Serial Number Cutoff for Logic PCB for Bosch Tronic 6000C WH17 & WH27

Bosch Thermotechnology is always upgrading the Bosch tankless water heaters and has recently updated the Bosch Tronic WH17 & WH27.  The new model numbers for these heaters are:

Bosch Tronic 6000C WH17 - Model #45-551721

Bosch Tronic 6000C WH27 - Model #45-557721

There have been several upgrades to the units and one of theses changes is to the Logic Printed Circuit Board (PCB).  The new Logic PCB for the Bosch Tronic 6000C WH17 & WH27 has a different part number from the older units.  Below is the new part numbers and also the serial number cutoff for the PCB boards.

Serial Number Cutoff:

WH17
Logic PCB #8-738-710-921, this would be for any new 6000C WH17 with serial number 555 A 800001 or higher

WH27
Logic PCB #8-738-710-922, this would be for any new 6000C WH27 with serial number 555 A 800271 or higher

CZM100 Zoning module for Bosch Greenstar Boilers

Global Protankless Supply now carries the CZM100 Zoning module.  This zone controller is used for the Bosch Greenstar Boilers so that you can control multiple zones of heating off 1 Greenstar Boiler.  Three zone control module, for circulator pumps or zone valve activation. The sleek, compact zone control module is expandable up to three modules, providing a maximum of 8 heating zones. It features external front-facing LED lights for operational visibility.

The CZM100 Comfort Zone Manager provides a fixed warm weather shutdown function at 70F when used with a CRC100 and is adjustable with the CRC200. An optional outdoor sensor is required for warm weather shutdown function.

New Bosch Tronic 6000C WH17 & WH27 Electric Tankless Water Heaters

Global Protankless Supply is now carrying the new Bosch Tronic 6000C series model WH17 & WH27 electric tankless water heaters.  Bosch is always making improvements and upgrades to the tankless water heaters.  The Bosch Tronic 6000C WH17, part number 7736503050 and the Bosch Tronic 6000C WH27, part number 7736503051 now come with a temperature control knob on the front of the unit and also a digital display to show the set temperature. The new Bosch Tronic 6000C WH17, model number 45-551721 begins with serial number 555 A 800001.  The new Bosch 6000C WH27, model number 45-557721 begins with serial number 555 A 800271.

Bosch has made other upgrades to the unit and some of the highlights of the new units are listed below.

• Provides endless hot water for 1-3 major applications at a time*
• 97 % efficiency rating
• Compact & lightweight
• Electronic flow sensor
• Element modulation provides a constant output temperature
• Filter screen on inlet
• Improved temperature stability & control
• Enhanced scale resistance

*Dependent on location and model used.

The Bosch WH17 needs to be wired in using 8 ga wire to 2 - double pole 40 amp breakers and the home should be equipped with at least a 150 amp panel box.

The Bosch WH27 needs to be wired in using 8 ga wire to 3 - double pole 40 amp breakers and the home should be equipped with at least a 200 amp panel box.

There is a 5 year warranty on the heating elements and 2 year warranty on all other parts.

Below is a sizing chart that may help determine which model electric tankless may be best for you in the area where you live.

Items Included with Bosch Greenstar Floor-Standing (FS) Boilers

This is to list the items that are included with the Bosch Greenstar Floor-Standing (FS) Straight Boilers and FS Combi Boilers.  The Bosch Greenstar FS boilers already have the main controller integrated into the top of the boiler itself.  See the list below of the items that come with the boilers and also the list of the optional accessories.

Included with Bosch Greenstar FS Straight Boilers
Installation manual
Adapter for connection of a Low Water Cutoff (LWCO)
Gas conversion kit
DHW tank temperature sensor (for use with indirect tank)
Flue adapter

Included with Bosch Greenstar FS Combi Boilers
Installation manual
Adapter for connection of a Low Water Cutoff (LWCO)
Gas conversion kit
Flue adapter

Optional Accessories for Greenstar FS Boilers (not included)
FW200 Weather compensation control
CRC100 or CRC200 room thermostats
CZM100 Zoning module
Optional concentric vent kit available for horizontal direct vent terminations
ICM control for cascading up to 4 boilers

New Bosch CT100 Wi-Fi Enabled Smart Thermostat Control

Global Protankless Supply is pleased to announce that Bosch is now making a CT100 Wi-Fi enabled smart thermostat for all the Bosch Greenstar wall-hung and floor standing straight boilers and combination boilers.  The Smart control is also good for the Buderus GB142, GB162 series condensing boilers.  The Bosch Control CT 100 connects to your boiler’s EMS BUS connection only. Therefore it can only be used for installations with a single zone. The CT100 wi-fi enabled smart controller cannot be used with the Bosch CZM100 Zone Manager to control multiple zones.

*  Bosch CT100 Thermostat Smart Control #7736700988
*  Back Plate for Bosch Smart Control #87377041690

Bosch Smart Control combines a touch screen programmable thermostat with Wi-Fi connectivity and intuitive free mobile App to allow busy households to monitor and adjust home comfort and energy consumption while on the go. Bosch CT100 can monitor and adjust home heating and hot water conditions, boiler design settings and even energy consumption via mobile App anywhere in the world via a Wi-Fi or cellular connection.

Features & Benefits:
*  Communicates with Bosch Greenstar, Buderus GB142, GB162 series condensing boilers; not just On/Off control
*  Easy to Install - 2 wire installation (use existing wires)
*  Controls space heating and domestic hot water
*  Electrically powered by Bosch boiler
*  Remote control from anywhere in the world
     o Connects to home WiFi network
     o Confidentially stores data
     o Self-learning functionality
*  Free Apple or Android App (up to 5 mobile users per control)
*  Product registration via App
*  Change home and away times with intuitive scheduling
*  Set energy goals with gas usage data Informative “How to Videos” in App and online

Please call Global Protankless Supply to with further questions and to order this product at 866-289-4652.

Bosch Replacement Parts Now on Global Protankless Supply Website

Global Protankless Supply has Bosch replacement parts available on our website.  We stock most all heat exchangers, PCB control boards for Powerstream Pro and Powerstar electric tankless water heaters, watervalves, Ariston parts such as anode rods, repair kits and more.  Please visit our website at www.prowaterheatersupply.com or call us at 866-289-4652 for further questions or to place your order.

Turn Down Ratios for Bosch Greenstar Straight & Combi Boilers

The turn down ratio can be calculated by dividing the input rating by the minimum input. See below for the appropriate turn down ratio for each boiler in the Greenstar series. The figures outlined in this bulletin are calculated using NG inputs and rounded to 2 decimal places.

Turn down ratios for Greenstar Condensing Combination (Combi) Boilers:

Bosch Greenstar Wall-Hung Combi 100 - ZWB28-3A23S3123

•    Part number: 7738 100 002
•    Input Rating: 100,800 BTU
•   Minimum Input: 24,600 BTU
•    Turndown Ratio: 4.1 : 1

Bosch Greenstar Floor-Standing (FS) Combi 100 - KWB28-3A23S3123

•  Part number: 7-733-600-082
•  Input Rating: 100,800 BTU
•  Minimum Input: 24,600 BTU
•  Turndown Ratio: 4.1 : 1

Bosch Greenstar Wall-Hung Combi 131 - ZWB35-3A23S3123

• Part number: 7738 100 256
• Input Rating: 131,900 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 3.7 : 1

Bosch Greenstar Floor-Standing (FS) Combi 131 - KWB35-3A23S3123

•  Part number: 7-733-600-083
•  Input Rating: 131,900 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 3.7 : 1

Bosch Greenstar Wall-Hung Combi 151 - ZWB42-3A23S3123

•  Part number: 7713 331 041
•  Input Rating: 151,600 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 4.2 : 1

Bosch Greenstar Floor-Standing (FS) Combi 151 - KWB42-3A23S3123

•  Part number: 7-733-600-084
•  Input Rating: 151,600 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 4.2 : 1

Turn down ratios for Greenstar Condensing Straight Boilers:

Bosch Greenstar Wall-Hung 57 - ZBR16-3A23S3123

•  Part number 7712 231 416
•  Input Rating: 57,200 BTU
•  Minimum Input: 12,900 BTU
•  Turndown Ratio: 4.4 : 1

Bosch Greenstar Floor-Standing (FS) 57 - KBR16-3A23S3123

•  Part number 7-733-600-077
•  Input Rating: 57,200 BTU
•  Minimum Input: 12,900 BTU
•  Turndown Ratio: 4.4 : 1

Bosch Greenstar Wall-Hung 79 - ZBR21-3A23S3123

•  Part number: 7738 100 322
•  Input Rating: 79,200 BTU
•  Minimum Input: 24,600 BTU
•  Turndown Ratio: 3.2 : 1

Bosch Greenstar Floor-Standing (FS) 79 - KBR21-3A23S3123

•  Part number: 7-733-600-078
•  Input Rating: 79,200 BTU
•  Minimum Input: 24,600 BTU
•  Turndown Ratio: 3.2 : 1

Bosch Greenstar Wall-Hung 100 - ZBR28-3A23S3123

•  Part number: 7712 231 415
•  Input Rating: 100,800 BTU
•  Minimum Input: 24,600 BTU
•  Turndown Ratio: 4.1 : 1

Bosch Greenstar Floor-Standing (FS) 100 - KBR28-3A23S3123

•  Part number: 7-733-600-079
•  Input Rating: 100,800 BTU
•  Minimum Input: 24,600 BTU
•  Turndown Ratio: 4.1 : 1

Bosch Greenstar Wall-Hung 131 - ZBR35-3A23S3123

•  Part number: 7712 231 414
•  Input Rating: 131,900 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 3.7 : 1

Bosch Greenstar Floor-Standing (FS) 131 - KBR35-3A23S3123

•  Part number: 7-733-600-080
•  Input Rating: 131,900 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 3.7 : 1

Bosch Greenstar Wall-Hung 151 - ZBR42-3A23S3123

•  Part number: 7712 231 413
•  Input Rating: 151,600 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 4.2 : 1

Bosch Greenstar Floor-Standing (FS) 151 - KBR42-3A23S3123

•  Part number: 7-733-600-081
•  Input Rating: 151,600 BTU
•  Minimum Input: 36,000 BTU
•  Turndown Ratio: 4.2 : 1

Bosch Greenstar Floor Standing (FS) Combi & Straight Boilers

Global Protankless Supply is pleased to announce the highly anticipated Greenstar Floor Standing (FS) series boilers. The Greenstar FS Boilers are fully modulating heat only or combi floor standing gas condensing boilers with many of the same features and customer benefits of the Greenstar wall boiler, with some additional innovations.

Installation has been simplified, with two new innovations:

  a. The Greenstar FS includes an integrated supply return manifold that can be field converted into a low loss header (LLH) to accommodate existing pipe work.

  b. All line and low voltage connections have been relocated into junction boxes on
  the back of the boiler for easier access and wiring.

Venting options have been expanded from PVC, CPVC, concentric & ridged PP to also include flexible PP venting. This provides a quick and easy venting solution for retrofit applications where the boiler and piping is not relocated.

The FW200 Weather Compensation Boiler Control (87182262150) is an optional accessory and is not included with the Greenstar Floor Standing Boilers. The New System Control (NSC), capable of controlling multiple zones, will be launched around the same time as the new Greenstar FS to provide a flexible heating combination.  Please call Global Protankless Supply at 866-289-4652 for further details and to place your order.

Calculating Combustion Air Needed for Bosch Gas Tankless Water Heaters

The amount of combustion air today is very limited due to our attempt to reduce our fuel consumption. We are replacing our windows, doors, weather-stripping, caulking and adding insulation. Years ago there were no double pane windows in the basements much less steel insulated doors in the basement leading to the outside. There were old single pane glass windows and old wooden doors which, a lot of times you could see daylight around the door frame.

Today we have added thermo pane windows in the basement, new steel doors complete with magnetic seals. We even insulate the exterior perimeter between the floor joists. All these ideas are good, but they steal much needed combustion air required for a safe combustion process needed for a gas appliance. If your heating appliance is using indoor air for combustion you must be aware of the amount of combustion air that is required.

The combustion process requires the air being burned to contain 20.9% oxygen. If it does not, the flame will start producing CO (carbon monoxide). This is an odor free gas which gets inhaled and stops the body from absorbing oxygen. CO poisoning happens every year. We must be more concerned about this when we tighten up our homes and have appliances which use indoor air for combustion.  Gas appliances should never be installed in bathrooms or bedrooms where doors are normally kept closed.  This is stated in the National Fuel Gas Code (NFGC) manual.  Please also consult local codes for further clarification.

The federal code requires 50 cu ft. of space per 1000 Btu's input from your gas heating appliance. Your state or local code may exceed that. If we know what the input of the appliance is and divide it by the total cu. Ft. of the mechanical room say where the appliance is installed the answer would have to be at least 50 cu ft. per. If we do not have 50 cu. ft. per thousand Btu's, we must bring combustion air in from the outside. If there are hallways and other rooms available due to no door being on the mechanical room we can also calculate these other areas.

We need to measure all the areas we can get combustion air from, until we come to a doorway with a door. The code states even if it is a louvered door, we still stop when we come to a door. If the utility room has a door mounted, even if it is open all the time you stop at the door. Since the formula uses Btu's as MBH (thousand btu/h) we do not use the last three (3) zero's. For example 130,000 would be just 130.

As an Example:

If we do the math it would look like this; 

Room = 32 feet long x 25 feet wide x 7 feet high 

Boiler = 130,000 Btu input and a 40,000 Btu Water Heater

Volume = Length x Width x Height 

Volume = 32' x 25' x 7' = 5600 Cubic Feet

Total BTUH Input = 130 MBH + 40 MBH = 170 MBH 

5600 Cubic Feet / 170 MBH = 32.95 Cubic Feet per 1000 BTU

Combustion Air will be Required!!

Any additional combustion air needed beyond what is already available must be taken from the outdoors.  When bringing air from the outside you only need to bring in the balance of what you need. When in direct communication with the outdoors you need 1 sq in of free space for every 4000 Btu's.

Global Pro Tankless Supply 4th of July Sale

Global Pro Tankless Supply is pleased to announce our 4th of July Sale that will be running from June 30th through July 6th 2015 at midnight ET. Everything will be marked way down for this special sale period.  Global Pro Tankless Supply will meet or beat any other authorized distributor's price as part of this promotion.  Global Pro Tankless Supply would need to verify the competitors discounted price either in e-mail or through a website.

Global Pro Tankless Supply will be knocking prices down on all our Bosch Gas tankless water heaters, electric tankless water heaters, Bosch Greenstar Boilers and Combi Boilers.  You can call us for an extra discount of $25 off for the Bosch Greentherm and Greenstar Boilers by referencing coupon code:  PRO2015.

We also have special July 4th sale pricing on our Humphrey gas lights & accessories, Danfoss electric in-floor heating mats, Z-Vent Stainless Steel Venting and Virgo water filtration systems.

Please feel free to e-mail us with questions at info@prowaterheatersupply.com  or call us at 866-289-4652. We are open 24-7 to assist you in selecting the best product for your needs.

Replacement Heat Exchangers Now on Global Protankless Supply

Global Protankless Supply is now carrying the replacement heat exchangers for all the Bosch gas tankless water heaters.  The heat exchangers are made of high quality copper. Below is a list of all the heat exchangers and their current part numbers.  Older part numbers are also listed as part numbers have changed over the years.

Bosch Therm C1210ES / C1210ESC Heat Exchanger Part 8705406419 (87054064190 or 8-705-406-419-0).  This part is also the replacement Heat Exchanger for the older Bosch ProTankless 920ES and 920ESC condensing tankless water heaters.

Bosch Greentherm C1050ES-LP / C950ES-LP (Liquid Propane) Heat Exchanger Part 8738704026 (87387040260 or 8-738-704-026-0).

Bosch Greentherm C1050ES-NG / C950ES-NG (Natural Gas) Heat Exchanger Part 8738704117 (87387041170 or 8-738-704-117-0).

Bosch Therm C1050ES-LP / C950ES-LP (Liquid Propane) Heat Exchanger Part 8705406421 (87054064210 or 8-705-406-421-0).

Bosch Therm C1050ES-NG / C950ES-NG (Natural Gas) Heat Exchanger Part 8738721270 (87387212700 or 8-738-721-270-0).

Bosch Therm 940ES / 830ES Heat Exchanger Part 8738701985 (87387019850 or 8-738-701-985-0). This part is also the replacement Heat Exchanger for the Therm 940ESO, Bosch ProTankless 715ES, Bosch AquaStar 2700ES and 2400ES and the Bosch Evolution 500.  Older part numbers were 8705406422, 87054064220, 8-705-406-422-0, 8705406356, 87054063560, 8-705-406-356-0.

Bosch ProTankless 635ES / 635ESO Heat Exchanger Part 8705406285 (87054062850 or 8-705-406-285-0).  This part is also the replacement Heat Exchanger for the Bosch AquaStar 2400E, 2400EO, 250SX and 250SXO tankless water heaters.

Bosch Therm 520 Heat Exchanger Part 8705406386 (87054063860 or 8-705-406-386-0).  The Bosch Therm 520 Heat Exchanger Part 8705406386 is the replacement heat exchanger for all Bosch Therm 520PN and 520HN tankless water heaters and for all Bosch ProTankless 425PN and certain Bosch ProTankless 425HN (with serial numbers starting 686 and higher) tankless water heaters. It is also the replacement heat exchanger for all Bosch AquaStar 1600P and 1600H tankless water heaters. This heat exchanger replaces the obsolete 8705406275 (87054062750, 8-705-406-275-0) heat exchanger.

Bosch ProTankless 425 Heat Exchanger Part 8705406380 (87054063800 or 8-705-406-380-0).  The Bosch 425 Heat Exchanger is the replacement heat exchanger for the following Bosch ProTankless water heaters: 425EF, 425HN (with serial numbers starting 685 and lower) and 425HNO and the following Bosch AquaStar tankless water heaters: 125B, 125BO, 125BL, 125X, 125HX, 125FX.  This heat exchanger will also work with the following Bosch WR400 series tankless water heaters: WR400-1KV1P23S3100, W400KD5 P23S3100T2, WR400-3K V1B23S3100, WR400-7K V1G23S3195, WR430-3K VM1E23S3190 and WR430-3K VM1E23S3195.  Older part numbers were 8705406235, 87054062350, 8-705-406-235-0.

Bosch Universal Hydro Generator

The Bosch universal Hydro Generator, part number 8707406104 (87074061040 or 8-707-406-104-0) is designed to work with all newer Bosch Therm 520HN heaters as well as all older model hydro generated units.  The universal hydrogenerator comes with miscellaneous water pipes, gaskets and bushings to adapt to the older units. The hydro generator works with water flow and has a small wheel that spins when the water starts to flow. The small wheel inside has a magnet on it that when spinning produces a certain amount of mili volts that is transferred through a couple wires to the ignition unit and that in turn lets the ignition unit light the pilot and then the main burner.  There is no need for any electrical power to operate the heater.

The older units that would require the universal hydro generator are the Bosch model 125HX, 425HN, 425HNO, 1600H and the Bosch WR400 series heater WR400-7K V1G23S3195.  The new universal Hydro Generator part replaces all older hydrogenerators such as 8707406043 (87074060430 or 8-707-406-043-0), 8707426026 (87074260260 or 8-707-426-026-0), 8707406059 (87074060590 or 8-707-406-059-0), 8707406069 (87074060690 or 8-707-406-069-0), 8707406095 (87074060950 or 8-707-406-095-0) and 8707406071 (87074060710 or 8-707-406-071-0).

PCB Control Boards for Powerstream Pro & Bosch Tronic 5000 Electric Tankless

The PCB control board (Printed Circuit Board) is a thermostatically controlled circuit board that allows the whole house electric tankless water heater, models WH17, WH27 & WH36, to be manually controlled by a temperature dial that would range in temperature from 86-131 degrees. The PCB in conjunction with a flow transducer enables the PCB to turn on additional elements in the heater as necessary depending on the amount of gallons per minute (gpm) flowing through the heater.

The PCB would recognize many factors in the function of the heater to maintain a steady temperature and all of this is determined on where the temperature knob is set to, the gpm flowing through the heater, and the temperature of the incoming ground water.

To obtain the maximum heating potential of the Bosch Tronic 5000 electric tankless water heater it must be wired correctly and have the full required voltage to the unit. The Bosch Tronic 5000 WH17 would require 2 independent double pole 40 amp breakers wired with 8 gauge wire and could draw a maximum of 80 amps at full flow through the heater. The WH17 would require the home to be supplied with a minimum of a 150 amp service. The Bosch Tronic 5000 WH27 would require 3 independent double pole 40 amp breakers wired with 8 gauge wire and could draw a maximum of 120 amps at full flow through the heater. The WH27 would require the home to be supplied with a minimum of a 200 amp service.  The Bosch Tronic 5000 WH36 would require 3 independent double pole 60 amp breakers wired with 6 gauge wire and could draw a maximum of 180 amps at full flow through the heater. The WH36 would require the home to be supplied with a minimum of a 300 amp service.

The maximum inlet water temperature allowed into the electric tankless is 86 degrees Fahrenheit.

The Bosch Tronic 5000 WH17, WH27 & WH36 have had many upgrades and engineering improvements over the years. In January 2007 the WH17(RP17PT) & WH27(RP27PT) went from having copper canisters that contain the heating elements to an upgraded Polymer module. The PCB control board was also upgraded to maintain a more steady temperature that works with the heating elements in the polymer modules.

Below are the designated PCB control board part numbers for the units before and after 2007.

Before 2007 with serial #60A 00000 or lower:
Powerstream Pro RP17PT PCB with copper can units, part #93-793777
Powerstream Pro RP27PT PCB with copper can units, part #93-793778

After 2007 with serial number between #60A 80000 - 107:
Powerstream Pro RP17PT PCB with polymer units, part #93-793843
Powerstream Pro RP27PT PCB with polymer units, part #93-793844

Newest Bosch Tronic 5000 units with serial number after 108:
Bosch Tronic 5000 WH17 PCB with polymer units, part #8738701732
Bosch Tronic 5000 WH27 PCB with polymer units, part #8738701738

Bosch Tronic 5000 WH36 PCB with polymer units, part #8738701744

Bosch Tankless Water Heaters with New Built-In External Water Filters

Bosch Thermotechnology is always improving the gas-fired tankless water heaters and has recently improved all the sealed combustion tankless water heaters and have added a new hydraulic block on the bottom of all the units that incorporates a new built in external water filter.

The Bosch Greentherm C950ES and Bosch Greentherm C1050ES condensing heaters were designed with the new hydraulic block and external water filter built in.  The Bosch Therm C1210ES/ESC, Bosch 940ES and the Bosch 830ES have recently had the new hydraulic block and external water filter added.  After Serial number beginning with "301" will have the built in external water filter.

Built-in External Water Filter

All of the older Bosch "Therm" models before serial number 301 had the external water filter, part #8703035356 and was sold as an accessory.

Please contact Global Protankless Supply with any questions at 866-289-4652.

Backdraft Reducer #9301BFP for Bosch Tankless Water Heaters

The Heat Fab backdraft reducer (9301BFP) is the preferred option for limiting backdraft for the Bosch Condensing tankless water heaters (see fig. 22).

Note: The following solution is available only for 3" diameter venting.

In cold climates, components of a tankless water heater can freeze and burst from negative draft. A leading cause of negative draft is combustion appliances in the building not being supplied with sufficient combustion air. A wood stove or furnace can pull its combustion air from the water heater‘s vent pipe, allowing the cold incoming air to freeze the cold water in the heat exchanger. The best prevention for this risk is two pipe venting which draws the appliance combustion air from outside creating a positive pressure inside the unit.

For this solution to be effective, the internal flapper must be 100% closed when the water heater is not running. Refer to Figures 24 and 25 for preferred installation positions in the vent system.

Installation considerations:
• Install damper per the supplied manufacturer‘s instructions.
• The damper is only to be used in the exhaust vent piping.
• Ensure directional arrow on damper label faces in the same direction as exhaust flow.
• If installed horizontally, the axis must be horizontal or slightly pitched up towards termination to ensure damper closes 100% when heater is not running.
• To allow accessibility, damper must not be installed in an enclosed section of vent pipe.
• Do not install damper in unconditioned spaces (e.g. attics) Condensation can build up while the heater is running which can later freeze and potentially block the flapper.

The Bosch C1210ES/ESC, C1050ES & C950ES are all approved to use the Backdraft Reducer. 

Phasing out of Bosch Therm 940ESO Outdoor Unit

Bosch is phasing out the Therm 940ESO model tankless water heater in Natural Gas, Part Number 7738000001 and Liquid Propane, Part Number 7738000002.

Bosch will continue to still make the Bosch Therm 940ES NG & LP tankless water heaters. The Bosch Therm Outdoor Kit (BTOK) will be sold as an accessory for outdoor installations.

The Phase out of the Bosch Therm 940ESO outdoor unit will be immediate. Please see the list below for model numbers, color changes by manufacturing date and BTOK model numbers.

Bosch Therm 940ES NG - #7703311076
Bosch Therm 940ES LP - #7703411073
(Gray Models, FD prior to FD420 - White Models, on or after FD420)

BTOK Outdoor Kit - Gray #7709003913
BTOK Outdoor Kit - White #7736502448

Please call Global Protankless Supply at 866-289-4652 for further questions or ordering.

Bosch Greenstar Intelligent Cascade Module (ICM) #7719003528

Bosch is always working on new ways to improve their products and has recently came out with an Intelligent Cascading Module (ICM) part #7719003528 for the Bosch Greenstar gas-fired wall-hung boilers.  The ICM modules are designed to control cascade systems.  A cascade system is a heating system where several smaller boilers are connected in parallel to achieve higher output.  The Bosch ICM modules are only suitable for controlling Bosch Greenstar boilers with BUS-enabled Heatronic 3 systems.

One Bosch ICM module can control up to 4 Greenstar boilers.  By conecting up to 4 ICM modules, up to 16 boilers can be linked to form a single cascade.  Depending on the heating system controls used, a cascade system with up to 4 or up to 16 boilers can be created.  The maximum number of boilers that can be connected and the number of ICM modules required for the different systems are shown in the table below.

Bosch Tankless Water Heaters and Pressure Regulating Valves

1. A Pressure Regulating Valve is a valve that automatically cuts off the flow of a liquid or gas at a certain pressure. Regulators are used to allow high-pressure fluid supply lines or tanks to be reduced to safe and/or usable pressures for various applications.
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3. Bosch tankless water heaters work on water pressure and flow.  Some people experience fluctuating temperatures sometimes if they are on a well system as the well pump has a high and low setting for when the pump comes on and off.  Most common well pumps are set to like 30 - 55 psi of pressure.  So when you are using the hot water and if the pump kicks on during this time you could see a change in flow and pressure which will change the flow and water temperature out of the Bosch tankless water heater.  
4. A Pressure Regulating Valve installed on the cold water line before the Bosch tankless water heater can be set at the low PSI such as 30 psi and then will always maintain that 30 psi consistently whether the pump kicks on or not.
5. There are all sorts of different pressure regulating and pressure reducing valves on the market.  
6.