Pump size

[fatheads]

Trying to figure correct pump size

How many GPM for a 7 bbl fermenter?

We have a 5ton with a 2hp pump
6 7bbl and 1 14 bbl fermenters..about 30 ft head...can't seem to get the pressure lower than 12..when pump cycles pressure raises to 20psi thn drops back to 12..13 psi
fridge guy says pump is oversized

[lhall]

more info please...

[fatheads]

ok what in particular

[HinduKush]

Trying to figure correct pump size

How many GPM for a 7 bbl fermenter?

We have a 5ton with a 2hp pump
6 7bbl and 1 14 bbl fermenters..about 30 ft head...can't seem to get the pressure lower than 12..when pump cycles pressure raises to 20psi thn drops back to 12..13 psi
fridge guy says pump is oversized

Do you mean the pressure increases when the solenoid opens or is the circulation pump wired to the temp. control? If you have a closed loop the pump should run 24/7. Wire a VFD to the pump and dial it down to suitable pressure. Should be cheaper than replacing the pump. I have run 6 - 15, 2 - 7, and one 30 bbl unitank with a half horse pump, but all tanks were on grade.

[Fred Scheer]

Pump

Dry to call some pump supplier; but have the following info ready to give them:

• The products you pump
• Product viscosity
• Product temperature
• Desired flow rate
• In-line devises you may have, such as heat exchanger, or fittings that cause resistance to the flow.
There are some terms used with pumps, let me explain them in short.
TOTAL DYNAMIC HEAD (TDH), is the vertical distance between your pump discharge and the highest point in the discharge pipes plus friction head, minus the positive head.
POSITIVE SUCTION HEAD is the vertical distance between the pump inlet and the level of the product supplied to the pump
Length of your hoses to and from pump, and the diameter.
Also, watch the seal in your pump, as it will be affected by temperature.
If your pump is exposed to all the elements in the Brewery; Beer, CIP caustic, 2.5 % and 160*F, I recommend you get so called EPDM or PTFE seals.
As Linus said in his post, please provide more info and we can get you an example calculation.
Cheers
Fred

[fatheads]

We got about 60 ft of 1 1/2 pvc that reduces to 3/4 flex hose after the solenoids which adds about another 30 ft in flex hose.
head is 30 ft
6/7bbl and 1 /14 bbl fermenters
fridge guy says 2 hp is way to big..we need more like a 1/3 hp to maintain 8/10psi
what other info should I supply

Thanks

[jimvgjr]

2 HP does seem oversized, does this pump also circulate glycol through your chiller evaporator, or is there a dedicated pump for this.

I suspect the reason the pump is so large, they are using a single pump for dual purpose (1. circulate to the brewery and 2. circulate through your chiller evaporator). Reducing the flow throw the chiller evaporator could cause a completely new set of problems.

If it is a dedicated pump for the brewery loop (60' 1.5" pipe with 7 EA jacketed vessels)- I'd probably suggest a 3/4 HP, or maybe 1/2 HP, a 1/3 HP seems very small. As a quick rule of them, I'd estimate 5-10 GPM per vessel, 70 GPM would be maximum flow and use 45 GPM for an average flow (maximum flow X 60%).

Another option you can use if the 2 HP is shared and circulates through the evaporator; adding a pressure bypass valve at the end of the SUPPLY header that automatically bypasses into the RETURN Header if pressure exceeds a setpoint (15 PSIG). You will still be running a bigger pump than is required, this will however protect tank jackets from overpressure. This link to an older probrewer post has an option from McMaster Carr http://www.probrewer.com/vbulletin/s...ressure+bypass

Good Luck,

Jim
Pro Refrigeration Inc.

[Fred Scheer]

pump

HI

I would recommend:

HP 1.5
VOLTS 208 230/460
AMPS 4.9 - 4.6/ 2.3
RPM 3450
HZ 60
PH 3

Cheers

[fatheads]

majority seems to be the pump is oversized and to install a vfd
yes..no?
cheers!