The SeeLevel recreational vehicle tank monitoring system has been, for quite a while now, the leading digital display system on the market. Other systems have been introduced, but none with the accuracy, features, and ease of installation of the SeeLevel. I've been such a fan of it that I have recommended it be installed in family and friends coaches as well having it in each of our previous motorhomes.
Garnet Instruments who are the manufacturers of the system has 15 years of electronics design and manufacturing experience in producing liquid level monitoring systems. Their systems are utilized a range of monitoring systems from tanker truck applications to stationary tanks, to RV applications using 2 different technologies in the SeeLevel product line-up. Being in the electronics design and manufacturing industry myself, I recognize the quality in their circuit boards design both on the rigid display panel as well as the flex circuitry used for the sensor strips.
Having previously always installed the economical Model 709
which monitors 3 holding tanks as well as propane tanks, I opted in our new Allegro Bus motorhome to install the advanced Model 713
system. The 709 system I previously installed,( Winnebago Journey Installation
) is a more economical system due to smaller sensors and a slightly lower resolution but it is still an excellent system. The Model 709 is available with a selection of configurations with switches to control the water pump and hot water heater if desired. The models 711
, and 713
systems use longer 16 inch sensors with smaller sensing pads for a slightly better resolution. The Model 713 which I installed is unique in that it is constantly monitoring each of the holding tanks as well as the external temperature via a remote sensor and constantly displaying that information on the displays. According to the manufacturer, the 713 has special anti collision software to allow each console to update every 5 seconds without conflict. The 713 also offers an optional 744 AIM module, which is a D/A converter module that produces a 0-5vdc for integration to the Monaco Aladdin system or a Silverleaf monitor. In my case, I elected to go with the 713 system since with our family of 5, the full time display of tank data would be handy and I liked the temperature display as well. I opted to install a second display console in the service bay. While I did not install the model 713CC or 713FT with the propane tank level monitoring, that choice is also available as well as the display panel being available in either red or green characters.
The basic process of installing the system is similiar for the entire product line of SeeLevel systems, and can be followed regardless of model chosen. The sole installation difference between the 709 and higher level systems is that the 709 uses a common buss wiring system, meaning all senders are wired in parallel, versus the other models requiring their own individual circuit for each tank and temperature sensor. Installing the SeeLevel in our Allegro Bus 43QRP was a Saturday morning project and a typical installation can be completed by the do-it-yourselfer within a few hours depending on how easy you can access the tanks and feed wires to your desired display location.
The SeeLevel kit comes complete with everything required for installation other than hookup wire to run from the tanks locations to the display panels as that wire length depends on your particular motorhome. It should be noted here that the existing wiring can be re-used for all models of SeeLevel if desired.
The photograph belowshows the 3 level sensing strips, a display panel for installation inside the coach as well as an additional panel for the water bay, and the temperature sensor module and two harnesses that plug into the back of the display consoles.
After checking the parts, and reviewing the installation manual, it was time to access the motorhome freshwater and holding tanks. Tiffin, like most motorhome manufactures, installs the tanks in the motorhome behind a removable panel on the motorhome side wall. After simply removing the 4 screws holding that panel and setting it safely aside, the fresh, grey and black water tanks are all visible.
The Allegro Bus 43QRP has a freshwater tank which is slightly tapered with the taller side being on the passenger side and the shorter side being on the driver side. This wedge shaped freshwater tank allows the black and grey tanks to also be wedge shaped in the opposite direction so that they are tilted to the driver side to facilitate complete draining. The tank layout may have a slightly different configuration in various other models or floorplans.
Since I wanted to measure the complete height of the water in each tank, I elected to install the freshwater sender on the passenger side where the freshwater tank was the maximum height. Next we installed the black and grey water sensors on the driver side where they were correspondingly taller. It should be noted that some models of Tiffin do not allow easy access to the driver side due to the water heater exhaust outlet placement on that door so all of the sensor strips must be placed on the passenger side.
Installation of the sensors requires finding an unobstructed area of the tank where the sensors can be mounted with no ferrous metals lying over the face of the sender within 1.5 Ė 2.0 inches of the sensor. It is also important to mount the sensors away from flanges or corners of the tank where the thickness variations of the tank can interfere with the fluid height readings. After carefully measuring the height of the tank, the sensor strips lengths are cut to the nearest inch which corresponds to the tank height less about 1 inch. In this way, the sensor top and bottom should be a minimum of one half of an inch or so from the top and bottom of the tanks. Cutting of the sensor strips is done between the sensor pads with a pair of common scissors.
The freshwater tank has a convenient location that is clear of all metal in the rear corner of the tank. Prior to placing the strip, it's suggested to lightly sand the surface of the tank to smooth any molding bumps to allow the sensor to make full contact with the tank. After sanding, a quick wipe with some acetone or alcohol removes any possible dust and oil contamination to prepare the surface for excellent adhesion. For testing purposes you should first duct tape both sides of the sender to the tank. This temporary application of the sensor permits operating the system and fine tuning the sensor position if desired. Finally, after checking the system operation, the sensor is permanently applied to the tank in the chosen location by removing the adhesive backing paper and pressing it firmly against the tank. In the photo, it is clear that the strip has been cut to a seven inch length and is centered on the side of the tank.
On our 43QRP, the black and grey holding tank sensors are applied in the identical manor but on the driver side of the motorhome. Photographs of those sensors is difficult in that the tanks are behind the water board, but the tanks are actually fairly easy to reach by removing the plastic cover above the water board and in my case enlisting the help of my son in reaching behind the water board from the top to position the sensors while I checked the alignment from underneath the board and pressed them into place.
The final sensor to be installed is the external temperature sensor. This device is a small waterproof encapsulated cube shown in the first photograph of the installation kit which can be fastened anywhere on the exterior of the coach to monitor the outside temperature, or alternatively, some owners install the temperature sensor in the tank area to monitor freezing threats. For my installation, I wished to monitor the outside air temperature so, I simply drilled a small hole in the bottom of the compartment right next to the freshwater overflow pipe. The temperature sensor is fastened to the overflow pipe underneath the coach and the wiring passed up through the hole into the compartment before sealing the hole with RTV.
Since each sensor has only 2 wires and one of the wires is a common ground, the grounds are all tied together and run to the ground connection on the display panel. Each signal wire from the sensors are individually run to the display panel connector as well and fastened to the appropriate color coded wire on the harness. In my installation, I used 2 conductor jacketed wire for each of the black and grey sensors running those wires from the driver side of the coach to the passenger side where I connected those wires as well as the freshwater sensor and temperature sensor to a 6 conductor color coded wire to feed the display panels. 12 volt DC power and ground are required at each display panel location as well which is easily run using a 2 conductor power wire. In my case, I used the same grey jacketed wire as I used to for the black and grey tank sensors.
Below, you can see the completed sensor wiring including those wires to the temperature sensor that is under the compartment floor. All of the wiring is fed up through the existing access hole in the floor of the motorhome and into the living quarters. The sensor wires should be secured in place with wire ties to prevent excess movement and prevent them from moving in front of the sensors where they could affect the accuracy.
After having the sensors installed, the next step is mounting the display panels and completing the necessary wire connections between the sensors and displays. I wanted the interior display panel installed in the hallway of the coach directly underneath the solar panel charging indicator and light switches. Typically, in a motorhome installation, adding additional equipment near a manufacturer installed electrical item means that there is a wiring chase available for us. In the Allegro Bus, there exists such a chase inside the bathroom where the vent stack is run from the holding tanks to the ceiling. That chase provided an easy access route to run the wiring to under the vanity and to the sensors.
Cutting the hole into the hallway wall can be done utilizing a jigsaw or I find a Rotozip type tool works very well. Since the display panels are designed with removable color coded harnesses that plug into them, it is very easy to connect the various wire ends to the harness then only attach the harness to the display and insert it into the precut hole. The interior display panel looks nice in the hallway and since it displays the tank volume and outside temperature continuously provides a constant awareness of the water situation and temperature.
The final step to the installation is filling all of the tanks to at least one third of their capacity and applying power to the system. Both of the display panels continuously indicate the level of liquid in the tanks and as we ran water we could actually watch the displays show the transfer of water from the fresh water tank to the other two holding tanks. As you can see, we've pumped most of the water from the fresh water tank to the other 2 holding tanks and it's a balmy 51 degree March day in Pennsylvania.
The additional display panel is wired in the identical fashion and mounted directly to the water board panel outside the motorhome in the sewer bay. It provides a convenient location to monitor the tanks when dumping or refilling the freshwater tank.
The SeeLevel system has to be the number one improvement in recreational vehicle systems available on the market. In my personal opinion, it should be installed as an OEM item on units, but I would certainly recommend it as the first aftermarket item any motorhome owner installs.