Bidirectional tidal flow

MitchM · #1 12-07-2010, 04:00 PM

Quote:

Originally Posted by sphelps

.... You could do it with a single system and pump but you'd have to use special solenoid valves which will cost more than the additional pump and plumbing. .....

Do you have a specific solenoid and valve in mind?
I'm using Reeflo Dart Supergolds that are $500.

Thanks,
Mitch

sphelps · #2 12-07-2010, 04:11 PM

Quote:

Originally Posted by MitchM

Do you have a specific solenoid and valve in mind?
I'm using Reeflo Dart Supergolds that are $500.

Thanks,
Mitch

Yeah the solenoid valves would be more than that. I don't recall the brands but I've priced them out before for a customer and they we're fairly ridiculous because of the size and material needed to be aquarium safe.

Delphinus · #3 12-07-2010, 04:48 PM

A few years back I looked into the possibility of creating this kind of flow but using one pump. It was before OM was around. What I thought about using was a MOV (motor operated valve - electric in this case, although you can get pneumatic-activated as well) on a 3 way mixing valve. The trick is having the right ball in the valve so that as one side begins to close, the other begins to open so that the total flow through the valve remains constant at all times.

The reason I didn't pursue it was the cost of the MOV's was too prohibitive for me. I forget exactly where they were landing in price point specifically but I do recall thinking I would have done it if I could have found one for $200ish so I think it was well above that. The pneumatic ones were cheaper but then who wants to have a compressor going all the time and "psshhhhh!! psssssh!!! psssshhhhh!!" going on all the time in the tank room.

sphelps · #4 12-07-2010, 04:55 PM

Yeah and to use one pump you'll need at least 4 of those valves. A second pump with some additional holes and plumbing will be easier, cheaper and more reliable.

MitchM · #5 12-07-2010, 04:59 PM

LOL.

It sounds like it might boil down to another reeflo pump.
Now I need to find out how they stand up to constantly turning on and off.

I did find a 2" solenoid w/valve on the 'net, for a measly $2200.00.

Mitch

The Codfather · #6 12-07-2010, 05:17 PM

Don't know about prices, but here is a little info. from sequence:

http://www.mdminc.com/Doc/Sequence%2...ata_Sheets.pdf

golf nut · #7 12-07-2010, 05:24 PM

You can buy an $8 reed switch, sense the position of the drum then hook that to an Areotronics timer, select the time delay and you are done like dinner. net cost $39 .

MitchM · #8 12-07-2010, 05:32 PM

Codfather, thanks!

golf nut,

So I would use a 2-way OM unit?
What is a reed switch and Areotronics timer?

Thanks,
Mitch

sphelps · #9 12-07-2010, 05:41 PM

A reed switch works on magnetism, same type of switch you'd find on windows and doors for alarms. Problem is the OM has a thick plastic casing and you'd need pretty powerful switch to work properly and you would have to enclose one end within the drum which offers will space. Plus you'd need two switches for the two positions meaning you'll also need a smart relay to understand the two switches and control the system accordingly. It's certainly not as simple as described and the cost would be beyond $39.

schroeder · #10 12-28-2010, 03:05 AM

I have not checked into this but maybe there is another valve type that you could use.

I do service work on commercial dishwashing equipment. These machines sometimes use a valve that has a servo actuated diaphram to close 1 outlet (say the outlet to the wash arms) while opening the other (the drain).

They typically have cast ABS or PVC bodies but I cannot attest to the materials used inside the valve. I can however guarantee that they are under $250 and usually operate on 120V.

I'll try to get some contact info at work tomorrow and post if I find anything out.