MODEL 250SXO - OUTDOOR MODEL For exterior use only Electronic Ignition and built in Freeze protection Suitable for heating potable water only Not approved for space heating purposes 250 SXO NG - Natural Gas 250 SXO LP - Liquefied Petroleum (LP) Gas 6 720 607 440 US (05.03) JS Warning: If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or death.
Index Index 1 Warning 2 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.9.1 2.9.2 2.9.3 2.10 2.11 2.12 2.13 4 4 4 6 7 7 8 8 10 12 12 12 12 13 14 14 2.
Warning What to do if you smell gas • Close gas valve. • Do not try to light any appliance. • Do not touch any electrical switch; do not use any phone in your building. • Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions. • If you cannot reach your gas supplier, call the fire department. • Installation and service must be performed by a qualified installer, service agency or the gas supplier.
Appliance details 2 Appliance details 2.1 Features Maximum input 175,000 Btu/h (51.2 kW) Parts • Touch Pad interface control Efficiency in % • High power pre-mix compact burner with low NOx emissions Recovery efficiency 86.5% • Modulating Gas Valve with constant gas: air ratio control Min. Output 31,131 Btu/h (9,1 kW) • Modulating water valve for improved comfort and temperature control Temperature Control • Freeze protection.
Appliance details Combustion UNPACKING THE 250 SXO HEATER • NOx ≤ 55 ppm This heater is packed securely. • CO ≤ 250 ppm. The box includes: Dimensions • Depth (in): 8 ½” (220 mm) • Width (in): 15 ¾” (400 mm) • Height (in): 26” (650 mm) • Weight: 47 pounds (21 kg). Gas types Natural Gas. LP Gas. CO2 analyzer is required to convert from one gas type to another. Please contact CEC for specific instructions.
Appliance details 2.3 Fig. 3 1 2 3 4 5 6 Dimensions and Minimum installation clearances Dimensions Cover On/Off switch Reset button LCD display Program button Temperature buttons Fig. 4 Minimum clearances Model 250 SXO TOP (A) 3 ft. FRONT (B) 4 ft. BACK 0” SIDES 4 ft. BOTTOM (C) 1 ft.
Appliance details 2.4 General rules to follow for safe operation B 1. You should follow these instructions when you install your heater. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada: The Installation should conform with CGA B149.(1,2) INSTALLATION CODES and /or local installation codes. B 2. Carefully plan where you install the heater. Proper clearances must be followed. B 3.
Appliance details 2.6 Heater Placement and Clearances 2.7 The 250 SXO is design certified for installation directly on a combustible wall. (see 2.7 Mounting installation) For installation on vinyl siding see Fig. 10. Keep the area below the heater free of combustible material. Minimum clearances If the appliance is installed under an overhang, there must be a 36” clearance from the top of the appliance and the mounting area must be open in front and on the sides of the appliance.
Appliance details B After inspection, replace front cover and tighten screws, then replace plastic decal shields. B Fix the top vent cap on the top of the heater, as shown in Fig. 8). Make sure the vent cap is well fitted by taking special care that the front cover stays inside the extended corners of the vent cap, as shown in Fig. 8). The sides of the cover must be pressed with your hands to ensure it fits inside those corners. Secure it in place with its two screws. Fig.
Appliance details 2.8 Gas piping & connections Before connecting the gas supply, check the rating plate on the right side of the heater to be sure that the heater is rated for the same gas to which it will be connected. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada: The Installation should conform with CGA B149 INSTALLATION CODES and/or local installation codes.
Appliance details FOR NATURAL GAS Maximum Capacity of pipe in Cubic Feet of Gas per Hour for Gas Pressure of 0.5 Psig or less and a Pressure drop of 0.3 in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands. Follow boxed numbers for piping just one 250 SXO (example: ¾” B.I. Natural Gas pipe for 20 ft (6.1m). will handle 190,000 btu’s (55.7 kWh). For multiple appliances combine the total btu input load and then refer to applicable chart below.
Appliance details 2.9 Measuring gas pressure 2.9.1 Connecting Manometer B Shut off gas. B Remove front cover and locate inlet gas pressure measuring point (see Fig. 14). B Loosen screw inside test point fitting (do not remove) and connect manometer tube on test point. 2.9.2 Static Pressure Test Static Gas Pressure Reading (see Chapter 2.9) enter here: ___________________ Operating Gas Pressure Reading (see Chapter 2.
Appliance details 2.10 Water connections When facing the heater, the ¾” cold water inlet is on the bottom right and the hot water outlet is on the bottom left. Install the heater where it’s centrally close to hot water use points if possible, and make hot water piping runs as short as possible. INLET FILTER SCREEN lowest pressure range setting recommended is 30-50 psi (2.07 and 3.45bar).
Appliance details 2.11 Electrical connections Warning: The heater is equipped with freeze prevention equipment that will operate and prevent freezing of the water in the heater to 5°F with no wind chill. Electrical power must be maintained to the heater to allow this to function. WARNING: Proper insulation of the water lines below the heater is required if below freezing temperatures, below 32°F, are ever anticipated.
Appliance details 2.13 For your safety read before operating your water heater Warning: If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or loss of life. A. This appliance is equipped with electronic ignition for lighting the main burners. When turning the heater on, follow these instructions exactly. B. Before operating the unit, turn the On/Off switch to the right position.
Operation instructions 3 Operation instructions Fig. 19 1 2 3 4 5 6 On/Off switch Reset button Program button Increasing temperature button Decreasing temperature button LCD display 3.1 B Press buttons and requested temperature. in order to reach Power On B To start the appliance switch the button to the ON position (turn to the right position). LCD display the default temperature - temperature factory setting 122°F (50°C). Fig.
Operation instructions Setting the water temperature The desired temperature of the hot water can be adjusted on the front control panel of the heater. The 250 SXO has an electronically controlled gas valve that modulates the burner input in response to both varying hot water flow rates and/or changes in any incoming and outgoing water temperatures. Hot Water Flow and Temperature with Various Inlet Temperature (gpm/Fahrenheit) 7.00 Hot Water Flow (GPM) 6.00 5.00 4.00 3.00 2.00 1.00 0.
Operation instructions 3.3 Use of remote control accessory Fig. 26 Reset button If the problem persists, contact your installer. 3.6 Fig. 23 Remote control The wireless remote control accessory and the temperature selector buttons on the front of the water heater operate identically. Contact your distributor or CEC to order if the remote control accessory is preferred. Modification of the water heaters interior control unit (Fig.
Maintenance and service 4 Maintenance and service Warning: Always turn off the electrical power supply, turn off the manual gas valve and turn off the manual water control valves whenever servicing. The unit should be checked once a year by a gas technician. If repairs are needed, the repairs should be done by a gas technician To remove front cover B See instructions to remove front cover on page 8. Systems and parts that should be checked at least once a year Reference diagrams on pages 24 and 25.
Troubleshooting Test by following 4th bullet under BURNERS DO NOT IGNITE WHEN HOT WATER IS TURNED ON. LOW WATER FLOW/PRESSURE • Too many hot water applications are being used simultaneously or too much flow is being demanded The 250 SXO will effectively support two 2.0-2.5 gpm shower heads simultaneously or multiple sink applications. Greater draws will result in increased pressure drop and reduced flow at taps. See flow/ temperature chart on page 17.
Troubleshooting Display Cause Solution E9 Temperature limiter opened circuit (overheat). Trips at 220F (104C). Check connections. * Check heat exchanger condition.* EA No ionization during safety time (safety time out). Note: appliance makes 3 ignition attempts before entering error mode “EA”. EC The ionization signal momentarily disappeared more then 5 times in less then 30 seconds. CO2 may be out of adjustment Check gas pressure. (see chapter 2.
Electrical diagram 6 Electrical diagram Fig. 29 Electrical scheme 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Intlet water temperature sensor Ionization sensor Water flow sensor Over heat protection Temperature limiter Gas valve Fan Water valve AC Plug Ignition electrode Display PCB ON/OFF switch Fuse T 2,5A Fuse T 3,15A Terminal block Ground post Outlet water temperature sensor Connector for Anti-freeze Anti-freeze device (Heating resistors) Temperature sensor Fig.
250 SXO Functional scheme 7 250 SXO Functional scheme Fig.
Interior components diagram and parts list 8 Interior components diagram and parts list 8.1 Interior components Fig. 32 Components 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Cover On/Off switch Reset button LCD display Program button Temperature buttons Flue gas collector Mixer Heat exchanger Observation window Inlet air duct Control unit Exhaust fan Water valve Gas valve Fig.
Interior components diagram and parts list 8.2 Components diagram Fig.
Interior components diagram and parts list 8.
Special adjustment for measuring and adjusting CO2 levels 9 Special adjustment for measuring and adjusting CO2 levels The CO2 can only be adjusted by a certified gas technician with a calibrated CO2 analyzer. Caution: One factor that may affect CO2 levels is improper gas pressure. Please see Chapter 2.
Special adjustment for measuring and adjusting CO2 levels D. Returning to Service: 1. Return slotted cover to original position. 2. Reinstall Torx cover. 3. Remove CO2 analyzer probe and reinstall plug in exhaust collar. 4. Turn ON/OFF switch to the OFF (O) position and then back to the ON (I) position. 5. Heater is ready for normal operation. Without Front Cover With Front Cover Nat. Gas Nat. Gas max. input P1 9.1 ± 0.1 % 9.7 ± 0.1 % min. input P2 9.4 ± 0.1 % 9.7 ± 0.1 % LP Gas LP Gas max.
Protecting the environment 10 Protecting the environment Packing The packing box may be fully recycled as confirmed by the recycling symbol . Components Many parts in the heater can be fully recycled in the end of the product life. Contact your city authorities for information about the disposal of recyclable products. Saving water resources: B Make sure you close all the taps after any use. Avoid leaving the taps dripping. Repair any leaking tap.
Twelve Year Limited Warranty 11 Twelve Year Limited Warranty General Service Labor Costs Aquastar water heaters are warranted by the Manufacturer (BOSCH) through Controlled Energy Corp. Controlled Energy Corp. (CEC) will furnish a replacement heat exchanger and will furnish a replacement of any other part which fails in normal use and service within the applicable periods specified below, in accordance with the terms of this warranty.
Ins ta ller C heck lis t, to be performed by ins ta ller upon ins ta lla tion S erial Number ___ ___ ___ ___ ___ ___ ___ ___ (8 digit serial number is located on rating plate on right side panel) G as Pressure R eading* S tatic__________ O perating__________ B uilding W ater Pressure __________ R ange if on W ell system __________ Average W inter Temperature __________ Average S ummer Temperature __________ Installing C ompany _____________________________________________ Installer name ______