Bosch Wireless Remote Control TSTAT2

The Bosch Wireless Remote Control TSTAT2 for the Bosch AquaStar 2700ES / 2400ES / 2400E / 2400EO / 250SX / 250SXO allows you to program your Bosch tankless gas water heater to a comfortable and safe temperature from around your home from a distance of up to 98 ft.

The TSTAT2 remote is particularly useful if you own a jacuzzi or hot tub that requires a hotter water temperature than you normally desire for regular shower use.

Please note that the electrical control of the Bosch AquaStar 2700ES / 2400ES / 2400E / 2400EO / 250SX / 250SXO must be removed and opened in order to install the wireless receiver circuit board to enable the use of the TSTAT2 Wireless Remote Control.

The Newer Bosch models, 2700ES and Bosch 2400ES tankless water heaters have been redesigned to make the installation of the wireless receiver circuit board much easier. The circuit board is basically a plug and play unit.

The TSTAT2 controls the temperature of your water heater and does not have a reset button.   If the heater has an error then a code will be on the display of the heater and the user has to go to the heater to reset it from there and should document the error and then see if it returns after resetting.

The TSTAT2 Wireless Remote Control for Bosch 2700ES / 2400ES /2400E / 2400EO / 250SX / 250SXO features the following:

• LCD displays temperature, error codes and functions
• Temperature measured in °C or °F
• Low battery level indicator
• 98 feet user range
• Alkaline AA LR6 2x1.5V battery power 915 MHz
• Security lock function
• IP X6 Protection
• Priority function - temperature cannot be modified by other user interface when water is running

Don't forget to periodically change the two AA batteries in your Bosch wireless TSTAT2 thermostat as they will certainly corrode over time. The batteries in TSTAT2 thermostats that are kept in bathrooms will corrode faster than in other less humid environments, such as kitchens. Your batteries should be checked yearly for any signs of corrosion and replaced every five years in any case.

Freeze Protection for Bosch Gas Tankless Water Heaters

Most all of the Bosch gas tankless water heaters come with built in freeze protection.  The heaters listed below have built in freeze protection and are approved to be installed in some outside installations.

Our Bosch Outdoor Tankless Water Heaters (Bosch 2700ES with AQOK Outdoor Cap / Bosch 2400ES with AQOK Outdoor Cap/ 125BO / 425HNO / 2400EO / 250SXO) have built in freeze protection and are designed to handle an occasional overnight freeze. They plug directly into the wall and provide freeze protection down to 5 deg F above zero. In order for the freeze prevention kit to provide adequate protection,120V AC must always be supplied to the water heater.They are approved for use in the following areas:


Florida, Georgia, North Carolina, South Carolina, Alabama, Mississippi, Arkansas, Texas, Virginia (only in zip codes beginning with the first three digits 233-237), Arizona (in zip codes beginning with the first three digits 850-857 and 864), Oregon (in zip codes beginning with the first three digits 970-975), Washington (in zip codes beginning with the first three digits 980-986), California (except in zip codes beginning with the first three digits 935 or 961).

Installation instructions state that the water heaters must not be installed in a location where it may be exposed to prolonged freezing temperatures. If the heater must be left in a space which is likely to experience prolonged freezing temperatures, all water must be drained from the heater.  If precautions are not taken, resulting damage will not be covered under the warranty. NOTE: Use of agents such as anti-freeze is not permitted as they may cause damage to the water heater's internal components.  The freeze prevention will not protect plumbing outside the appliance from freezing. Precautions should be taken.

The Bosch 250SX/2400E/2400ES and 2700ES come with built in freeze protection and these units are for inside installation only.  The freeze protection helps the unit if it is installed on the inside of an outside wall where it may be cooler than normal.

Bosch AquaStar 2700ES vs. Bosch Evolution 500 Tankless Water Heaters

The Bosch AquaStar 2700ES is Bosch's top-of-the-line 199,000 BTU retail tankless water heater. As a retail tankless water heater the Bosch 2700 ES can be sold directly to home owners and is the perfect water heater for Do-it-yourselfers (DIY).

The Bosch 2700ES is available in both natural gas (Bosch 2700ES-NG) and liquid propane (Bosch 2700ES-LP). The 2700 ES direct vent tankless water heater requires special 3" or 4" stainless steel vent pipe and can be vented either through the roof or out the side wall. In approved areas the 2700ES can also be mounted outdoors as it comes with freeze protection that is good down to 5 degrees F above zero and provides protection against occasional overnight freezes.

In addition to coming with built-in freeze protection, the AquaStar 2700ES also comes with a pressure relief valve (PRV) and an external water filter.

The Bosch Evolution 500 is identical to the Bosch AquaStar 2700ES. It also comes in natural gas (Bosch Evolution 500 NG) and liquified petroleum (Bosch Evolution 500 LP) models. As a heater in Bosch's professional line of tankless water heaters, however, the Bosch Evolution 500 can only be sold to licensed installers or builders. As a Bosch Professional heater the Evolution 500 comes with a 15 year warranty on the heat exchanger and 5 years on all other parts.

Like the 2700ES, the Evolution 500 direct vent tankless water heater also comes with built-in freeze protection, a PRV and an external water filter. It requires the same Z-Flex Z-Vent 3" or 4" special stainless steel vent pipe.

So, if you intend to have your tankless water heater installed professionally, have your installer visit www.prowaterheatersupply.com and check out the Evolution 500. These heaters are specially priced while supplies last.