Check Valve

[ca1ore]

I think most experienced reefkeepers don't use check valves; I know I have many of them languishing in my plumbing odds and ends drawer (some 25 years old). They are NOT a good solution to prevent a back siphon overflow of the sump, but they can be helpful in preventing that massive, initial back siphon rush.

This came up recently for me because when there is a brief power interruption on my system, the large back flow through my main pump (tank is on the first floor, sump in the basement so the back siphon is significant) turns the impeller backwards and the pump won't restart properly. If I was not home to power cycle the pump it may well have burned itself out. I have adjusted my apex programming to delay the restart of the main pump if there is a power interruption so that the back siphon completes before the pump attempts to restart; but I have also considered adding an oversized check valve on the suction side of the pump to help to prevent back spinning of the impeller. Oversized is key, as you never want to add resistance to the input of a pump.

Curious if anyone has done this? If anyone thinks it's a bad idea, don't just say its a bad idea, please explain your logic.

 

[jsker]

I put a check value in place. I was told not to, but did I listen. The one I used can be cleaned. The flapper one is were I was seeing issues I also have a drain and overflow installed in my sump.

 

[ReefHog]

Not sure what a check would do on the suction side that it would not do on the discharge side. Agreed that check valves can not be relied on to stop 100% of the back flow in a power outage. But as you mentioned, one would surly stop the massive rush of water. Have you considered a reverse check valve set up? This is what I use and works like a charm.

 

[mfinn]

I think most experienced reefkeepers don't use check valves; I know I have many of them languishing in my plumbing odds and ends drawer (some 25 years old). They are NOT a good solution to prevent a back siphon overflow of the sump, but they can be helpful in preventing that massive, initial back siphon rush.

This came up recently for me because when there is a brief power interruption on my system, the large back flow through my main pump (tank is on the first floor, sump in the basement so the back siphon is significant) turns the impeller backwards and the pump won't restart properly. If I was not home to power cycle the pump it may well have burned itself out. I have adjusted my apex programming to delay the restart of the main pump if there is a power interruption so that the back siphon completes before the pump attempts to restart; but I have also considered adding an oversized check valve on the suction side of the pump to help to prevent back spinning of the impeller. Oversized is key, as you never want to add resistance to the input of a pump.

Curious if anyone has done this? If anyone thinks it's a bad idea, don't just say its a bad idea, please explain your logic.

If you are going to use a check valve, why not just use it on the return side and use the same size as the plumbing?
Are you thinking it may be a benefit to add it to the suction side?
I understand why you want to use it. I use one too on my 233. I use it to prevent my skimmer overflowing ( if I forget to remove the cup when it's full ) when I shut off the return pump for water changes. My sump can handle the volume of water before the siphon breaks.
I use the wye check valve. It's pretty easy to clean out.

 

[Brew12]

My biggest concern with it on the suction side of the pump is that you may get larger pieces of debris in it. At least on the return side there is a chance the impeller would tear it up a little.

I use a check valve with unions and keep a spare. That way I can swap them out easily for cleaning without keeping the tank down longer.

 

[ca1ore]

If you are going to use a check valve, why not just use it on the return side and use the same size as the plumbing?
Are you thinking it may be a benefit to add it to the suction side?

I haven't given it a ton of thought. Was looking for a way to service the thing easily and not have to take my current plumbing apart (though the flow sensor needs cleaning every few months so may be not a biggie after all). Also trying to avoid water hammer, which I can do by attaching the check to a run of silicone tubing (though the suction might collapse it). I don't trust that tubing on the pressure side given how high I'm pumping the return water. I generally preferred the flappers to the Y checks, not quite as much whack when it closes.

 

[Doclight]

I do the same. I run a check valve attached to unions, so if it ever fails, out it goes. Some don't like them, I figure it can't hurt. If it fails, then its really no different then not having one at all.. But if it works, then you just saved your floors!

 

[MaddyP]

I think most experienced reefkeepers don't use check valves; I know I have many of them languishing in my plumbing odds and ends drawer (some 25 years old). They are NOT a good solution to prevent a back siphon overflow of the sump, but they can be helpful in preventing that massive, initial back siphon rush.

This came up recently for me because when there is a brief power interruption on my system, the large back flow through my main pump (tank is on the first floor, sump in the basement so the back siphon is significant) turns the impeller backwards and the pump won't restart properly. If I was not home to power cycle the pump it may well have burned itself out. I have adjusted my apex programming to delay the restart of the main pump if there is a power interruption so that the back siphon completes before the pump attempts to restart; but I have also considered adding an oversized check valve on the suction side of the pump to help to prevent back spinning of the impeller. Oversized is key, as you never want to add resistance to the input of a pump.

Curious if anyone has done this? If anyone thinks it's a bad idea, don't just say its a bad idea, please explain your logic.

Yes, I had the same issue on my 400g build. Check valves slowed the flow enough so the return pumps could come back on properly after a power failure. In this case, the check valve isn’t a safety feature which might fail at some point, it serves another purpose.

 

[mfinn]

I generally preferred the flappers to the Y checks, not quite as much whack when it closes.

At first it kind of bothered me, but then I realized that when I heard it hit, I knew it had stopped the water flow.

 

[ca1ore]

Yes, I had the same issue on my 400g build. Check valves slowed the flow enough so the return pumps could come back on properly after a power failure. In this case, the check valve isn’t a safety feature which might fail at some point, it serves another purpose.

If the power outage is just a flicker, no problem. If it's more than a few minutes, also no problem. It's just for that 1-2 minute outage ..... that doesn't happen very often. Been reluctant to put in a check valve because ive tried to squeeze every gallon out of my pump and it will just add back pressure.