HyQuest Solutions HS40C User manual

HS40C
User Manual
07-2022 – 01-00-000

© 2022 HyQuest Solutions 2
Table of Contents
I Disclaimer 3
II Safety Instructions 4
Part I Introduction 5
1.1 Product Overview ................................................................................................................................................. 6
Part II Installation 8
2.1 Power Connection ................................................................................................................................................. 8
2.2 Extending the Battery Cables .......................................................................................................................... 8
2.3 Adjusting the Bubble Rate .............................................................................................................................. 10
2.4 WL3100 Connection ......................................................................................................................................... 11
Part III Operation 12
3.1 Control Valve ........................................................................................................................................................ 12
3.2 Startup Sequence ................................................................................................................................................ 12
3.3 Tank Pressurisation & Mist Separator Flushing ..................................................................................... 12
3.4 Battery Size ........................................................................................................................................................... 13
3.5 Battery Voltage .................................................................................................................................................... 13
Part IV Maintenance 15
4.1 Automatic Moisture Extraction ..................................................................................................................... 15
4.2 Filter Maintenance ............................................................................................................................................. 16
Part V Troubleshooting 18
Part VI Repair 19
Part VII Technical Data 20
Part VIII Obligations of the Operator and Disposal 22
8.1 Obligations of the Operator ........................................................................................................................... 22
8.2 Dismantling / Disposal ..................................................................................................................................... 22
Part IX Appendices 24
9.1 Appendix A Installing Polyethelene Tubing and Orifice Fittings ................................................... 24
9.2 Appendix B Using Pressure to Measure Water Level .......................................................................... 25
9.3 Appendix C HS40 Compact-DO (Dual Orifice) ........................................................................................ 31
9.4 Appendix D Gas Chamber Orifice Assembly GC01P/SS ...................................................................... 31
9.5 Appendix E Typical Installations ................................................................................................................. 34

Copyright Notice: No parts of this work may be
reproduced in any form or by any means without
the written permission of the publisher. HyQuest
Solutions waives copyright for users to print out
parts of the documentation in hard copy for their
own use only.
Trademark Notice: HyQuest Solutions (HS) and
KISTERS products and services referred to in this
document are trademarks or registered trademarks
of HyQuest Solutions or KISTERS AG. Other product
names used may or may not be the trademarks of
their respective owners.
© 2020 HyQuest Solutions, a KISTERS Group
Company. Any rights not expressly granted herein
are reserved.
The information provided in this manual was
deemed accurate as of the publication date.
However, updates to this information may have
occurred.
This manual does not include all of the details of
design, production, or variation of the equipment
nor does it cover every possible situation which may
arise during installation, operation or maintenance.
HyQuest Solutions shall not be liable for any
incidental, indirect, special or consequential
damages whatsoever arising out of or related to this
documentation and the information contained in it,
even if HyQuest Solutions has been advised of the
possibility of such damages.
Any errors found in any HyQuest Solutions product
should be reported to HyQuest Solutions where
every effort will be made to quickly resolve the
problem.
This document is public.
3© 2022 HyQuest Solutions
I Disclaimer

§ Read the user manual including all operating instructions prior to installing, connecting and powering up the
HyQuest Solutions HS40C. The manual provides information on how to operate the product. The manual is intended
to be used by qualified personnel, i.e. personnel that have been adequately trained, are sufficiently familiar with
installation, mounting, wiring, powering up and operation of the product.
§ Keep the user manual on hand for later reference!
§ If you encounter problems understanding the information in the manual (or part thereof), please consult the
manufacturer or its appointed reseller for further support.
§ HyQuest Solutions HS40C is intended to be used in hydrometeorological or environmental monitoring applications.
§ Before starting to work, you have to check the functioning and integrity of the system.
§ Check for visible defects on the HS40C, this may or may not include any or all of the following mounting
facilities, connectors and connections, mechanical parts, internal or external communication devices, power
supplies or power supply lines, etc.
§ If defects are found that jeopardize the operational safety, work must be stopped. This is true for defects found
before starting to work as well as for defects found while working.
§ Do not use the HyQuest Solutions HS40C in areas where there is a danger of explosion.
§ The present user manual specifies environmental/climatic operating conditions as well as mechanical and electrical
conditions. Installation, wiring, powering up and operating the HyQuest Solutions HS40C must strictly comply with
these specifications.
§ Perform maintenance only when tools or machinery are not in operation.
§ If guards are removed to perform maintenance, replace them immediately after servicing.
§ Never make any electrical or mechanical diagnostics, inspections or repairs under any circumstances. Return the
product to the manufacturer’s named repair centre. You can find information on how to return items for repair in
the relevant section of the HyQuest Solutions website.
§ Disposal instructions: After taking the HyQuest Solutions HS40C out of service, it must be disposed of in
compliance with local waste and environmental regulations. The HyQuest Solutions HS40C is never to be disposed
in household waste!
§ Inputs and outputs of the device are protected against electric discharges and surges (so-called ESD). Do not
touch any part of the electronic components! If you need to touch any part, please discharge yourself, i.e. by
touching grounded metal parts.
II Safety Instructions
© 2022 HyQuest Solutions 4

© 2022 HyQuest Solutions 5
Introduction
1Introduction
Thank you for choosing our product. We hope you will enjoy using the device.
HyQuest Solutions manufactures, sells, installs and operates quality instrumentation, data loggers and communication
technology. Products are designed with passion for environmental monitoring and with a deep understanding of the
quality, accuracy and robustness needed to fulfil the requirements of measurement practitioners in the field.
The present User Manual will help you understand, install and deploy the device. If, however, you feel that a particular
information is missing, incomplete or confusing, please do not hesitate to contact us for further support!
The HS40 Compact Gas Purge Compressor + Bubbler System has been designed to replace a conventional nitrogen gas
bottle supply to a bubble unit/gas purge system, used for measuring water level in dams, rivers, canals and tanks with
up to 40 mH2O (130 ft) head with a maximum river-line length of 200 m (650 ft). (Note: 50 mH2O (160 ft) available on
request)
The basic system consists of an air compressor, a 0.75 litre receiving tank, an advanced membrane dryer, micro mist
separator (with optional V-series auto purge valve for the micro mist separator), a highly reliable mechanical
differential bubbler system, bubble rate check function, high quality Australian made compressor pump packaged into a
small but robust metal enclosure. The system incorporates a mechanical pressure switch to maintain a 400kPa (58 psi)
- 750 kPa (110 psi) tank pressure to ensure powerful river line purging during site visits.
The HS40 Compact, with the optional inbuilt WL3100 pressure transducer, allows the measurement of water level to an
accuracy of ±0.02 % F.S. (The WL3100A is an advanced model that allows the fine tuning of the “user factor”
relationship between pressure and water level, and is temperature compensated from -40 °C to 80 °C) The inbuilt
WL3100 / WL3100A have an SDI-12 interface and a 4 - 20 mA interface that can be used at the same time to provide
data to 2 separate systems if required.
Advantages over other systems:
§ Compact single unit.
§ Low maintenance (no gas bottle or desiccant to be replaced) two stage air drying system incorporating micro-mist
separator and self-purging membrane dryer to ensure clean dry air is available in all conditions. A yearly check of
the internal filter element is recommended, however up to three years before replacement is possible depending on
site conditions. (Low cost replacement elements can be purchased from HyQuest Solutions when required.)
§ Can interface WL3100 to SDI-12 and 4 - 20 mA outputs simultaneously.
§ Easy to install.
There are various models available:
HS40AFC
Includes compressor tank air dryer bubbler.
HS40AFC/2100
Compressor/bubbler above with inbuilt 2100 pressure transducer.
HS40AFC/3100
Compressor/bubbler above with inbuilt WL3100 pressure transducer.

© 2022 HyQuest Solutions 6
Introduction
HS40AFC/3100A
Compressor/bubbler above with inbuilt WL3100A pressure transducer.
(Full operation down to -40 °C)
.…/DI
Above model + dual instrument port feature.
.…/DO
Above model + dual orifice feature.
.…/V
Above model + auto purge of stainless micro mist separator.
1.1 Product Overview
The Model HS40 Compact is designed to replace conventional Dry Nitrogen bubbler systems for water level
measurement. The standard unit operates up to 40 m (130 ft) head of water (and up to 50 m (160 ft) upon request).
The system is low maintenance and has a low average power consumption.

© 2022 HyQuest Solutions 7
Introduction

© 2022 HyQuest Solutions 8
Installation
2Installation
The HS40 Compact MUST be mounted in a vertical position (not laying flat as shown). The micro mist separator and
auto purge moisture feature will not function properly if the unit is mounted in a horizontal position.
Before connecting 12V power to the HS40 Compact, fit the 3/8 inch river-line where shown (optional ¼ inch fitting).
Connect the 12V DC battery directly to the power cable shown, and add a mains or solar charger if required.
If the tank pressure is less than 400kPa (58psi) [±20%], the compressor will start and pump the tank pressure up to
750kPa (110psi) [±20%]. This initial pump up cycle will take approximately 10 secs.
This chapter contains the following subsections:
§ Power Connection
§ Extending the Battery Cables
§ Adjusting the Bubble Rate
§ WL3100 Connection
2.1 Power Connection
The 6 mm2power cable provided must be connected directly to the power source – either a 12 V / 38 Ah (min) battery
OR a 12 V to 13.8 V power supply rated at 40 A. When the compressor operates it will draw about 20A black Thomas
pump (or 30Amps for the previous blue ARB pump).
2.2 Extending the Battery Cables
The HS40 Compact is supplied with a 2 m power cable, with each core being 6 mm2. If the user needs to extend this
cable, extreme caution should be exercised, because whenever high currents are drawn through cables, there will be
voltage drops!
With the supplied cable (2 m of 6 mm2) there is a 0.18 V drop on each conductor when the compressor draws 30 A
(worst case for the previous blue ARB pump). Since there is a positive and negative wire, the voltage seen by the HS40
8
8
10
11

© 2022 HyQuest Solutions 9
Installation
Compact is 2 × 0.18 V = 0.36 V less than the voltage seen at the battery terminals – and at 30 A (again worst case) the
battery voltage will also droop. (This is before the cables are extended.)
Use the following table to get an idea of the total cable voltage drop – keeping in mind the HS40 Compact will
disconnect the compressor when the voltage “it sees” drops below 10 V.
Extended Cable
Length
Cable Size
(mm2/ AWG)
Vdrop1 on
extended cable
Vdrop2 on
supplied cable
Total
Vdrop
Actual Vbatt
when HS40
Compact
disconnects
compressor
2 m (6 ft)
6 / 9.5
0.36 V
0.36 V
0.72 V
10.72 V
4 m (12 ft)
6 / 9.5
0.72 V
0.36 V
1.08 V
11.08 V *
6 m (18 ft)
6 / 9.5
1.08 V
0.36 V
1.44 V
11.44 V *
4 m (12 ft)
10 / 7
0.42 V
0.36 V
0.78 V
10.78 V
6 m (18 ft)
10 / 7
0.6 V
0.36 V
0.96 V
10.96 V
10 m (30 ft)
10 / 7
1.02 V
0.36 V
1.38 V
11.38 V *
15 m (45 ft)
10 / 7
1.50 V
0.36 V
1.86 V
11.86 V *
15 m (45 ft)
16 / 5
0.96 V
0.36 V
1.32 V
11.32 V *
20 m (60 ft)
16 / 5
1.26 V
0.36 V
1.62 V
11.62 V *
* => Not Recommended
Note: A minimum battery capacity of 38 Ah is recommended, to lessen the battery voltage drop under heavy load.

© 2022 HyQuest Solutions 10
Installation
2.3 Adjusting the Bubble Rate
· Set the River Line control valve to the “Close” position.
· Attach the HS23QC (supplied as an option) to the HS40 Compact Test Port and immerse the HS23QC in a beaker of
water.
· Allow up to 10 minutes for the bubble rate and differential regulator to stabilize.
· Undo the bubble rate locking screw and adjust the bubble rate (to say 21 bubbles/min) The bubble rate at the Test
Port will indicate the expected River Line rate at the orifice. Nip up the lock screw and check the bubble rate again –
it may change slightly when the lock screw is done up. CAUTION: ADJUSTMENT OF THE BUBBLE RATE HIGHER THAN
THE MAXIMUM 45 BPM WILL VOID THE MANUFACTURER WARRANTY ON THIS PRODUCT.
· Disconnect the HS23QC from the HS40 Compact Test Port.
· Rotate the River Line control valve from the “Close” position to the “Open” position to direct the bubbles from the
“Test Port” back to the “River Line”.
· (Please note leaving the purge valve in the closed position for more than 30 seconds after removing the HS23QC
could expose the transducer element to excessive pressure, damaging the element)
Actual Bubble Rate setting at Test Orifice or River Line (bubbles/min)
Suitability
10 Bubbles Per Minute
(Recommended forGC01P/SS)
Suitable for Slow rising streams
16 Bubbles Per Minute
21 Bubbles Per Minute
26 Bubbles Per Minute
Factory Set Rate (Recommended for BU07)
For medium rising streams
Maximum do not exceed 45 Bubbles Per Minute
Suitable for Fast rising streams
EXCEEDING THE MAXIMUM BUBBLE RATE WILL CAUSE EXCESIVE WEAR TO
COMPRESSOR PUMP

© 2022 HyQuest Solutions 11
Installation
2.4 WL3100 Connection
12
+12V DC Power
Da
SDI-12 Data
0V
0V DC Power
+S
+ve 4-20mA Signal
-S
- ve 4-20mA Signal
The WL3100 measures the river-line pressure and provides water level information. Wiring connections to the WL3100
are via a 6 way plug-in terminal block underneath the HS40 Compact enclosure. You must have +12V and 0V power for
the WL3100 to operate. You may connect the SDI-12 and the 4-20mA interfaces at the same time. (These terminals
are “screwless” and keep a constant tension on the wire, thus producing a more reliable connection – simply use a
screwdriver to push on the orange lever to release the terminal spring tension, to insert or remove the wire.)
You may connect the WL3100 to the same battery used to power the compressor, but it is advised to cable it directly
back to the battery – so that any voltage drops that occur down the compressor power cables, are not seen by the
WL3100.
(Consult the WL3100 Manual for a detailed description of the WL3100 connection, operation and specific SDI-12
commands – available on the HyQuest Solutions website)
If connecting to the 4-20mA interface, make sure that the data logger (or RTU) powers up the 4-20mA loop long
enough for the WL3100 to recognise it, take a measurement and put the result back on to the 4-20mA loop. (1 sec
when “Sampling Mode” is set to “Contin+Avg X” and 15 secs when “Sampling Mode” is set to “Single”)

© 2022 HyQuest Solutions 12
Operation
3Operation
This chapter contains the following subsections:
§ Control Valve
§ Startup Sequence
§ Tank Pressurisation & Mist Separator Flushing
§ Battery Size
§ Battery Voltage
3.1 Control Valve
The River Line Control Valve has 3 positions:
“Open”
In the Open position, the bubbler (regulator) is open to the River Line port and the
transducer.
“Close”
In the Close position, the bubbler (regulator) is closed to the River Line. (If there is nothing
plugged into the Test Port Quick Connect, the transducer pressure will continue to increase
very slowly as the regulator reacts to a closed system – DO NOT leave it in this position for
extended periods as the internal pressure build up may exceed the burst pressure of the
transducer element !!!!) Note: The cabinet door has an interlock that prevents the door from
being closed while the valve is in the “Close” position.
“Purge”
In the Purge position, the receiver tank is directly connected to the River Line port to allow a
Purge of the River Line. After a River Line Purge is performed, rotate the control valve back
to the Close position and wait until the River Line pressure drops to a normal level (say 10
seconds) before rotating the control valve back to the Open position. (Otherwise the Purge
pressure may be introduced to the transducer and cause damage!!!)
IMPORTANT: When purging, STOP when the tank pressure falls below 400kPa, otherwise the river-line pressure may fall
below the water head pressure resulting in water entering the River Line!
3.2 Startup Sequence
After power is first applied, the compressor will turn on if the tank pressure is below 400 kPa.
3.3 Tank Pressurisation & Mist Separator Flushing
When the tank pressure falls below 400kPa (58psi) [±20%], the Condor pressure switch will close, causing the controller
to turn on the compressor and then pump the pressure back up to 750kPa (110psi) [±20%].
12
12
12
13
13

© 2022 HyQuest Solutions 13
Operation
Note: Always leave the system with the Condor (pressure) switch manual over-ride in the “1” (on) position!!
3.4 Battery Size
The HS40 Compact electronics consumes a quiescent of about 12mA and draws about 20A for 30 secs (black Thomas
pump) (30A for 6 secs – blue ARB pump) roughly every 6 hours when the rate at the test orifice is set to 26
bubbles/min delivered to 10m head of water. This averages to: 20A x 30secs / (6hr x 3600secs/hr) = approx 28mA.
The total average current is therefore:
HS40 Compact quiescent
12.0mA
HS40 Compressor average
28.0mA
WL3100 average
5.0mA
Total consumption
45.0mA
A 38Ah battery will run for approx. 38Ah / 45.0mA = 844 hrs = 35 days = 1 month
(without any solar or additional charging)
The battery endurance will be dependent on the following:
§ The consumption of other equipment connected to the battery.
§ The frequency that the system wakes up to take a measurement.
§ The length of time the system is awake for each measurement.
§ The selected bubble rate – the higher the bubble rate, the more often the compressor will be required to replenish
the tank.
§ The water depth – the deeper the water, the higher the pressure in each bubble, the more air in each bubble, the
more air consumed, the more often the compressor will be required to replenish the tank.
§ The battery Ah capacity – the minimum recommended battery capacity is 38Ah.
3.5 Battery Voltage
The battery voltage is monitored during all phases of operation. If the battery voltage falls below 10.0V then all
compressor operation will stop immediately. The battery voltage must then rise above 12.0V before clearing the
battery low condition and restarting the compressor.

© 2022 HyQuest Solutions 14
Operation
A pump up cycle will be aborted if a battery low condition occurs. This condition is most likely to occur when the
compressor is on because it draws approximately 20A when operating – causing the battery voltage to drop.

© 2022 HyQuest Solutions 15
Maintenance
4Maintenance
The HS40 Compact requires little maintenance, however a yearly check of the micro-mist filter element is
recommended to ensure that moisture is being removed from the system effectively. You will also need to ensure that
your battery / power supply is sufficient for the equipment that you have installed and that both your battery and
charging system are working correctly. (See Specification page).
Note:
All fittings must be secure.
Even a minor leak will prevent the pressure from being maintained.
For more information, see the following subsections:
§ Automatic Moisture Extraction
§ Filter Maintenance
4.1 Automatic Moisture Extraction
All HS40 Compact models have a system that automatically purges any built up moisture in the micro mist separator.
As the moisture builds up, it can be seen in the green transparent bowl of the micro mist separator. As the moisture
builds, it lifts a float which allows the moisture to drip from the bowl. (An optional system (HS40AFC/3100V) can be
requested consisting of a stainless micro mist separator and a solenoid valve which automatically purges out moisture
at the end of each pump up cycle.)
15
16

© 2022 HyQuest Solutions 16
Maintenance
4.2 Filter Maintenance

© 2022 HyQuest Solutions 17
Maintenance
Note: Reverse step 4 to step 1 to re-assemble.

© 2022 HyQuest Solutions 18
Troubleshooting
5Troubleshooting
This fault finding guide should be used by the HS40 Compact user before they consult HyQuest Solutions to assist with
specific problems.
HS40 Compact Not Powering Up
§ Check battery voltage.
§ Check battery POWER and GROUND connections to the battery – make sure
they are done up tightly and there is no corrosion.
The compressor doesn’t start
when I connect the power
§ Check the state of the Condor pressure switch, and make sure it is set to the
‘1’ position.
§ The compressor should only start if the pressure is below 400kPa – or the
HS40 power was disconnected before it had reached the 750kPa level
(maybe it stopped due to battery LV, or pressure leak and then the battery
was disconnected.)
§ Check the battery voltage with your multimeter – if it is below 12V, then
maybe the controller locked out the compressor as the voltage fell below
10V, and the voltage has not yet risen above 12V to re-enable the
compressor. (Make sure the minimum battery capacity is 38Ah)
The compressor doesn’t start
when the pressure falls below
400kPa (58psi).
§ Check the state of the Condor pressure switch, and make sure it is set to the
‘1’ position.
§ Check the battery voltage with your multimeter – if it is below 12V, then
maybe the controller locked out the compressor as the voltage fell below
10V, and the voltage has not yet risen above 12V to re-enable the
compressor. (Make sure the minimum battery capacity is 38Ah)
The compressor starts but then
cuts out before 750kPa (110psi)
is reached.
§ Check the battery voltage with your multimeter – if it dips below 10V while
compressor is on, then maybe the battery condition is suspect.
§ Check the voltage on the “POS” and “NEG” stud of the controller – these
should be the same as your battery voltage – if the voltage on these studs
drops when the compressor turns on (but the battery voltage looks OK), then
you are getting a voltage drop somewhere – maybe a lose connection on the
battery – or maybe the battery leads are too long or the battery cable gauge
is not heavy enough – see section Extending the Battery Cables .
The compressor doesn’t stop at
750kPa (110psi)
§ There is a fault with the Condor pressure switch adjustment. Contact HyQuest
Solutions for the adjustment procedure.
Can I check the check the
pressure transducer calibration
through the bubble rate test
port ?
§ You may be familiar with this feature in the HS40 Series I or HS40 Series II –
but this was removed from the HS40 Compact – so the answer is no, you
cannot check the pressure transducer calibration through the bubble rate test
port!
8

© 2022 HyQuest Solutions 19
Repair
6Repair
HyQuest Solutions precision instruments and data loggers are produced in quality-controlled processes. All HyQuest
Solutions production and assembly sites in Australia, New Zealand and Europe are ISO 90001 certified. All equipment
is factory tested and/or factory calibrated before it is shipped to the client. This ensures that HyQuest Solutions
products perform to their fullest capacity when delivered.
Despite HyQuest Solutions most rigorous quality assurance (QA), malfunction may occur within or outside of the
warranty period. In rare cases, a product may not be delivered in accordance with your order.
In such cases HyQuest Solutions’ return and repair policy applies. For you as a customer, this means the following:
1. Contact HyQuest Solutions using the Repair Request Form made available online:
https://www.hyquestsolutions.com.au/fileadmin/Form/RepairRequestForm.pdf
In response you will receive a reference number that must be referenced on all further correspondence and on the
freight documents accompanying your return shipment.
2. Please provide as much information and/or clear instructions within the return paperwork. This will assist our test
engineers with their diagnosis.
3. Please do not ship the goods prior to obtaining the reference number. HyQuest Solutions will not reject any
equipment that arrives without reference number; however, it may take us longer to process.
Custom requirements for items sent to HyQuest Solutions for warranty or non-warranty repairs: Check with your
national customs/tax authorities for details, processes and paperwork regarding tax exempt return of products.
Typically, special custom tariff codes are available (such as HS Code = 9802.00) that verify the item is being returned
for repair and has no commercial value. Please note that the customs invoice / dispatch documents should also clearly
state: “Goods being returned to manufacturer for repair – No Commercial value”. It is mandatory to have any returned
goods accompanied by a commercial invoice on headed paper. HyQuest Solutions reserves the right to charge the
customer for time spent rectifying incorrect customs documents.
Note: Please ensure that your goods are packed carefully and securely. Damage that occurs during transit is not
covered by our warranty and may be chargeable.

© 2022 HyQuest Solutions 20
Technical Data
7Technical Data
Power
Operating Voltage
12 V DC Nominal
Recommended
Battery
12 V DC Sealed Lead Acid (38 Ah)
Low Battery cut-out
10 V DC
Battery recharge
recovery
12 V DC
Maximum battery
voltage
14.4 V DC
Operation Range
§ Up to 40 m (130ft) of water pressure head
§ (Special request: up to 50 m (160ft) of water pressure head)
Electronics Quiescent
12 mA (HS40AFC) + 5 mA (WL3100)
Compressor Current
20 Amps for 30 secs every 6 hrs (black Thomas compressor)
26 bubbles/min @ 10mH20) (averages to about 28mA)
(Previous blue ARB compressor drew 30A)
Average battery
consumption
45 mA (with bubble rate set to 26 bubbles/min @ 10 mH20)
Solar
A small 10 Watt solar panel is sufficient to keep the battery fully charged
Maximum Tank /
Purge Pressure
750 kPa (110 psi) [±20 %]
Minimum Pump /
Purge Pressure
400 kPa (58 psi) [±20 %]
Differential Pressure
Regulator
20 kPa to 35 kPa (3 psi to 5 psi)
Bubble Rate
Adjustable from 0 to 45 bubbles / min
Transducer Pressure
Connection
1/4 inch tube
River Line Connection
3/8 inch tube (or optional 1/4 inch tube), Dual orifice (2) × 3/8 inch tube (or optional 1/4
inch tube)
Max River-line Length
200 m (600 ft) using 3/8 in OD and 1/8 ID tubing