2 check valves together?

r6justin · 01/21/2014, 03:01 PM

as we all know check valves eventually leak. About every year I replace mine with a new one, and im thinking about running 2 right after each other. would this work, or not?

1. the flap is usually partially open and if valve 1 is shut but slowly leaks, valve 2 wouldn't have enough flow to close it.

2. or would valve 1 close, and leak, then fill valve2 and when water level hits the valve it will close and then would have enough pressure.

3. or would they both close at the same time and both be locked shut, since water was flowing to both and when the pump stops the water between the 2 valves would stop valve 2 and tank pressure would stop valve 1. since this is an air lock shouldn't the back pressure close both anyway because of the water draining down the hose?

This is on my 150 with a bulkhead on bottom of tank flowing to sump.

davocean · 01/21/2014, 04:24 PM

Sounds like double the headache to me, can you cap that bulk on the bottom and drill a new one where it should go?
It would be more reliable and less headaches in the long run than what you are trying to do, which could just double the chance of a failure.
I got stuck w/ a tank like that years ago, and that is what I did, cap it and redrill.

SGT_York · 01/21/2014, 04:33 PM

Any reason you can't break the siphon to eliminate the need?

mcgyvr · 01/21/2014, 04:46 PM

Quote:

Originally Posted by r6justin

This is on my 150 with a bulkhead on bottom of tank flowing to sump.

Can you fix that? Then problem solved when you add a few anti-siphon holes to it..
Is this in an overflow box? pics?

r6justin · 01/21/2014, 04:52 PM

sorry I meant from the sump. Its my return. I figure with 2 check valves in a row would be better than 1. I have a 1.5" on there now that i'm not sure if I can remove easily.

my return setup
2 mag 7 pumps to 3/4" clear tubing to PVC adapter for 1.5" to Y to 1.5" flex pvc to 1.5" check valve to 1.5" bulkhead into tank.

mcgyvr · 01/21/2014, 05:56 PM

Quote:

Originally Posted by r6justin

sorry I meant from the sump. Its my return. I figure with 2 check valves in a row would be better than 1. I have a 1.5" on there now that i'm not sure if I can remove easily.
my return setup
2 mag 7 pumps to 3/4" clear tubing to PVC adapter for 1.5" to Y to 1.5" flex pvc to 1.5" check valve to 1.5" bulkhead into tank.

You could put a vertical pipe for the return with a siphon hole to bring it up to the surface and forget about check valves forever...

01/21/2014, 03:01 PM	#1
r6justin Registered Member Join Date: Jul 2010 Location: Dublin, OH Posts: 165	2 check valves together? as we all know check valves eventually leak. About every year I replace mine with a new one, and im thinking about running 2 right after each other. would this work, or not? 1. the flap is usually partially open and if valve 1 is shut but slowly leaks, valve 2 wouldn't have enough flow to close it. 2. or would valve 1 close, and leak, then fill valve2 and when water level hits the valve it will close and then would have enough pressure. 3. or would they both close at the same time and both be locked shut, since water was flowing to both and when the pump stops the water between the 2 valves would stop valve 2 and tank pressure would stop valve 1. since this is an air lock shouldn't the back pressure close both anyway because of the water draining down the hose? This is on my 150 with a bulkhead on bottom of tank flowing to sump.

01/21/2014, 04:24 PM	#2
davocean Registered Member Join Date: Nov 2005 Location: San Diego, CA Posts: 14,655	Sounds like double the headache to me, can you cap that bulk on the bottom and drill a new one where it should go? It would be more reliable and less headaches in the long run than what you are trying to do, which could just double the chance of a failure. I got stuck w/ a tank like that years ago, and that is what I did, cap it and redrill. __________________ There's a fine line between owning your tank and your tank owning you! Current Tank Info: SCA 120g RR Starfire, Tunze silence 1073.02 return, 40g sump w/ fuge, SWC Extreme 160 cone skimmer,Geismann reflexx 4xT5, 2x Panorama Pro LED strips, Vortech MP40QD

01/21/2014, 04:33 PM	#3
SGT_York Registered Member Join Date: Sep 2012 Location: Washington State Posts: 1,746	Any reason you can't break the siphon to eliminate the need?

01/21/2014, 04:52 PM	#5
r6justin Registered Member Join Date: Jul 2010 Location: Dublin, OH Posts: 165	sorry I meant from the sump. Its my return. I figure with 2 check valves in a row would be better than 1. I have a 1.5" on there now that i'm not sure if I can remove easily. my return setup 2 mag 7 pumps to 3/4" clear tubing to PVC adapter for 1.5" to Y to 1.5" flex pvc to 1.5" check valve to 1.5" bulkhead into tank.