Hammering Check Valve?

[falconut]

I have had my system running for a little over 1-1/2 years. On my return I have a Mag 18 which pumps through a 1" clear double union check valve into two 3/4" return lines.

I the beginning it worked perfect. The power would go out and the check valve would shut. Now when the power goes out, the check valve opens and closes (hammering noise) for a few minutes until it finally closes completely. If I throttle back the ball valve it also closes completely.

I don't believe that any water is getting past the check valve while it's doing this, but I'm confused with this. Does anybody know what could be causing this?

 

[billsreef]

It needs a good cleaning or replacing

 

[BeanAnimal]

make no mistake water is getting past while it does this, at some point it will fail and you will have a flood.

IMHO check valves should be avoided at all costs. In any case as bill said it needs cleaned or replaced.

 

[billsreef]

<a href=showthread.php?s=&postid=7834734#post7834734 target=_blank>Originally posted</a> by BeanAnimal
IMHO check valves should be avoided at all costs.

Personally I like to set my returns up so they are high enough to suck air and break the siphon when the power goes off. I also like large roomy sumps that allow enough water to drain into to them to allow that to happen without overflowing If your going with deep submerged returns, a siphon break can be drilled into the return line just above the water level inside the tank. A 1/4 inch drilled so that it angles down into the tank works well. It still needs periodic cleaning like a check valve, but it's easier to see when it needs cleaning...just keep checking to make it's peeing a nice stream of water If you keep with check valves, they should be taken apart and cleaned every couple of months to keep them from fouling and malfunctioning.

 

[falconut]

I have used siphon breaks and had them clog to many times or simply splash too much. I have 1 return pipe about 3"-4" below the water and the other about 8" below.

I will just take it apart and clean it during my next waterchange. Thanks.

 

[atvdave]

falconut. I also have a check valve that hammers when I shut off the power. It's like they said, it's get dirty.

However I don't relay on the check valve to stop the flow. I use the check valve & the hole for a siphon break together. It's my believe that if the the siphon is too strong that just a little bit of air wont stop it quick enough. So I use the check valve to slow it down.

It works for me.

Dave

 

[Roland Jacques]

check valves in normal config are going to fail sooner rather than later.

the only good way to use a check valve for a aquarium, is to use the check to break the shipon.
this config no water ever goes thur the check valve only air in one direction to break the shipon

 

[Karl K]

good idea, yourfishman

I like the way you think