Installation Instructions

Installation Manual
Page
5
• This manual provides information necessary for the installation,operation, and maintenance of the
micro-boiler.
• The model description is listed on the rating plate which is attached to the side panel of the micro-
boiler.
• Please read all installation instructions completely before installing this product.
• If you have any problems or questions regarding this equipment, consult the manufacturer or its
local representative.
• These hight efciency models have a built-in secondary heat exchanger that absorbs latent heat
from the exhaust gas.
• The Hydro Smart HS120 Condensing Gas Micro Boiler is only to be installed indoors.
• The principle behind condensing micro-boiler is simple:
INTRODUCTION
1. Your thermostat indicates a need for heat and turns on a circulator pump.
2. Fluid enters the heater.
3. The ow sensor detects the uid ow.
4. The computer initiates the fan motor and sends a signal to the igniter to create an ignition spark.
5. The gas ignites and ames appear within the burner chamber.
6. Fluid circulates through the heat exchanger and then gets hot.
7. Using thermistors to measure temperatures throughout the micro-boiler, the computer modulates
the gas and water valves to ensure proper output uid temperature.
8. Your room reaches desired temperature and the micro-boiler shuts off.
* This diagram illustrates condensing micro-boiler design concepts only and does not accurately
represent the micro-boiler's physical description.
Introduction
Burners
Exhaust
Secondary
heat exchanger
Primary
heat exchanger
Igniter
Gas valve
Fan motor
Flow sensor
Condensate
drain port
Gas inlet
Cold water inlet
Thermistor
Hot water outlet
Thermistor
Intake port
Exhaust
Thermistor
Water control
valve
Computer
board