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INSTALLATION AND OPERATING INSTRUCTIONS
FOR AUTOMATIC INSTANTANEOUS TYPE WATER HEATERS
FOR USE WITH NATURAL AND LIQUEFIED PETROLEUM GAS
MODEL 170 VP
Suitable for water (potable) heating and space heating
WARNING: If the information in this manual is not
followed exactly, a fire or explosion may result
causing property damage, personal injury or death.
FOR YOUR SAFETY
Do not store or use gasoline or other flammable,
combust
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TABLE OF CONTENTS Specifications .............................................................................. Page 3 Rules for Safe Operation ............................................................. Page 4-5 General Overview of Aquastar .................................................... Page 6 Locating the Heater for Safe Proper Combustion........................ Page 7 Installation ................................................................................... Page 8 Connecting Gas
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AquaStar 170 VP Specifications: Gas input ........................... max: 165,000 Btu min: 56,400 Btu Water Connection................... 3/4" NPT fitting H x W x D ...........................35.5"x22.5"x13.5" Vent ............................................................. 6" Gas Connection................................3/4" NPT Min. Water Pressure............................. 15 Psi Max. Water Pressure.......................... 150 Psi Shipping Weight .................
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CAUTION: RULES FOR SAFE OPERATION If you are using the AquaStar for combined space heating and potable water heating (see schematic diagram below), all piping and other components connected to the system must be suitable for potable water, (b) toxic chemicals such as those commonly used for boiler treatment to prevent corrosion and freezing must not be introduced into the system, and (c) if the space heating requires water temperatures higher than those required for domestic, potable water, a
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RULES FOR SAFE OPERATION 1. You should follow these instructions when 6. Keep water heater area clear and free from you install your heater. combustibles and flammable liquids. Do not In the United States: The installation must con- locate the heater over any material which might form with local codes or, in the absence of lo- burn, such as carpet. cal codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. 7. Correct gas pressure is critical for the opti- In Canada: The insta
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Fig. 2 Parts of AquaStar 170 X A W U B C V D T E S F G I R M H K Y J L P A. Hanging frame and back support L. Manual gas valve B. Thermostatic sensor M. Cold water inlet C. Heat exchanger P. Pilot starting button D. Thermocouple R. Water valve E. Burners S. Pilot filter F. Burner manifold T. Pilot G. Manifold Gas pressure testing nipple U. Overheat sensor 130 °C H. Temperature selector knob V. Domestic Hot Water (DWH) sensor 90 °C I. Hot water outlet W. Draft hood J. Thermostat adjustment
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LOCATING YOUR HEATER FOR SAFE PROPER COMBUSTION Carefully select the location of your new heater. For your safety and for proper heater operation, you must provide an abundant supply of combustion air and install a proper vent. The heater may still operate even when improperly installed. However, an improper installation will be less efficient and may damage the heater. Improper installation can even result in human sickness or death due to oxygen deprivation and carbon monoxide poisoning.
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8. This heater is not approved for closet instal- mounting screws which are located in the plas- lation. For alcove installation, maintain the fol- tic bag on the side panel of the heater. Use a lowing minimum clearances from all construc- 1/8 inch drill if screws are to go directly into tion for servicing and proper operations: studs; otherwise size the holes for the plaster anchors (also located in plastic bag). Tighten Alcove screws to the wall allowing just enough room A. Top 12 inches be
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NOTE: The regulator supplied with the The location of the relief valve must be readily heater is an appliance level regulator de- accessible for servicing or replacement. To ac- signed for low inlet pressure (less than 1/2 commodate the pressure relief valve, a suitable LB or 15"W.C.). DO NOT connect to an un- fitting connected to an extension of a "T" fitting regulated or high pressure propane line. can be sweated to the line. Make the T-fitting When your connections are made, check for ext
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Therefore, when operating at less than full An "on demand" instantaneous heater like the output, the heater does not have its full heating AquaStar may have frequent operating cyles of capacity to warm the flue pipes to create a less than a minute. If venting and air supply are natural draft. Most gas appliances have longer inadequate to provide a positive draft as soon duty cycles than are typical of instantaneous as the heater turns on, the heater may not remain heaters. For many gas a
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LIGHTING INSTRUCTIONS 1. STOP! Read the safety information In the United States: The installation must con- form with local codes or, in the absence of lo- above. cal codes, the National Fuel Gas Code ANSI 2. Push in gas control handle slightly and Z223. 1/NFPA 54. In Canada: The installation should conform with CGA B149 INSTALLATION turn clockwise to "RED DOT" posi- tion. CODES and/or local installation codes. If knob does not pop out when released, stop 3. Wait five (5) minutes to cl
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SETTING THE WATER TEMPERATURE The AquaStar 170 water heater contains a flow very hot water and then mix in cold. It just doesn't make sense to overheat water then mix restrictor set at 4 1/4 gpm. Its purpose is to assure that the hot water temperature will al- in a lot of cold water to cool it off. Remember you cannot run out of hot water with an ways be within a comfortable range regardless of how high one may turn on the hot water fau- AquaStar, so set the dial for the (exact)
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valve discharges by itself, a problem exists and Wash the stainless steel burners if they are dirty. service is required. This could be due to a de- Burners can be detached from the heater by fective relief valve or to overheating. removing the pilot tube and the thermocouple assembly and disconnecting the Energy-Cut- Pilot Flame: The pilot flame should burn with Off switches. a clean sharp blue flame and should resemble (Do not lose the retaining clip) The burners Fig.4 below. If the flam
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Mineral Scale Buildup:AquaStars, when operated at high temperatures or in hard water areas, may need periodic descaling. To check the inside of the heat exchanger for scaling, remove the thermostat sensing element from inside the heat exchanger (B), page 6. If you note mineral buildup in the heat exchanger, flush it with a descaling solution. Consult your dealer or call CEC for instructions. TROUBLE SHOOTING Letter references, e.g. "L" in this section refer 2. In-line AquaStar gas regulator j
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4. Pilot orifice may not be correct for your 3. Poor circuit connections at the ECOs type of gas. (Energy Cut-Off switches) Pilot orifice is stamped: #15 for LP and #27 for Oxidation or looseness of the ECO screw con- NG. nections can result in millivolt current loss through the thermocouple safety circuit. Clean 5. Air in the Gas Line terminals with very fine sand paper or an eraser Note: Normally this is a problem only at the time and re-tighten terminal screws. (See letter V in of installat
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Attach a multimeter lead on the thermocouple not occur. A plumbing crossover can be caused by a bad washer at a single lever faucet, copper tubing below the head, and attach the other meter lead on the ends of both the wires. incorrect piping or an automatic mixing valve in Light the pilot and take a reading on the meter. the line which permits hot and cold water to mix If it reads less than 24 mv, replace the thermo- in the plumbing. The crossover will create a couple. If the reading is 24 m
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2. Gas pressure too low within which the heater can maintain tempera- Very low gas pressure may be caused by low ture. See flow chart on Page 18. AquaStar delivered gas pressure, by a jammed gas regu- water heaters have a (removable) flow restrictor lator or by undersized gas lines. If the gas lines to assure that the maximum volume flowing are undersized, there may still be the specified through the heater remains in the range that the static gas line pressure. However, when the heater can
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when mixing cold water at the tap, the lower 6. Parts in water flow valve (#38411) are cor- water pressure on the hot side may be momen- roded tarily overpowered by a much higher cold wa- The gas valve will not open fully if water valve ter pressure, which may cause the AquaStar parts are corroded. Replace both parts in wa- burners to shut down. Make sure faucet aera- ter valve (#38475, 33071). tors or shower heads are free of minerals. HOT WATER TEMPERATURE FLUCTUATES Check that the flow r
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CLEANING THE PILOT ASSEMBLY suspect that it might be partially obstructed. If you do AquaStar models 80/125/170 not have a replacement orifice, you may blow through it or use a non-residue aerosol cleaning agent (like A. Removing Pilot that used for electronics) can be sprayed through the 1. Hold Gas Pilot Filter Housing in place with one orifice. wrench. 5. Clean any combustion residue from the Pilot Burner 2. Unscrew Pilot Tube nut with second wrench. tip. Make certain that both holes
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CALIBRATION AND THERMOSTAT TEST SYMPTOMS OF A DEFECTIVE OR IMPROPERLY CALIBRATED THERMOSTAT: The hot water is too hot. Usually this results in the heater shutting down on overheat safety. The pilot frequently goes out and needs to be relighted. PROCEDURE TO CALIBRATE THERMOSTAT (See diagram for correct location of screw to recalibrate) 1. Turn calibration screw in clockwise all the way, compressing the spring. 2. Back out screw 1 1/2 full turns. When set at the factory, the space from top to bo
