Check valve (normally closed) vs. Backwater valve (normally open)

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mbmsv

mbmsv

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It appears that I have a normally closed check valve installed in my house on the main sewer line. Most of the recommendations I've seen are calling for a normally open backwater valve to be used. In one article it even says the following:

Installation of a check valve on your home’s main sewer line is prohibited because it would stop the air circulation needed to vent the plumbing system. “Normally open” valves, which only close in the event of backflow, can be installed in some houses.

Does it make sense? Should I be thinking about replacing the check valve I have with a different type?

Thanks.
 
mbmsv said:
It appears that I have a normally closed check valve installed in my house on the main sewer line. Most of the recommendations I've seen are calling for a normally open backwater valve to be used. In one article it even says the following:

Installation of a check valve on your home’s main sewer line is prohibited because it would stop the air circulation needed to vent the plumbing system. “Normally open” valves, which only close in the event of backflow, can be installed in some houses.

Does it make sense? Should I be thinking about replacing the check valve I have with a different type?

Thanks.
Click to expand...
Well it does sound like what you've pointed out can have some merit. However, just FYI not all Backwater Valves are designed with the flapper open.
Example:Clipboard02.jpg
 
Geofd said:
the correct valve would be a back water valve.....if its accessable and that's in your comfort zone I would change it....
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Well, it's definitely out of my comfort zone and some concrete would need to be broken to be able to do that...
 
Geofd said:
if you know where the other valve is you could saw cut the floor partially break the rest out with a sledge hammer
Click to expand...
I used one similar to the one in the post except I glued short pieces in each end and used 4 band no hub couplings on each end and we built a box so it could removed/and replaced if needed
 
So, I had two plumbers looking at what I have and both said that the current valve is for the storm sewer only and that I don't have a backwater valve for the sanitary sewer at all. I was quoted two different types of a backwater valve: traditional with a mechanical flapper and an Aqua-Protec balloon-type valve. The latter one looks better on "paper" but is it really? Any opinions?
 
mbmsv said:
So, I had two plumbers looking at what I have and both said that the current valve is for the storm sewer only and that I don't have a backwater valve for the sanitary sewer at all. I was quoted two different types of a backwater valve: traditional with a mechanical flapper and an Aqua-Protec balloon-type valve. The latter one looks better on "paper" but is it really? Any opinions?
Click to expand...
do a search on backwater valves....specifically what is a backwater valve used for
 
Geofd said:
do a search on backwater valves....specifically what is a backwater valve used for
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What are you trying to say? I know what it is used for and I've done extensive search. I need to choose between a mechanical valve and a balloon-type.
 
I have absolutely no experience with either type. But after watching the video as to how the balloon type works, I would have to ask the manufacturer, isn't it possible that the discharge line could run FULL due to a possible slowdown(partial blockage down stream for example), thereby closing off the pipe line even though the flow is moving in the correct direction? In other words it can't distinguish direction of flow.
If that was ever the case it would make a bad situation worse.

Just my thoughts. I could be all wet, but I'd have to have the mfr. to convince me otherwise.

Of course we know, or should know that the mechanical type must be maintained and kept clean.
 
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mbmsv said:
What are you trying to say? I know what it is used for and I've done extensive search. I need to choose between a mechanical valve and a balloon-type.
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I put the flapper sytle in my brother inlaws house a couple of years ago.....there was a major stoppage in the street his basement did not flood he opened the cleanout outside of his house and the line was full...he called the town and thery cleared their line and all was good again
 
The balloon type apparently just senses a full pipe and activates the balloon to close off the pipe. However, it does reopen the balloon when it senses the down stream water level receding.
 
Geofd said:
I put the flapper sytle in my brother inlaws house a couple of years ago.....there was a major stoppage in the street his basement did not flood he opened the cleanout outside of his house and the line was full...he called the town and thery cleared their line and all was good again
Click to expand...
Do you know how they found out about the stoppage? There is a danger of self-flooding if the valve is closed but people don't know about it and continue using water. Mechanical valves don't seem to come with alarms. One good thing about this balloon-type valve is that it does come with a sound alarm and it can be easily interfaced to a more advanced alarm unit, which will broadcast over internet I believe. It can also be interfaced to an automatic water shut-off valve, although this stuff is expensive...
 
I'm sure you could find a water sensor system that could be located in a fitting just down stream of a mechanical backwater valve. There seems to be a lot out there.
Just a thought.
 
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Diehard said:
I'm sure you could find a water sensor system that could located in a fitting just down stream of a mechanical backwater valve. There seems to be a lot out there.
Just a thought.
Click to expand...
Not sure where you saw many of such sensors. I have found only one and it is a very basic sound alarm and it depends on a battery. I don't know how loud it is but I doubt I would hear it from a bedroom on the second floor.
 
when there is stoppage in the street the flapper will close and you run the risk of overflowing a fixture.....but you wont get the street backing into your basement yes there are very simple sensors out there
 
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