Showing posts with label PCB. Show all posts
Showing posts with label PCB. Show all posts

Monday, December 2, 2013

New Bosch Powerstar AE-115 & AE-125 Electric Tankless

Bosch Powerstar AE-115 & AE-125 Electric Tankless Water Heaters

Ideal for replacing your electric storage tank water heater. The Bosch Powerstar AE-115 & AE-125 electric whole house tankless water heaters are compact and powerful and can be installed virtually anywhere inside the home. Advantages include endless hot water, reduced electricity costs and substantial space savings.

Designed to replace a 20 - 40 gallon electric tank. The Bosch Powerstar AE-115 & Bosch Powerstar AE-125 electric tankless water heaters are built to last. Each heater module is protected by an electro-mechanical thermal cut-out. If the temperature of any of the heater modules gets too high (over 195 degrees), then the cut-out will trip and cut the power to that heater module. If the cut-out trips, it must be reset while the circuit breakers are off. If you are not comfortable or qualified to perform this task, consult the original installer or a licensed electrician. This cut-out will only trip in exceptional circumstances. They have Plastic Polymer Modules and brass fittings. These small electric tankless water heaters can be installed virtually anywhere in the home and, of course, produce an endless supply of hot water.

There are many changes in the new Powerstar AE-115 and the AE-125 compared to the older models Powerstar AE-115 & AE-125.

The improvements for the New Bosch Powerstar AE-115 & AE-125 are:
  • The units overall height is shortened by 3 inches due to reconstruction and placement of the main PCB board in the bottom of the unit.  (AE115 PCB Board #8-738-701-732 (87387017320), AE125 PCB Board #8-738-701-738 (87387017380).  These PCB boards are required for all new Powerstar units with serial number beginning with 108 and higher.
  • The Heating element assembly modules inside the unit have been redesigned to change the flow of the water in the modules to a different angle so as to not allow the mineral deposits to build up on the elements.
  • There has been new single triac and dual triac PCB boards attached to the top of the heating modules as to give the heater more sensibility and maintain a more consistant heat.  (Single Triac PCB #8-738-701-733, Dual Triac PCB #8-738-701-723).
  • The Thermal Cutouts on the top of the heating modules have been redesigned to trip at a little lower temperature of 195 degrees F to keep the elements from being damaged and overheating and hurting the piping and modules.

The minimum activation rate required for the unit to activate. (Activation rates: AE-115 = 0.6 GPM, AE-125 = 0.8 GPM).

The AE115 & AE125 are designed for cold potable water only. These water heaters are not designed for preheated water or recirculation applications. Increase flow rate where ever possible if water is coming out too hot.

Verify incoming water supply is at least 30psi. For people on well systems, the recommended pressure range is 30-50psi.




Maximum flow rates for each unit are as follows. AE-115 = 2.3gpm, AE-125 = 3.5gpm.


Friday, November 26, 2010

PCB Control Boards for Powerstar AE-115 & AE-125

The PCB control board (Printed Circuit Board) is a thermostatically controlled circuit board that allows the electric tankless water heater, model AE115 & AE125 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 too, the gpm flowing through the heater and the temperature of the incoming ground water.

To obtain the maximum heating potential of the Powerstar electric tankless water heater, it must be wired correctly and have the full required voltage to the unit. The Powerstar AE115 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 Powerstar AE115 would require the home to be supplied with a minimum of a 150 amp service. The Powerstar AE125 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 Powerstar AE125 would require the home to be supplied with a minimum of a 200 amp service.

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

The Powerstar AE-115 & AE-125 have had many upgrades and engineering improvements over the years. In January 2007 the AE-115 & AE-125 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:
Powerstar AE-115 PCB with copper can units, part #93-793777
Powerstar AE-125 PCB with copper can units, part #93-793778

After 2007 with serial #60A 80000 or higher:
Powerstar AE-115 PCB with polymer units, part #93-793843
Powerstar AE-125 PCB with polymer units, part #93-793844