filled the tank. Then you disconnected the hose from the campground spigot. Gravity/siphon would pull the contaminated water out of the tank and into your hose as you disconnect, maybe reaching the spigot.

This is an old thread and from this post you really do not know how the back flow/check valve functions.

[stephndudb]

Originally Posted by bubbles

This is an old thread and from this post you really do not know how the back flow/check valve functions.

Ok. Please explain.