Mixing Box


Nan's NookArchives : Grow Chambers : Projects                 See: quality_mixing_boxes.pdf
Posted by: Propagator Aug 05 03, 07:14 PM GMT
There's a serious lack of info regarding mixing boxes and fungi terrariums, especially how to build them.

OK, I am almost to inebriated to type, but in chat an esteemed member of this board and myself concluded it would be a good idea to query everyone regarding this topic.

Does anyone have knowledge and/or experience with mixing boxes?

I will add my own two cents as sobriety overcomes me.

Posted by: highroller Aug 05 03, 07:17 PM GMT
Here's mine. Fungi Perfecti product. Inside view. The large area to the right houses the HEPA filter. The bottom hole to the right house the adjustable damper. The bottom hole to the left is where the old fogger humidifier hose hooked up. Now blocked off. Using ultrasonics now.

To far right is where it hooks up to squirrel cage in next pic. To the left is the output of filtered mixed air.


Posted by: highroller Aug 05 03, 07:18 PM GMT

Outside view. Ghetto duct taped hole to left is where the fogger hose used to go through to hook up with mixing box.


Posted by: Propagator Aug 05 03, 07:22 PM GMT
i've checked fungi perfecti and havent seem anything near that.

in fact, I'm not even sure what I'm looking at.

Posted by: Propagator Aug 05 03, 07:26 PM GMT
Ok, after re-reading the first post I understand what is happening, but not so much with the outside pic?

how's the ultrasonic feed the blower?

Posted by: highroller Aug 05 03, 07:35 PM GMT
They don't. The ultrasonics sit on a shelf inside the fruiting chamber and are adjusted to keep the proper humidity.
There's one of three to the right.


Posted by: dcyans Aug 05 03, 07:41 PM GMT
Damn another free desktop bannana.gif bannana.gif bannana.gif bow.gif bow.gif bow.gif wub.gif wub.gif tongue.gif wink.gif

Posted by: Maineiac Aug 05 03, 08:06 PM GMT
Nice goin Prop cool.gif

Highroller your grows are UNREAL MAN!!! ARE YOU POSESSED BY FUNGAL ENTITIES? SCHNEIKIES!

Before I list a tirade of questions can you (or anyone) explain what a (yours or in general) mixing box does and how it does it? I got a lot from your dialogue with mycofile in your thread a few weeks back but it was piecemeal...

peace.gif

Posted by: highroller Aug 05 03, 08:16 PM GMT
Basically it positively pressurizes the fruiting chamber with filtered outside air mixed with already conditioned inside air to maintain a healthy environment for the fugus to thrive. It gives one control via an adjustablr damper over temperature, humdity, ventilation and circulation.

Posted by: Maineiac Aug 05 03, 08:29 PM GMT
Sweet HR thanks a bunch for the info, I've been wondering about this ever since you mentioned it.

Posted by: Fungusmaximus Aug 06 03, 04:05 AM GMT
wink.gif
MIXING BOXES AND TERM INAL UNITS 15869 - 1
(Rev.11/1/00)
SECTION 15869
MIXING BOXES AND TERMINAL UNITS
PART 1 GENERAL
1.1 SUMMARY (Not Applicable)
1.2 REFERENCES (Not Applicable)
1.3 SUBMITTALS
Refer to Section 15003, SD-15, 17, 31, 33, 34, 40, 41, 42, 56, 70, 76, 80, 90 and 92.
1.4 GENERAL REQUIREMENTS
Section 15003, "General Mechanical Provisions," applies to work specified in this
section.
PART 2 PRODUCTS



2.1 HIGH-PRESSURE DUAL-DUCT MIXING BOXES
Units shall be mechanical constant-volume control type with a mechanical controller that
is operated by the entering mixed-airstream and maintains a constant airflow through the
unit.


2.1.1 Construction
Unit shall be factory assembled, complete with casing, air mixing valve assembly, single
air mixing valve operator, and mechanical constant-volume control, ready for field
mounting and connection to control.
Casing exterior shall be not less than 0.040-inch-thick aluminum, or not less than 20-gage
mill-galvanized steel with not less than 1.25 ounces of zinc per square foot of two-sided
surface, conforming to ASTM A527.
Casing interior shall be acoustically baffled and lined with Steri-Loc liner or equivalent
and thick enough to attain required sound power level performance and preclude
condensation on any exterior surface, but in no case less than 1 inch. Air side of liner
shall be manufactured to resist delamination or surface erosion at air velocities to 4,000
feet per minute. Liner edges exposed to airstream shall be protected by metal turnovers.
Liner and baffle material shall conform to NFPA 90A.
All Units (research laboratory and vivarium only) shall use Steri-Loc or equivalent
coverings confirming to NFPA 90 standard over perforated metal cover liner with an
erosion proof surface meeting ASTM C 1071- 91 test. The liner must have passed and
shown NO observed growth for the test for mold growth and humidity using UL 181 test,
fungi resistance ASTMC 1071 and ASTMG-21 tests and bacteria growth using ASTMG
MIXING BOXES AND TERM INAL UNITS 15869 - 2
(Rev.11/1/00)


22 test.
Inlet valves and connecting linkage shall be constructed for modulation by a single
operator. The hot inlet valve shall be normally open, and the cold inlet valve shall be
normally closed. Hot and cold inlet ports shall be field reversible.
Mechanical constant-volume control shall be externally adjustable and shall have a
cubic-feet-per-minute graduated capacity scale, which also indicates minimum/maximum
range of the unit.
Components subject to friction shall have oil-impregnated bronze bearings,
graphite-impregnated or lubricant-impregnated nylon bearings; and
lubricant-impregnated elastomers, corrosion-resistant steel, and similar materials.
Casing shall be fitted with rigid, airtight access panels, easily removable and of ample
size to give free access to interior parts. Closure shall be achieved by spring-retained,
quarter-turn, slotted-cam captive devices, or similar operating fasteners.
Caulking compounds shall be chloroprene, polyurethane polysulfides, or silicone
elastomers. Gaskets shall be chloroprene, polyurethane, or vinyl.

2.1.2 Casing Leakage
Casing joints shall be sealed to prevent leakage of no more than 2 percent of rated
capacity with all connections sealed and with an internal static pressure of 1 inch wg.


2.1.3 Inlet Valve Leakage
Leakage in fully closed valve position shall not exceed 2 percent of unit rated capacity
against inlet pressure of 8 inches wg.


2.1.4 Mixed-Air Temperature Requirements
A thermometer traverse of all unit outlets shall show variation of not more than 5 percent
of the difference, at the time, between the temperatures of equal quantities of cold and
warm airstreams entering the unit.


2.1.5 Volume Control Requirements
Mechanical constant-volume control shall maintain design volume within plus or minus 5
percent, regardless of the modulation position of inlet valves or the fluctuation of inlet or
outlet pressure, within limits of indicated minimum pressure.

2.1.6 Sound Level Requirements
Unit shall meet the airborne and radiated sound-power level (PWL) requirements
scheduled, to attain the specified NC levels. An 18-dB space attenuation shall be
assumed in all octave bands with consideration given to downstream duct construction
and configuration in determining airborne NC levels.
The following ceiling sound-transmission loss (TL) characteristics, based on 1-inch


MIXING BOXES AND TERM INAL UNITS 15869 - 3
(Rev.11/1/00)
acoustic lay-in panels and T-bar suspension, shall be assumed in computing resultant
space radiated NC levels:
OCTAVE BAND 2ND 3RD 4TH 5TH 6TH 7TH
PWL-TL -2 -4 -9 -10 -13 -15
NC40 shall be the limiting factor.

2.1.7 Control Requirements
Operating-control power source shall be dry, compressed air of instrument quality at 15
pounds per square inch, gage, unless otherwise approved.
Air mixing valve operator shall be provided by the automatic temperature control
manufacturer and installed by the unit manufacturer, unless field installation for specific
construction is approved. Operator shall be controlled by a direct-acting thermostat.
Pneumatic control tubing shall be copper and shall be brought to the exterior of the casing
for connection to automatic temperature control system.


2.2 LOW-PRESSURE DUAL-DUCT MIXING BOXES
Units shall be manual-damper volume control type. A calibration chart shall be provided
with each unit. Each unit shall be labeled with capacity minimum/maximum range to
facilitate field adjustment.
Volume control damper shall be externally adjustable over an inlet pressure range of 0.05
to 1 inch wg.
Components subject to friction shall have oil-impregnated bronze bearings,
graphite-impregnated nylon bearings, and lubricant-impregnated elastomers,
corrosion-resistant steel, and similar materials.
Casing shall be fitted with rigid, airtight access panels, easily removable, and of ample
size to give free access to interior parts.
Closure shall be achieved by spring-retained, quarter-turn, slotted-cam captive devices or
similar operating fasteners.
Caulking compounds shall be chloroprene, polyurethane polysulfides, or silicone
elastomers. Gaskets shall be chloroprene, polyurethane, or vinyl.


2.2.1 Casing Leakage
Casing joints shall be sealed to prevent leakage of more than 2 percent of rated capacity,
with all connections sealed and with an internal static pressure of 1 inch wg.
2.2.2 Inlet Valve Leakage
Leakage in fully closed valve position shall not exceed 2 percent of unit rated capacity
against inlet pressure of 1 inch wg.
MIXING BOXES AND TERM INAL UNITS 15869 - 4
(Rev.11/1/00)


2.2.3 Mixed-Air Temperature Requirements
A thermometer traverse of all unit outlets shall show variation of not more than 5 percent
of the difference, at the time, between the temperatures of equal quantities of cold and
warm airstreams entering the unit.


2.2.4 Sound Level Requirements
When determining equipment sound power level performance when no space-attenuation
criteria are given, 18-dB space attenuation shall be assumed in all octave bands. The
manufacturer shall take into account sound correction factors for equipment such as
multiple-terminal air device outlets and attenuation due to any duct lining using sound
absorption values specified in Section 15258, "Duct Insulation," entitled "Acoustic Duct
Lining."

2.2.5 Control Requirements
Operating-control power source shall be dry, compressed air of instrument quality at 15
psig, unless otherwise approved.
Air mixing valve operator shall be provided by the automatic temperature control
manufacturer and installed by the unit manufacturer, unless field installation for specific
construction is approved. Operator shall be controlled by a direct-acting thermostat.
Pneumatic control tubing shall be copper and shall be brought to the exterior of the casing
for connection to automatic temperature control system.
2.3 SINGLE DUCT, CONSTANT VOLUME, TERMINAL REHEAT UNITS
Units shall include a casing, volume regulators, sound attenuating thermal insulation
equivalent to Steri-loc, and heating coils.


2.3.1 Casing
Unit casings shall be constructed of 0.040-inch aluminum or 20-gage mill-galvanized
steel and shall contain removable panels for access to interior parts. Units shall be
insulated internally with minimum -inch-liner equivalent to Steri-loc acoustic
insulation, conforming to NFPA 90A.
All Units (research laboratory and vivarium only) shall use Steri-Loc or equivalent
coverings confirming to NFPA 90 standard over perforated metal cover liner with an
erosion proof surface meeting ASTM C 1071- 91 test. The liner must have passed and
shown NO observed growth for the test for mold growth and humidity using UL 181 test,
fungi resistance ASTMC 1071 and ASTMG-21 tests and bacteria growth using ASTMG


22 test.
Unit shall contain sound-attenuation provisions including baffles to minimize unit-created
noise.
2.3.2 Regulators
MIXING BOXES AND TERM INAL UNITS 15869 - 5
(Rev.11/1/00)
Units shall contain a mechanical constant-air volume control designed to operate by inlet
air pressure without outside power. Regulators shall be constructed of nonferrous parts
and shall be guaranteed to maintain delivered air volume at plus or minus 5 percent of
unit rating.


2.3.3 Coils
Water coils shall be constructed of not less than 3/8-inch outside diameter seamless
copper tubing with copper- or aluminum-plate fins mechanically bonded or soldered to
the tubes, and with not less than 5/8-inch outside diameter female solder connectors and
manual air vent on return. Coils shall be tested under water at 150 percent of the working
pressure or 300 psig for 200 pounds per square inch working pressure. Provisions shall
be made for coil removal in field.
Distance between coil and upstream inlet valve shall ensure uniform air velocities over
face of coil.


2.3.4 Controls
Reheat output shall be controlled by a room thermostat designed to modulate the water
flow in the coil by positioning a three-way valve.
2.4 VARIABLE CONSTANT-VOLUME BOXES
The casing shall be fabricated from galvanized steel and shall have internal thermal and
acoustic insulation material equivalent to Steri-Loc and shall conform to NFPA 90A.
All Units (research laboratory and vivarium only) shall use Steri-Loc or equivalent
coverings confirming to NFPA 90 standard over perforated metal cover liner with an
erosion proof surface meeting ASTM C 1071- 91 test. The liner must have passed and
shown NO observed growth for the test for mold growth and humidity using UL 181 test,
fungi resistance ASTMC 1071 and ASTMG-21 tests and bacteria growth using ASTMG


22 test.
Sound baffles sh all b e p rovided w ithin the box to provide sound lev els
within the limits scheduled. Sou nd levels shall be tested in accordance
with AN SI S1.23. An 8-dB room attenuation shall be used in determining
the NC level. A llowances shall be made for m ultiple outlets (power
division) and duct a tten uatio n.
Casing internal leakage shall be limited to 2 percent of nominal box
capacity w hen the in ternal p ressure is 1 inch w g.
Casing shall be fitted w ith rigid, airtight access panels, easily removable,
and of ample s ize to give free acces s to all interior p arts.
Each box shall be labeled with building location and factory-set air volume
or fie ld-set c alib ration cu rve.


2.4.1 Low Velocity Boxes
Inlet v alv e shall b e s elf-seating, and leakage in fu ll clo sed position sh all
MIXING BOXES AND TERM INAL UNITS 15869 - 6
(Rev.11/1/00)
not exceed 2 percent of unit rated capacity against inlet pressure of 1 inch
wg.

2.4.2 Medium and H igh V elo city Boxes
Box shall be supplied with variable constant-volume regulator consisting
of aluminum and co ated-steel frame w ith alum inum vanes,
co rro sion-re sistan t ste el adjusting sp ring, and neoprene pulsa tion snubber.
Volume reset shall be by pneumatic operator mounted directly on the
variab le constant-volume regulato r.
The v ariab le constant-volume regulato r sh all b e factory se t for an air
capacity w ithin plus 5 percent of the indicated m axim um and m inim um air
quantities, regardless of variations in inlet static pressure from m inimum
to 6 inch es w g.
Minimum air capacity shall be a percentage of the maximum air capacity
indica ted and sh all b e e as ily ch anged in the field.
A calibration chart indicating 100 percent air capacity versus adjusting
sc rew sh all b e furn ish ed w ith each box.


2.4.3 Control Requirem ents
Operating-control power source shall be dry, compressed air at 15 psig
unles s o therwise approved.
Valve operator shall be provided by the automatic temperature control
manufactu rer and installed by the unit m anufactu rer, unless fie ld
installation for specific construction is approved. Operator shall be
contro lled by a th ermosta t.
Pneumatic control tubing shall be copper and shall be brought to the
exterior of the casing for connection to automatic temperature control
sy stem.
PART 3 EXECUTION

3.1 INSTALLATION
Equipment shall be installed as show n on the drawings and in accordance
with the m anufactu rer's recommendatio ns.
MIXING BOXES AND TERM INAL UNITS 15869 - 7
(Rev.11/1/00)
-- End of S ection --

Posted by: Fungusmaximus Aug 06 03, 04:14 AM GMT
Here is an excellent how to on mixing boxes with pics and parts lists. Several different models as well wink.gif wub.gif

http://www.nansnook.com/archives/tek/quality_mixing_boxes.pdf wub.gif

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