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Garnet 709 SeeLevel II 3-Tank Monitoring System, Battery, Fresh, Grey, Black + LPG, External Sensors

Garnet 709 SeeLevel II Tank Monitoring System
Garnet SeeLevel II Tank Monitoring System
 
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List Price: $260.11
: $249.96
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Part Number: 709-System
Manufacturer: Garnet Instruments

Quantity in Stock :15

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Garnet SeeLevel II 709 Tank Monitoring System – 3 Water Tanks + LPG
The original SeeLevel II upgrade! The Garnet 709 monitors fresh, grey, and black water tanks PLUS your propane (LPG) level – all with precise percentage readouts instead of vague 1/4, 1/2, 3/4 guesses. External sensors mount outside your tanks, eliminating the fouling and false readings that plague traditional probe-style monitors.

Overview

The Garnet 709 SeeLevel II is the ideal upgrade for RVers who want accurate tank AND propane monitoring without adding a pump switch. This base model monitors three water tanks (fresh, grey, black) plus your LP gas level – perfect for replacing that frustrating factory monitor that always shows "full" on your black tank. Unlike the 709-P3 (which has a pump switch but no LPG), the 709 connects to your RV's existing propane sender for complete system monitoring.3 TanksLPG Monitor% Readout

📊 Percentage Display

0-100% accurate readouts

🔧 External Sensors

No fouling, no false readings

⛽ LPG Monitoring

Uses existing propane sender

🔋 Battery Monitor

Voltage readout included

📋 Not Sure Which SeeLevel Model You Need?

With multiple models available, choosing the right SeeLevel II system can be confusing. Use our SeeLevel II Comparison Guide to find the perfect match for your RV's tank configuration and feature requirements.

📍 Add a Second Display – Monitor From Anywhere!

One of the best features of the SeeLevel II system is the ability to add additional monitors at other locations in your RV. The common bus wiring allows you to connect multiple displays to the same sensor network.

Popular second display locations:
• Bedroom or bathroom for overnight monitoring
• Outside water bay for convenient dumping
• Cockpit/living area for quick checks
• Near the galley for water conservation awareness

Simply purchase an additional 709 Monitor Only and wire it to your existing sensor network – no additional sensors needed!

Why SeeLevel II Outperforms Factory Monitors

Traditional RV tank monitors use probes that extend inside the tank. These probes quickly become coated with waste residue, toilet paper, and struvite buildup – causing the dreaded "always shows full" problem that plagues nearly every RV owner.

The SeeLevel II difference: Sensors mount externally on the tank wall using 3M adhesive. They measure tank levels through the plastic tank wall using capacitive sensing technology. No probes inside the tank means:

  • No fouling: Sensors never contact tank contents
  • No false readings: Accurate levels regardless of tank condition
  • No maintenance: Install once and forget it
  • Better accuracy: ±⅜" precision vs. vague quarter-tank guesses

✅ What the 709 Monitors

Battery Voltage: Know when batteries need charging
Fresh Water Tank: Know exactly how much water remains
Grey Water Tank: Plan showers accordingly
Black Water Tank: Know exactly when to dump – no guessing
LPG/Propane Tank: Monitor propane level via existing sender

LPG/Propane Monitoring – How It Works

The 709 connects to your RV's existing propane tank sender (the sensor built into your LP tank gauge). It does NOT include a propane sensor – it uses the one already installed in your RV.

  • Most RVs with permanent/built-in propane tanks have a sender already installed
  • Look for wiring from your tank's dial gauge (often called "LPG gauge sensor" or "remote ready dial")
  • Portable DOT cylinders (20lb BBQ-style tanks) typically do NOT have senders
  • Calibrate by filling tank and pressing LPG + BATT buttons simultaneously for 5 seconds

⚠️ Need a Pump Switch?

The base 709 model does NOT include a water pump switch. If you need a pump switch:

709-P3: 3 tanks + pump switch (no LPG)
709-P3W: 3 tanks + pump switch + LPG
709-BTP7: 3 tanks + pump switch + LPG + Bluetooth

Choose Your Sensor Size

Garnet offers three sensor sizes to match your tank heights. Sensors can be cut shorter or stacked for taller tanks:

Sensor Length Resolution Ideal Tank Height
710-AR2 9" 0.25" 3.5" – 10.5" (single)
Up to 19.5" (stacked)
710-ES3 12" 0.33" 4.5" – 14" (single)
Up to 26" (stacked)
710-SS2 16" 0.44" 7" – 18" (single)
Up to 34.5" (stacked)

Tip: The 710-ES3 (12") is the most popular choice and fits most standard RV tanks. Do NOT mix sensor types when stacking.

🚫 Plastic Tanks Only

SeeLevel II sensors work on plastic/polyethylene and fiberglass tanks only. They will NOT work on metal tanks. Tank walls must be 3/8" (10mm) thick or less.

Installation Overview

Most RV owners can install the SeeLevel II system themselves. The hardest part is accessing your tanks – the actual installation is straightforward:

  • Plan installation: Identify tank locations and measure tank heights
  • Clean tank surfaces: Sensors adhere with 3M adhesive – surfaces must be clean and dry
  • Trim sensors to length: Cut sensors to match tank height (cut between segments)
  • Mount sensors: Adhere to outside of tank wall, near bottom
  • Run wiring: Connect sensors via 2-wire bus (can often reuse existing wiring)
  • Connect LPG: Wire green LPG wire to existing propane tank sender
  • Install display: Mount display panel in desired location
  • Program sensors: Simple tab-clipping identifies each sensor to the system
  • Calibrate LPG: Fill propane tank, then press LPG + BATT for 5 seconds

Complete installation instructions included. For detailed guidance, download the SeeLevel 709 Manual (PDF). Professional installation recommended if you're uncomfortable with electrical work.

Built-in Diagnostics

The SeeLevel II includes diagnostic capability that allows you to check the operating characteristics of each sensor. If a sensor develops a problem, the display can show you the signal level and help identify the issue.

Quick Reference

Model709
SeriesSeeLevel II
Tanks Monitored3 (Fresh, Grey, Black)
LPG MonitorYes – via existing sender
Battery MonitorYes – Voltage readout
Pump SwitchNo (see 709-P3 or 709-P3W)
Display Type3-digit LED
Accuracy±⅜" (±10mm)
Resolution⅜" (10mm) increments

Electrical Specifications

Operating Voltage11V – 16V DC
Nominal Voltage12V DC
Current Draw< 200 mA
Fuse Rating10 Amps max
Wiring2-wire common bus

Display Dimensions

Panel Size4"W x 2.8"H x 1"D
Cutout Size3"W x 1.8"H

What's Included

✓ 709 Display Panel
✓ Wiring pigtail/harness
✓ (3) Sensor boards (choose size at checkout)
✓ Installation instructions

🔌 Add a Second Monitor!

Want to check tank levels from the bedroom, bathroom, or wet bay? Simply add a 709 Monitor Only to your system. Multiple displays can share the same sensors via the common bus wiring – no additional sensors required!

Sensor Options

710-AR2 (9")Best for low-profile tanks 3.5"-10.5"
710-ES3 (12")Most popular – fits tanks 4.5"-14"
710-SS2 (16")For taller tanks 7"-18"

Sensors can be stacked for taller tanks up to 34.5". Do NOT mix sensor types when stacking.

Related 3-Tank Models

7093 tanks + LPG (this model)
709-P33 tanks + pump switch (no LPG)
709-P3W3 tanks + pump switch + LPG
709-HP3W3 tanks + pump + heater + LPG
709-BTP73 tanks + pump + LPG + Bluetooth

→ View Complete SeeLevel II Comparison Guide

📄 Documentation

Manual: SeeLevel 709 Manual (PDF)
Support: garnetinstruments.com/support
Warranty: 1 Year Limited

Seelevel 709 Monitoring System
Seelevel 709 Tank Sensor Installation

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