Which One Way valves

Rainer Feyer · #1 05/31/2007, 09:20 AM

I am in the planning stages of an Auto Top off system using a peristaltic pump, a 1/4" hose from the basement tank to the sump - about 8 foot of height for the peristaltic to 'suck up'.

Two questions:

1) every plan I read about mentions one way valves, but which valves are good to use? I saw some @ McMaster's which need 25# of opening pressure (which seems like a lot to the uneducated mind). Any suggestions?

2) do any of you know ow much pressure the peristaltic pump create? (such as the simple pumps sold at MarideDepot)?

Thank you

Rainer Feyer · #2 06/04/2007, 06:31 AM

Bump

Any suggestions at all? I know many of you are using them - just a hint from where to get them,

thanks

mypurpletang · #3 06/04/2007, 05:43 PM

Bump for a good question

Kentanner11 · #4 06/04/2007, 07:52 PM

BUMP are those one way PVC valves at ACE/HD good for Reefing. GOOD QUESITON!!!

Rainer Feyer · #5 06/05/2007, 06:22 AM

Hmm,

I am hoping some of the 'valve experienced' reefers will chime in.

skamin · #6 06/05/2007, 08:07 AM

I think you are talking about a check valve. That only allows water to go in one direction, in the event water starts to back siphon the check valve will close. You can get these from your local petsmart for a few bucks. Try doing a search at marine depot for a check valve. hope that helps.

BeanAnimal · #7 06/05/2007, 08:59 AM

You will want to look at aquaticecosystems and get some small "duck bill" type check valves. Spring check may also work, but they may rust.

No, you don't have anywhere near 25psi of pressure to crack the check you mentioned.

I don't follow why you need them though. If the pump is upstairs, then the peristaltic pump (if it is a decent one) will lift the dosing fluid from the basement. The roller in the pump should pinch the hose and act like a check valve.

Randall_James · #8 06/05/2007, 09:18 AM

we just ran a couple tests on peristaltic pumps on an 8' lift... we only had 1 type of hose that worked, all the rest collasped on themeselves at the rollers after just a short period of time. One never worked at all.

We tried to move the pump to the level of the supply but it would not work (these are Baxter infusion pumps and have a pressure safety system, at about 2' of lift they shut off). A pump without the backpressure sensor might work but you will need to try it. (I can not bypass this safety feature on these pumps)

BeanAnimal · #9 06/05/2007, 09:45 AM

Randall, do you happen to have photos of the collapsed hose? What actual hose type ended up being rigid enough?

Was the problem exacerbated by the weight on the hose, or was it fully due to negative head?

I can see why the medical pumps would have a head pressure safety, you certainly don't want to pressurize a human being!

Rainer Feyer · #10 06/05/2007, 10:00 AM

Hi BeanAnimal and Randall_JAmes,

thank you both for your input. The reason for the one way check valve is in case the hose on the peristaltic pump breaks; just a safety issue. I am actually going to experiemetn, once the pump arrives, with the difference in pushing vs. pulling the kalkwasser.

Randall_James - I would imagine pushing will not cause the collapse you experienced? I'm not an engineer, so, what do I know - just a thought!

Thanks for the suggestion on the valves

Rainer

BeanAnimal · #11 06/05/2007, 10:41 AM

No pushing will not cause the collapse.

In the case of the line breaking, the fluid would simply drain back to the resevoir, there is not much fluid in a 1/8" 8' line.

Randall_James · #12 06/05/2007, 11:16 AM

the "did not collapse" hose was part of a Baxter IV set and was pretty rigid stuff. However I am sure that over time it will cave as well (the hose at the roller begins to collapse from the repeated compressions)

I think this pump setup is going to require a short, low head feed to work long term.

sorry I do not have a pump to check how much head pressure it can overcome

Randall_James · #13 06/05/2007, 11:17 AM

Quote:

Originally posted by Randall_James
Guess I can bring in a digital tomorrow and set this backup to photograph it.. not too much trouble

the "did not collapse" hose was part of a Baxter IV set and was pretty rigid stuff. However I am sure that over time it will cave as well (the hose at the roller begins to collapse from the repeated compressions)

I think this pump setup is going to require a short, low head feed to work long term.

sorry I do not have a pump to check how much head pressure it can overcome

BeanAnimal · #14 06/05/2007, 12:55 PM

Quote:

Originally posted by Randall_James
the "did not collapse" hose was part of a Baxter IV set and was pretty rigid stuff. However I am sure that over time it will cave as well (the hose at the roller begins to collapse from the repeated compressions)

I think this pump setup is going to require a short, low head feed to work long term.

sorry I do not have a pump to check how much head pressure it can overcome

That would make sense. The rollers weaken the tubing structure and soften it. The added suction head will keep it from springing back after time. The softer hose was not "springy" enough to recover in the first place.

I suppose the best otption is to use the pump in a pressure situation with as little suction head as possible to maximize tubing life.

I am glad you mentioned your experience. I was about to use a local pump to pull about 20' from another room. I will replan the setup now due to your observations.

BeanAnimal · #15 06/05/2007, 12:55 PM

Don't worry about the photos, I understand what is going on.

Kentanner11 · #16 06/05/2007, 08:30 PM

anyone know anything about the check valves at HD? Their PVC and have very specific mounting instructions.

BeanAnimal · #17 06/05/2007, 11:09 PM

What do you want to use them for?