Question on plumbing reeflo pump

[pizzaguy]

Plan and question. Have a reeflo goby pump. Coming out of sump with two 1" pipes then combining those down to 1 1/2" into the pump. Coming out gonna downsize to one inch into manifold with 3 valves and one inch returns. So basically is it OK that I only have a 1 inch pipe on the exit of the pump or is it gonna choke it down to much. I already have the manifold that's why I wanna downsize to 1 inch.

[AlanM]

It's definitely more kosher to choke down the output than the input.  Having said that, is there any way you could have larger coming out of the volute and then have a couple of 1" adapters off that to go to your manifold and two 1" returns?  So something like three 2" Tee fittings with a 1" socket for the Tee leg?

[pizzaguy]

When I get home I'll post a pick of the manifold. That might help

[GraffitiSpotCorals]

From what I remember I don't think 2 1" pipes is equal to the volume of space in a 1.5" pipe. So you may have cavitation issues, not sure if the small amount of pipe restriction will cause it or not. Generally I like to size the input up and avoid bends if I can. To many 90s or bends will cause cavitations as well.

Two one inch pipes one foot long have a volume of about .08 gallons.

One foot of 1.5" pipe has just over .09 gallons. If my math is correct

[pizzaguy]

[pizzaguy]

one inch in and out of the manifold.

[YHSublime]

I can give you one calculation, that that is your plumbing above= give or take $150. 

[pizzaguy]

[pizzaguy]

isaac would you believe ive had that manifold since i bought my cube i have now.

[pizzaguy]

i have found out that a easy way to avoid cavitation at the pump is to come out of sump with 2 -1" bulkheads then immediately tee into 1 1/2" pipe. put the pump at least 15" away from the sump which is 10 times the diameter of the 1 1/2" pipe.

[zygote2k]

scrap the manifold and start out right. 1.5 out of the pump and into the manifold, T's off the manifold can be whatever size you like- just use 1.5x1x1.5 

[GraffitiSpotCorals]

Well if your pump has 1" in and out your good.

[pizzaguy]

Pump is 1.5 in and out

[GraffitiSpotCorals]

Then you may have issues with the two 1" holes going into a 1.5" pump intake. Its not much of a size difference but generally not much is all it takes to have it run wrong.

[Origami]

scrap the manifold and start out right. 1.5 out of the pump and into the manifold, T's off the manifold can be whatever size you like- just use 1.5x1x1.5 

+1

 

The Goby's a flow-biased pump, much like the Barracuda. Flow drops off fairly rapidly with increased friction, which is what a bunch of 1" pipe is going to do. If you want to use that manifold, you could run 1-1/2" off the pump as far as you can take it and shorten all of your 1" runs and cap off the end of the manifold. Be aware though that you've essentially got a 1" backbone feeding three 1" takeoffs and that's where you'll see the greatest losses if you try opening up all three ball valves. To avoid this, another option is to run both ends off the manifold off of a 1-1/2" backbone - that is, loop both ends back to the pressure side to provide flow to manifold from both ends. This gives you twice the feed for the 3 take-offs. The better design is to use 1-1/2 or 2" piping as the main backbone and use a reducing tee 1-1/2" x 1" x 1-1/2" as takeoffs for your 1" valves. A cleaner install would be ground-up.

[GraffitiSpotCorals]

I would worry about your intake plumbing situation before making your manafold. Can you make the 1" holes bigger? 2 1.5" holes reducing into a 1.5" t before your pump would be ideal.

[pizzaguy]

SO CAN I JUST make the single hole out of sump a 1.5 inch hole and get a bigger bulkhead. That way it would be a straight 1.5 pipe into the pump. Is it safe to drill an existing hole bigger?

[GraffitiSpotCorals]

Should be fine to drill a bigger hole as far as I know. One 1 1.5" pipe is fine, just follow the rule of avoiding long runs and multiple bends before your intake to avoid cavitation.

[pizzaguy]

If I drill the whole bigger and use a 1.5 bulkhead I can put the pump as close as need be. Is there a bulkhead that has a 1.5 inch hole for the pipe to slip in without using a bunch of fittings?

[zygote2k]

yes- they make 1.5" slip or thread bulkheads but you still want a union gate valve between pump and sump to facilitate maintenance. having a foot of pipe run with fittings certainly isn't anything to worry about with cavitation. 

[pizzaguy]

That's the plan. Gonna build a new manifold. Will keep posted

[pizzaguy]

[pizzaguy]

I'm no artist so don't laugh. Does this sketch seem doable or are there problems? After pricing all these gate valves if there's a way to incorporate my manifold I would like to exercise it. The only 1 inch in this sketch would be the manifold itself with 1.5 running in and out of the manifold. And the return lines will have to choke down to the 1 inch bulkheads at some point.

[pizzaguy]

Forgot. Out of the manifold I could either close the valve and are it a pressure manifold or have it return back to the sump

[zygote2k]

It should go like this:

sump with 1.5" bulkhead, union ball/gate valve, pump intake, pump, pump out, union check valve, ball/gate valve, T. All of this should be 1.5" pipe to the T. The side of the T can be reduced down to incorporate the 1" manifold. After the T it should go to the returns with as much 1.5" as possible, then reduced down at the returns to 1"- both of which should have union ball/gate valves.