Bosch Therm 520HN NG & LP Tankless Water Heater

The new Bosch Therm 520HN comes set for either NG (Natural Gas) or LP (Liquid Propane).  The 520HN has a hydro ignition and is a naturally drafting heater and requires no power to operate.  This unit is basically for 1 major application at a time such as 1 shower at a time.  The Bosch 520 HN Needs to be vented vertically with a 5" B-vent up through the roof for a minimum of 6' to the raincap.  If the heater has to be vented out the sidewall then you must use the AQ4 Powervent kit and this kit would require 110V power.  The gas connection at the bottom of the heater is a standard 3/4" connection.

The new Bosch Therm 520HN is a direct replacement for many of the older model heaters.  Below is a list of the units that the 520HN would replace.  Please keep in mind to always be aware of gas line sizing and the length of the gas line run.

The Bosch Therm 520HN could replace:

Bosch 1600P or 1600H: (If either one of these units was vented horizontally out the sidewall with the AQ4 powervent kit then that same AQ4 powervent kit can be used for the new Bosch Therm 520HN)

Bosch Aquastar 125B, 125X, 125HX, 425PN or the 425HN: (If any of these units was vented horizontally out the sidewall with the AQ1 powervent kit then that AQ1 powervent kit WILL NOT work for the new Bosch Therm 520HN.  You would need to install the new AQ4 powervent kit for the new Bosch Therm 520HN)

ELM Le Blanc 170VP or 125VP:  (If either one of these units was vented horizontally out the sidewall with the AQ1 powervent kit then that AQ1 powervent kit WILL NOT work for the new Bosch Therm 520HN.  You would need to install the new AQ4 powervent kit for the new Bosch Therm 520HN)

The Bosch Therm 520HN is a direct replacement for the older tankless water heaters listed above but you still always want to make sure and refer to the installation manual and follow the gas line sizing chart and venting requirements.  Please also refer to local code for all other restrictions and approvals.

Bosch Therm 520PN NG & LP Tankless Water Heater

The new Bosch Therm 520PN comes set for either NG (Natural Gas) or LP (Liquid Propane).  The 520PN has a standing pilot and is a naturally drafting heater and requires no power to operate.  This unit is basically for 1 major application at a time such as 1 shower at a time.  The Bosch 520 PN Needs to be vented vertically with a 5" B-vent up through the roof for a minimum of 6' to the raincap.  If the heater has to be vented out the sidewall then you must use the AQ4 Powervent kit and this kit would require 110V power.  The gas connection at the bottom of the heater is a standard 3/4" connection.

The new Bosch Therm 520PN is a direct replacement for many of the older model heaters.  Below is a list of the units that the 520PN would replace.  Please keep in mind to always be aware of gas line sizing and the length of the gas line run.

The Bosch Therm 520PN could replace:

Bosch 1600P or 1600H: (If either one of these units was vented horizontally out the sidewall with the AQ4 powervent kit then that same AQ4 powervent kit can be used for the new Bosch Therm 520PN)

Bosch Aquastar 125B, 125X, 125HX, 425PN or the 425HN: (If any of these units was vented horizontally out the sidewall with the AQ1 powervent kit then that AQ1 powervent kit WILL NOT work for the new Bosch Therm 520PN.  You would need to install the new AQ4 powervent kit for the new Bosch Therm 520PN)

ELM Le Blanc 170VP or 125VP:  (If either one of these units was vented horizontally out the sidewall with the AQ1 powervent kit then that AQ1 powervent kit WILL NOT work for the new Bosch Therm 520PN.  You would need to install the new AQ4 powervent kit for the new Bosch Therm 520PN)

The Bosch Therm 520PN is a direct replacement for the older tankless water heaters listed above but you still always want to make sure and refer to the installation manual and follow the gas line sizing chart and venting requirements.  Please also refer to local code for all other restrictions and approvals.

New Greentherm PP Concentric up and out vent kit

New for the Bosch Greentherm C 950 ES & C 1050 ES is the polypropylene concentric up-and-out venting kit consisting of the appliance adapter, a 90° elbow, and a termination. This is the simplest and quickest venting option possible for a condensing tankless unit. The outer metal pipe and the inner polypropylene pipe make it both lightweight and rigid. The termination is telescopic to allow for varying wall thicknesses.

This new PP concentric up and out vent kit is approved for the New Green Therm C950ES & C1050ES tankless water heaters.  The PP concentric up and out vent kit is also approved for the Bosch Therm C950ES & C1050ES.  

Before attaching the appliance adapter to the top of the heater, a second metal plate comes with the kit and would cover the other intake air hole.  Then you would want to remove the exhaust collar from the top middle of the heater and then attach the appliance adapter as this will enable the heater to exhaust to the outside and also take its combustion air down the outer side of the same hole.

Bosch Greentherm PP concentric up and out vent kit (7738003210)

The Greentherm models C 950 ES & C1050ES are also approved for PP twin-pipe venting systems. Availability of generic PP vent pipe has increased and systems are becoming more popular due to ease of installation.  The twin pipe installation would be used if the customer needed to go out a different area out the sidewall or through the roof and would need to take the combustion air from the outside also.



PP Common Venting Systems for Cascaded Units

New for the Greentherm C 950 ES and C 1050 ES, and the Therm C 1210 ES and C 1210 ESC, is a common venting system of polypropylene pipe for up to four appliances. Offered in either a side by side or back to back configuration, the kits allow for a single vent pipe for all units. Combustion air must be taken from the room for multiple units common vented.  A 3" PVC 90 degree elbow would want to be placed on either the left or right air intake hole for the combustion air to keep anything from falling into the heater.  This is mandatory for commercial applications, with multiple units installed and that the multiple units are common vented with either the side by side or back to back venting option.  All other applications such as residential, single units, etc. must take the combustion air from the outside using 3" PVC or 3" dia PP pipe.  Please refer to the installation manual for the Bosch tankless water heater for the combustion air requirements for the heater. 

Side by side with horizontal termination (left),

back to back with vertical termination (right)



The new polypropylene pipe (PP) common venting system features different kits for cascaded units of 2, 3 or 4 units.  Kits would have to be ordered as needed:

Kit A - side by side, units #1 & #2 (2 heaters) (7736501100)

Kit B - side by side, units #3 & #4 (1 heater) (7736501254)

Kit C - back to back, units #1 & #2 (2 heaters) (7736501253)

Kit D - Extension back to back, units #3 & #4 (2 heaters) (7736501252)

There are also additional 6" diameter PP venting pieces available.  There are additional:

Horizontal Termination Dia 6"  (7736501117)

Vertical Termination Dia 6"  (7736501119)

Extension rigid straight pipe 20" Dia 6"  (7736501137)

Extension rigid straight pipe 40" Dia 6"  (7736501135)

Extension rigid straight pipe 80" Dia 6"  (7736501133)

Rigid 90 degree elbow Dia 6"  (7736501132)

For example:

Say you were common venting and cascading 4 units side by side and venting up through the roof then you would want 1 - Kit A for units #1 & #2, 1 - Kit B for unit #3 and then 1 - Kit B for unit #4.  You would also then need 1 - 90 degree elbow, how many extra feet of extension straight pipe and then the vertical termination.

New Bosch Greentherm C 1050 ES Condensing Tankless Water Heater

The New Bosch Greentherm C 1050 ES Condensing tankless water heater is a top performance, fully condensing gas tankless water heater from Bosch. This 199,000 BTU heater is designed for residential or commercial applications and can deliver hot water up to 140 degrees F with a 10.5 GPM flow rate.  Not approved for space heating applications.

This Energy Star approved tankless water heater can produce enough hot water for 2-3 major applications in most homes or is good for most commercial applications.  The Greentherm C 1050 ES is now 94% energy efficient.

Unlike traditional non-condensing models, condensing technology captures heat from the exhaust gas and uses it to preheat the incoming cold water. This increases efficiency and reduces emissions -- well ahead of the 2012 Low NOX emissions standards set by SCAQMD (California -- South Coast Air Quality Management District).  The Greentherm C1050ES now has NSF Certification (National Sanitation Foundation) for commercial kitchens.  The Bosch Green Therm C1050ES now has an added bypass tube connecting the cold and hot water lines inside the unit so the heater can mix a little cold water with the hot to alleviate and fluctuations and maintain a more stable temperature.  Standard now also are three NTC temperature sensors. With a new sensor immediately after the HEX, the Greentherm achieves benchmark temperature control. The NTCs are no longer clipped on, but rather installed into the inlet and outlet pipes.

The Bosch Greentherm C 1050 ES features an electronic ignition system and can vent through either 3 inch or 4 inch diameter PVC vent pipe either through the side wall or up through the roof.  The Greentherm C950ES now takes a new concentric venting system and attaches right to the top of the heater and takes its intake air and exhaust out through one hole to the outside.  The Greentherm C1050ES can now be cascaded together with up to 4 units and they can all vent into one pipe using a special venting kit to the outside.  Installation can be done venting up to 4 units together into the one pipe having the heaters mounted side by side or back to back.  The combustion air for the units will need to be taken from the inside of the building.

The Bosch Greentherm C 1050 ES comes with built in freeze protection.  The Greentherm C1050ES also comes with an external water filter screen.  The Bosch Green Therm C1050ES does not come with a 3/4" pressure relief valve, this is an accessory that would have to be ordered separately.

The freeze prevention kit is designed to provide protection for the water heater down to approximately 5°F for short term conditions only. It will not protect the appliance in areas where the temperature is routinely expected to be below freezing.  The freeze prevention kit will not protect plumbing outside the appliance from freezing.

The Bosch Greentherm C 1050 ES comes with a limited 15 year warranty on the heat exchanger and 5 years on all other parts.  Service and labor costs are not covered.

New Bosch Greentherm C 950 ES Condensing Tankless Water Heater

The New Bosch Greentherm C 950 ES Condensing tankless water heater is a top performance, fully condensing gas tankless water heater from Bosch. This 175,000 BTU heater is designed for residential or commercial applications and can deliver hot water up to 140 degrees F with a 9.2 GPM flow rate.  Not approved for space heating applications.

This Energy Star approved tankless water heater can produce enough hot water for 2 major applications in most homes.  The Greentherm C 950 ES is now 93% energy efficient.

Unlike traditional non-condensing models, condensing technology captures heat from the exhaust gas and uses it to preheat the incoming cold water. This increases efficiency and reduces emissions -- well ahead of the 2012 Low NOX emissions standards set by SCAQMD (California -- South Coast Air Quality Management District).  The Greentherm C950ES now has NSF Certification (National Sanitation Foundation) for commercial kitchens.  The Bosch Green Therm C950ES now has an added bypass tube connecting the cold and hot water lines inside the unit so the heater can mix a little cold water with the hot to alleviate and fluctuations and maintan a more stable temperature.  Standard now also are three NTC temperature sensors. With a new sensor immediately after the HEX, the Greentherm achieves benchmark temperature control. The NTCs are no longer clipped on, but rather installed into the inlet and outlet pipes.

The Bosch Greentherm C 950 ES features an electronic ignition system and can vent through either 3 inch or 4 inch diameter PVC vent pipe either through the side wall or up through the roof.  The Greentherm C950ES now takes a new concentric venting system and attaches right to the top of the heater and takes its intake air and exhaust out through one hole to the outside.  The Greentherm C950ES can now be cascaded together with up to 4 units and they can all vent into one pipe using a special venting kit to the outside.  Installation can be done venting up to 4 units together into the one pipe having the heaters mounted side by side or back to back.  The combustion air for the units will need to be taken from the inside of the building.

The Bosch Greentherm C 950 ES comes with builtin freeze protection.  The Greentherm 950ES also comes with an external water filter screen.  The Bosch Greentherm C950ES does not come with a 3/4" pressure relief valve, this is an accessory that would have to be ordered seperately.

The freeze prevention kit is designed to provide protection for the water heater down to approximately 5°F for short term conditions only. It will not protect the appliance in areas where the temperature is routinely expected to be below freezing.  The freeze prevention kit will not protect plumbing outside the appliance from freezing.

The Bosch Greentherm C 950 ES comes with a limited 15 year warranty on the heat exchanger and 5 years on all other parts.  Service and labor costs are not covered.

New Bosch Tronic 3000T ES Mini-Tank Water Heaters

Bosch has rebranded the Ariston Pro Ti line of electric mini-tank water heaters. They are now labeled as Bosch Tronic 3000T ES Electric Mini-tank Water Heaters.

The old Ariston Pro Ti models GL2.5Ti & GL2.5TiS are now the Bosch ES 2.5.
The old Ariston Pro Ti models GL4Ti & GL4TiS are now the Bosch ES 4 .
The old Ariston Pro Ti models GL8Ti & GL8TiS are now the Bosch ES 8.

The new Bosch ES2.5, ES4 and ES8 electric mini-tank water heaters are the same size as the mini-tanks that each replaces.  The replacement parts for the new Bosch ES2.5, ES4 and ES8 are different now and will not work for the older Ariston GL2.5Ti, GL4Ti or the GL8Ti.

*  Please note that the new Bosch ES4 is not a direct replacement for the retail model Ariston GL4 as the Bosch ES4 is 13 1/2" in depth and the retail Ariston GL4 is 12 1/4" deep.

The new Bosch ES2.5, ES4 and ES8 have many new improvements since they have been upgraded. The mini tanks have a new temperature adjustment knob on the front of the unit to raise and lower the temperature from 65 Deg F to 145 Deg F. On the older models you would have to remove the grey oval cover to access the temperature control knob.

The Bosch ES2.5, ES4 and ES8 models have a new improved thermostat that features a new sensing probe that is attached to the thermostat and inserts into the cavity of the new heating element so the heater can adjust temperatures quicker and maintain a more consistent heat.

The new model ES8 now has to be hard wired to a plug for 110V.  Global Protankless Supply carries 6' cords for the Bosch ES8 heater.

See our web site at www.prowaterheatersupply.com for all the details.

Steve