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MODEL 250SX NG and 250SX LP
Temperature Modulated with Electronic Ignition
Suitable for heating potable water only
Not approved for space heating purposes
(Intended for variable flow applications with multiple tapping points)
250 SX NG
250 SX LP
Warning: If the information in this manual is not What to do if you smell gas
followed exactly, a fire or explosion may result
• Close gas valve. Open windows.
causing property damage, personal injury or death.
• Do not try to light any appliance.
Do no
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Index Index 1Warning 1Warning 2 Warning: If the information in this 2 Appliance details 4 manual is not followed exactly. A fire or 2.1 Features 4 explosion may result causing property 2.2 250 SX Specifications (Technical data) 4 2.3 Dimensions and Minimum installation clearances 6 damage, personal injury or death. 2.4 General rules to follow for safe operation 7 2.5 Proper location for installing your heater 7 2.6 Clearances 8 Warning: Improper installation, 2.7 Mounting installation 8 adjustme
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Warning Warning: Field wiring connections and electrical grounding must comply with local codes, or in the absence of local codes, with the latest edition of the National Electric Code, ANSI/NFPA 70, or in Canada, all electrical wiring must comply with the local codes and the Canadian Electrical Code, CSA C22.1 Part 1. Warning: Shock hazard line voltage is present. Before servicing the water heater, turn off the electrical power to the water heater at the main disconnect or circuit breaker. Fail
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Appliance details 2 Appliance details Maximum input 2.1 Features 175,000 Btu/h (51.2 kW) Parts Efficiency in % • Touch Pad interface control Recovery efficiency 86.5% • High power pre-mix compact burner with low Nox emissions Min. Output • Modulating Gas Valve with constant gas:air ratio 31,131 Btu/h (9.1 kW) control Temperature Control • Modulating water valve for improved comfort and temperature control. Selection range: 100°F (38°C) - 140°F (60°C) Default temperature: 122°F (50°C) Safety Sta
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Appliance details • Minimum recommended water pressure: 30 PSI UNPACKING THE 250 SX HEATER (2.07 bar) This heater is packed securely. • Connections: The box includes: – Bottom of heater • Pressure relief valve Combustion • Bracket for wall hanging the heater •NOx ≤ 55 ppm • Exhaust vent adaptor (with 4 screws and gasket provided) •CO ≤ 250 ppm • Combustion air inlet adaptor (with 3 screws and gas- •CO level set from factory, see chapter 9.1. 2 ket provided) Dimensions • Plastic decal shields fo
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Appliance details 2.3 Dimensions and Minimum installation clearances Fig. 5 Dimensions 1 Cover 2 On/Off switch 3 Reset button 4 LCD display 5 Program button 6 Temperature buttons Fig. 6 Minimum clearances Model 250 SX TOP (A) 12” FRONT (B) 4” BACK 0” SIDES 4” FLOOR (C) 12” VENT DIAMETER 3” Table 1 Minimum clearances 6 6 720 607 057
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Appliance details 2.4 General rules to follow for safe 2.5 Proper location for installing your operation heater B 1. You should follow these instructions when you Carefully select the location of the water heater. For install your heater. In the United States: The your safety and for proper heater operation, you must installation must conform with local codes or, in the provide combustion air to the heater and a proper absence of local codes, the National Fuel Gas Code exhaust vent system. ANSI
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Appliance details 2.6 Clearances The 250 SX is design certified for installation on a combustible wall (see 2.7 Mounting installation) provided the floor covering below the heater is noncombustible. For installations in an alcove or closet, maintain the minimum clearances to combustible and non-combustible materials listed below. See also Fig. 6. A. Top 12 inches (306 mm) B. Front 4 inches (102 mm) C. Back 0 inches D. Sides 4 inches (102 mm) E. Bottom 12 inches (306 mm) Clearances from any exhau
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Appliance details – b) In unconfined spaces in buildings of Establish vent clearances that comply with the vent conventional frame, masonry, or metal manufacturer's specifications. In all cases follow local construction, infiltration air is normally adequate to codes. See table 2. provide air for combustion. • Appliances located in confined spaces: The confined space must be provided with two permanent openings, one commencing within 12 inches (304.8mm) of the top and one commencing within 12 in
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Appliance details The maximum flue gas exhaust temperature on the 250 SX is 437°F (225°C) Venting Exhaust * Exhaust * Exhaust Combustion Combustion Vent pipe Vent pipe Options vent vent vent air pipe air pipe clearances clearances diameter maximum minimum diameter maximum within an within an and length length and material length unenclosed enclosed material space space Room 3 inch 26 feet (8 3 feet 3 inch PVC, 26 feet (8 ** See vent ** See vent sealed stainless m) with one a
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Appliance details The appliance should be located as close to the point page 24. See error code to confirm error, correct the of termination as possible. The maximum vent length is problem and then reset the heater before operating. 26 feet (8 m) with one 90 degree elbow. Subtract 2½ Attaching the exhaust and air inlet connection feet from the total vent length for each additional 90° adaptors to the top of the heater elbow used (a maximum of three 90° elbows are permitted in the total vent leng
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Appliance details Room sealed installation (TWIN PIPE SYSTEM) Open combustion installation (SINGLE PIPE SYSTEM) Fig. 12 Combustion air pipe: ≤ 26 ft (8 m) Exhaust vent pipe: ≤ 26 ft (8 m) If the total horizontal exhaust vent length in a side wall Fig. 14 installation is greater than or equal to 5 feet (1.5m), a condensate drain tube must be attached to the exhaust Exhaust vent pipe: ≤ 26 ft (8 m) collar. See page 14. If the total horizontal exhaust vent length in a side wall installation is grea
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Appliance details Recommended exhaust vent terminator position Fig. 16 Ref. Description Minimum distance Directly below an opening; operable windows, doors and any non- A 36 in mechanical fresh air openings Below a gutter, sanitary pipework or eaves 24 in B Below a gutter, sanitary pipework or eaves, protected by metal 12 in shielding C From any internal corner 12 in Above ground 12 in D* Above a paved sidewalk 7 ft From an opposing wall or structure facing the termination 24 in E From any othe
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Appliance details Supporting the exhaust vent system and the use If the total horizontal exhaust vent length in a side wall of an external condensate trap installation is greater than or equal to 5 feet (1.5m), a condensate drain tube must be attached to the exhaust External condensate traps collar. B A condensate trap must be used in any sidewall exhaust vent installations when the total vent length is ≥ 5 ft (1.5 m) OR the vent pipe passes through an unheated space (below 60F). See diagram bel
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Appliance details A condensate drain tube must be attached to the 2.10 Gas piping & connections exhaust collar of the heater for any vertically exhausted Before connecting the gas supply, check the rating vents, see page 14. 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.
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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 SX (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. Nominal Iro
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Appliance details load. Using a manometer, then measure the inlet gas 2.11 Gas line sizing pressure at the inlet gas pressure test port. See Fig. 23. B It is strongly recommended that the Natural Gas pipe Gas pressures lower than 5" W.C. for Natural Gas or be Black Iron pipe the entire distance from the 11" W.C. for LPG will result in insufficient degree rise outside meter to the inlet of the gas connection. ¾” to the hot water being used. See Gas Connections, Black Iron pipe up to 20 feet (6.1m
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Appliance details Connecting the pressure relief valve (PRV) 2.13 Water connections A listed pressure relief valve supplied with the heater When facing the heater, the ¾” cold water inlet is on the must be installed at the time of installation. No valve is bottom right and the hot water outlet is on the bottom to be placed between the PRV and the heater. No left. Install the heater centrally in the building if possible reducing coupling or other restriction may be installed and make hot water p
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Appliance details 2.14 Electrical connections 2.16 For your safety read before operating your water heater Warning: For safety reasons, disconnect the power supply to the Warning: If you do not follow these heater before any service or testing is instructions exactly, a fire or explosion performed. may result causing property damage, personal injury or loss of life. Warning: This heater must be A. This appliance is equipped with electronic ignition for electrically grounded in accordance lightin
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Appliance details NOTE: on a first time initial instal- lation or after gas line work has i been done, existence of air in the gas line will cause ignition delay when the hot water is turned on. This will result in an error (EA) on the units display screen. This is normal. When this occurs, leave the hot water running and wait 3-5 seconds, then reset the unit (Fig. 26, pos. 2). Wait for (EA) to disap- pear. The heater will begin to at- tempt ignition again, if the (EA) reappears the
