STIEBEL ELTRON MINI 3

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Summary

Temperature Increase Specifications

Electrical Connection Procedures

Overview

The Stiebel Eltron Mini™ 3, Mini™ 4, and Mini™ 6 are tankless electric water heaters designed for various applications, including hand washing in commercial/industrial facilities and homes, kitchen areas, photo developing shops, and laboratories. They can also be used for whole apartments and homes in warm climate zones where ambient water temperatures are higher. Unlike conventional storage-type water heaters, the Mini™ units do not store hot water. Instead, they heat water instantaneously as it flows through the unit. Powerful heating elements are activated by a flow switch when water is drawn from a hot water faucet connected to the Mini™. This design eliminates standby losses, making the Mini™ more energy-efficient than storage-type water heaters. As long as the faucet is open, the unit will continuously supply hot water.

The temperature of the hot water delivered by the Mini™ depends on several factors: the wattage of the heating element, the temperature of the incoming cold water, and the water flow rate through the unit. To ensure proper operation, the Mini™ must be carefully matched to its intended application. For any questions regarding the planned use of the Mini™, customers are encouraged to contact Stiebel Eltron's technical service line.

Installation of the Mini™ units must be carried out by a licensed electrician and a licensed plumber. It is crucial to read the entire manual carefully before attempting installation. Failure to follow safety rules or instructions can lead to improper operation, property damage, serious bodily injury, or even death. Stiebel Eltron, Inc. will not be liable for damages resulting from non-compliance with installation and operating instructions or improper use. Improper use includes heating any liquid other than water. Any such failure or improper use will void the warranty. The unit's plastic cover should never be removed unless the electricity is turned off.

For mounting, the unit must be installed with the plumbing connections pointing downward or upward. It should not be installed in areas where it would routinely be splashed with water, as this could result in electric shock. The Mini™ should be installed as close as possible to the hot water draw-off point, such as directly underneath a sink or next to a shower stall. It must also be installed in a frost-free area; if freezing temperatures are expected, the unit should be removed beforehand. A minimum of 5 inches of clearance on all sides is required for servicing. To mount the unit, the plastic backplate is removed by unscrewing the left and right screws and pulling on the tab with a screwdriver. The backplate is then securely mounted to the wall using two screws through the designated mounting holes. Finally, the unit is snapped back into the backplate, and the two screws are reinstalled.

Regarding water connections, if soldering is necessary near the unit, the flame must be directed away from the housing to prevent damage. All plumbing work must comply with national and applicable state and local plumbing codes. Excessive heat from soldering on copper pipes near the Mini™ can cause damage. A pressure reducing valve must be installed if the cold water supply pressure exceeds 150 PSI (10 bar). Before connecting, the cold water supply line must be flushed to remove any scale and dirt. An isolating valve should be installed in the cold water line to allow the unit to be isolated for maintenance. When the plumbing connections face downward, the cold water connection (inlet) is on the right side of the unit, and the hot water connection (outlet) is on the left side. Tankless water heaters like the Mini™ are not required to have a Pressure and Temperature Relief Valve, but if local inspectors demand one, it should be installed on the hot water outlet side. The Mini™ is designed for installation using two 3/8-inch OD tube outlets. After all plumbing work is completed, it is essential to check for leaks and take corrective action.

For electrical connections, it is paramount to turn off the main breaker panel switch before beginning any work to avoid electric shock. All mounting and plumbing must be completed before proceeding with electrical hook-up. Where required by local, state, or national electrical codes, the circuit should be equipped with a ground fault interrupter. Failure to electrically ground the unit can result in serious injury or death. The Mini™ 3 operates on 110-120V, while the Mini™ 4 and Mini™ 6 operate on 208V, 220-240V. Installing a Mini™ 3 on a 208V or 220-240V circuit will destroy the heating element, and this is not covered under warranty. All electrical work must comply with national and applicable state and local electrical codes. The Mini™ should be connected to a properly grounded dedicated branch circuit of the correct voltage rating. In installations with multiple Mini™ units, each unit requires an independent circuit. The "pigtail" must be fed into the electrical junction box, and wires are fed through a strain relief clamp, which is then tightened. The live wires (L/L or N/L) are connected to the black and brown wires on the unit's "pigtail," and the ground wire is connected to the green/yellow wire. The unit can also be installed using an outlet and plug with the correct voltage and amperage rating.

Before putting the water heater into operation, open the hot water faucet for a few minutes until water flow is continuous and all air is purged from the water pipes. The unit's plastic cover must be installed before the circuit breaker is turned on. Air in the cold water pipe can destroy the bare-wire heating system of the Mini™. If the water supply to the Mini™ has been interrupted (e.g., due to frost risk or work on water pipes), the following steps must be carried out before using the system again: turn off the circuit breaker or unplug the unit, open a hot water tap downstream of the device until the device and cold water pipe are free of air, then turn on the circuit breaker or plug the unit back in.

Users should be instructed on the function of the unit and familiarized with its use. Important instructions include drawing attention to possible hazards (scalding, electrical shock) and handing over these instructions for future reference. To obtain proper temperature control at a single spout mixer-type faucet, restrict cold water flow by partially closing the cold water shut-off valve under the sink until cold water and hot water flow rates are approximately the same.

Stiebel Eltron Mini™ tankless heaters are designed for a very long service life, though actual life expectancy will vary with water quality and use. The unit itself does not require any regular maintenance. However, to ensure consistent water flow rate, it is recommended to periodically remove scale and dirt that may build up at the aerator of the faucet or in the shower head. Additionally, the Mini™ has a built-in filter screen that should be cleaned from time to time. To do this, turn off the cold water supply at the isolating valve, unscrew the cold water connection, clean the screen, and put it back into its original position. Other than the filter screen, the Mini™ does not contain any parts serviceable by the layperson. In case of malfunction, a licensed plumber or electrician should be contacted.