Monday, July 27, 2015

Turn Down Ratios for Bosch Greenstar Staight & 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 combination boilers:

Bosch Greenstar 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 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 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 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 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 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 regular boilers:

Bosch Greenstar 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 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 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 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 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 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 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 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 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 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

Wednesday, July 15, 2015

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.

FW200 will be available as an optional accessory and will not be included in the contents of delivery. 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.

Wednesday, July 1, 2015

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  or call us at 866-289-4652. We are open 24-7 to assist you in selecting the best product for your needs.

Monday, June 15, 2015

Replacement Heat Exchangers Now on Global Protankless Supply

Global Protankless Supply is now carrying all the replacement heat exchangers for all the Bosch wholesale model 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 the Bosch ProTankless 425HN (with serial numbers starting 686 and higher) It is also the replacement heat exchanger for the Bosch AquaStar 1600P and 1600H tankless water heaters.

Bosch ProTankless 425PN Heat Exchanger Part 8705406275 (87054062750 or 8-705-406-275-0).

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.

Wednesday, June 3, 2015

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).

Thursday, May 14, 2015

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