TM ® Indirect-Fired Water Heaters Product Manual • Installation • Maintenance • Startup • Parts ® User — Read important user safety information found on page 3, page 24 and page 25. Installation and service should only be performed by a qualified service technician. Retain this manual for future reference. This manual must only be used by a qualified heating installer/service technician. BEFORE installing, read all instructions in this manual and all other information shipped with the water heater.
AQUA PLUS indirect-fired water heaters — Product Manual Contents Please read before proceeding 3 When servicing water heater . . . . . . . . . . . . . . . . . . . . 3 Operating restrictions . . . . . . . . . . . . . . . . . . . . . . . . 3 Boiler water restrictions . . . . . . . . . . . . . . . . . . . . . . 3 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AQUA PLUS indirect-fired water heaters — Product Manual Please read before proceeding Hazard definitions The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or to important information concerning the life of the product. Indicates presence of hazards that will cause severe personal injury, death or substantial property damage.
AQUA PLUS indirect-fired water heaters — Product Manual Pre-installation Codes Figure 1 Clearance recommendations 1. Installation must conform with instructions in this manual and, where applicable: • local, state, provincial, and national codes, laws, regulations and ordinances. • in Canada — B149.1 or B149.2 Installation Code. 2. AQUA PLUS water heaters are exempt from ASME Section VIII, Division 1 Code construction per Interpretation VIII-1-86-136. Check with local codes for applicability. 3.
AQUA PLUS indirect-fired water heaters Pre-installation — Product Manual (continued) Domestic water piping requirements 1. Install unions on all piping for easy removal of water heater. 2. Use dielectric unions or couplings to protect hot and cold water fittings from corrosion when connecting dissimilar materials such as copper and galvanized iron pipe. 3.
AQUA PLUS indirect-fired water heaters — Product Manual Domestic water piping Piping overview Figure 2 DHW piping THERMAL Expansion tank — If a backflow preventer, check valve, or pressure reducing valve is piped on cold water inlet of water heater, you must install an expansion tank on cold water supply line to prevent normal thermal expansion from repeatedly forcing open T&P relief valve.
AQUA PLUS indirect-fired water heaters Domestic water piping — Product Manual (continued) LEGEND for Figure 2, page 6 Domestic water supplied to fixtures that could pose an injury hazard due to high temperature, such as showers and faucets, should be equipped with a temperature regulating device, such as an anti-scald mixing valve. When the supply pressure is higher than 70 PSIG, install a pressure reducing valve on cold water supply line to prevent water loss through T&P relief valve.
AQUA PLUS indirect-fired water heaters — Product Manual Recirculation Massachusetts code applications require recircu- lation piping or heat-traced piping if the distance from the water heater to the furthest fixture exceeds 100 feet. Maintaining domestic water temperature in the supply piping 1. Recirculation is used to reduce wait time for water use, to minimize hot water and energy waste caused during the waiting period, and to prevent degradation of the system supply water temperature.
AQUA PLUS indirect-fired water heaters Recirculation Figure 4 — Product Manual (continued) Time lag to obtain hot water at fixture for branch lengths of 10 and 25 feet (ASPE Domestic Water Heating Design Manual) Time in seconds required to get hot water at fixture (from ASPE) Fixture flow rate (GPM) - 0.5 Piping length (feet) Copper pipe Steel pipe CPVC pipe 1.5 2.5 4.
AQUA PLUS indirect-fired water heaters Recirculation — Product Manual (continued) Components Figure 6 Recirculation piping Circulator (Figure 6, item 1) 1. Little flow is required to maintain a temperature in the piping. 2. Size of circulator depends on minimum flow requirements of the tempering valve. 3. Minimum flow rates of the tempering valve must be maintained. Aquastat (Figure 6, item 2) 1. Used to control the on-off position of the circulator.
AQUA PLUS indirect-fired water heaters — Product Manual Boiler-side piping Figure 7 Zoning with circulators — direct-connected system piping Notes • • • Place circulators at beginnings of zones. Placing them at the ends of zones could result in heating idle zones. Size manifold piping for total flow of all zone circulators. Locate flow / check valves as close as possible to water heater boiler side connections — to reduce heat loss between cycles.
AQUA PLUS indirect-fired water heaters Boiler-side piping Figure 8 — Product Manual (continued) Zoning with circulators — primary/secondary system piping Notes • • • Place circulators at beginnings of zones. Placing them at the ends of zones could result in heating idle zones. Size manifold piping for total flow of all zone circulators. Locate flow / check valves as close as possible to water heater boiler side connections — to reduce heat loss between cycles.
AQUA PLUS indirect-fired water heaters Boiler-side piping Figure 9 — Product Manual (continued) Zoning with zone valves — direct-connected system piping Notes • • • Place circulators at beginnings of zones. Placing them at the ends of zones could result in heating idle zones. Size manifold piping for total flow of all zone circulators. Locate flow / check valves as close as possible to water heater boiler side connections — to reduce heat loss between cycles.
AQUA PLUS indirect-fired water heaters Boiler-side piping — Product Manual (continued) Figure 10 Zoning with zone valves — primary/secondary system piping Notes • • • Place circulators at beginnings of zones. Placing them at the ends of zones could result in heating idle zones. Size primary piping for total flow of all zone circulators. Locate flow / check valves as close as possible to water heater boiler side connections — to reduce heat loss between cycles.
AQUA PLUS indirect-fired water heaters Boiler-side piping — Product Manual (continued) Figure 11 Dedicated single-boiler piping Notes • • • Place circulators at beginnings of zones. Placing them at the ends of zones could result in heating idle zones. Size manifold piping for total flow of all zone circulators. Locate flow / check valves as close as possible to water heater boiler side connections — to reduce heat loss between cycles.
AQUA PLUS indirect-fired water heaters Boiler-side piping — Product Manual (continued) Figure 12 Multiple water heaters — domestic water piping Failure to install automatic mixing valve where recommended can result in severe personal injury or death. 1. This drawing is conceptual only. It shows representative piping components and layout. Weil-McLain does not represent that this drawing meets any particular mechanical or building codes.
AQUA PLUS indirect-fired water heaters Boiler-side piping — Product Manual (continued) Figure 14 Multiple water heaters and dedicated multiple boilers — boiler water piping Notes • See legend and details in Figure 12, page 16. 1. This drawing is conceptual only. It shows representative piping components and layout. Weil-McLain does not represent that this drawing meets any particular mechanical or building codes.
AQUA PLUS indirect-fired water heaters — Product Manual Connecting to a low-pressure steam boiler Special considerations When designing steam and domestic hot water systems, there are some key issues that must be taken into consideration during the initial design phase. By designing the system properly from the start, you can avoid problems and have a hot water loop in a steam boiler system. • • • • • • • • The domestic water demand should preferably not exceed 1/3 of the steam boiler capacity.
AQUA PLUS indirect-fired water heaters — Product Manual Connecting to a low-pressure steam boiler (continued) Figure 16 Low pressure steam boiler application — Domestic water heating using water pumped from steam boiler Notes • Locate flow / check valve as close as possible to water heater boiler side connections — to reduce heat loss between cycles. Use memory stop valve 7 to blend some of the water returning to the boiler with the hot water coming from the boiler.
AQUA PLUS indirect-fired water heaters — Product Manual Boiler-side wiring and controls Electrical shock hazard — Can cause severe personal injury, death or substantial property damage. Disconnect power before installing and / or servicing. Wiring requirements 1. All wiring must be a minimum of 18 gauge and installed in accordance with: • U.S.A. — National Electrical Code and any other national, state or local code requirements having jurisdiction. • Canada — CSA C22.
AQUA PLUS indirect-fired water heaters — Product Manual Wiring — zoning with circulators Figure 18 Typical wiring — zoning with circulators — DHW priority with Weil-McLain WMCR Circulator Zone Controller Notes • • Also refer to the WMCR manual and Weil-McLain Boiler Zone Wiring Guide for further details. Refer to Wiring requirements on page 20. System piping • • Figure 7, page 11 Figure 8, page 12 1. This drawing is conceptual only. It shows representative components and wiring.
AQUA PLUS indirect-fired water heaters — Product Manual Wiring — zoning with zone valves Figure 19 Typical wiring — zoning with zone valves — DHW priority with Weil-McLain WMZV Zone Valve Zone Controller Notes • • Also refer to the WMZV manual and Weil-McLain Boiler Zone Wiring Guide for further details. Refer to Wiring requirements on page 20. System piping • • Figure 9, page 13 Figure 10, page 14 Install all zone valves per valve manufacturer’s instructions. 1. This drawing is conceptual only.
AQUA PLUS indirect-fired water heaters — Product Manual Water heater filling and start-up The installation and water chemistry must meet the requirements below. Failure to comply could result in damage to the water heater, causing possible severe personal injury, death or substantial property damage. Boiler water restrictions • • • • Thoroughly flush the boiler system (without water heater connected) to remove sediment.
AQUA PLUS indirect-fired water heaters — Product Manual Water heater temperature adjustment General notes • • • Household water usage patterns will affect water temperature at any faucet or shower. • Occasionally check temperature at each point of use, then adjust thermostat accordingly. • Always recheck temperature after adjusting thermostat. When hot water is used in repeated small quantities, a “stacking” effect can develop in hot water tank.
AQUA PLUS indirect-fired water heaters — Product Manual Water heater maintenance Boiler water — read and comply with all requirements under “Boiler water restrictions,” page 3. Figure 21 T&P valve operation Water from opened drain valves, unions and other connections may be extremely hot. To avoid severe personal injury, death or substantial property damage: • Tighten all drain hose connections. • Direct hot water away from all persons.
AQUA PLUS indirect-fired water heaters Water heater maintenance and their frequencies, including any not listed in the following paragraphs. — Product Manual (continued) Figure 22 Inspection hatch assembly (hatch cover shown transparent) The purpose of the magnesium anode is to reduce the damaging effects of aggressive water on the water heater. Aggressive water will cause the anode to erode. The anode must be inspected at least annually to determine whether a new anode should be installed.
AQUA PLUS indirect-fired water heaters — Product Manual Troubleshooting Troubleshooting procedures Follow the troubleshooting guidelines step by step. Always double-check your results. Skipping or not completing steps can lead to wrong conclusions, repeated callbacks to the jobsite and unhappy customers. Preparation for troubleshooting Tools needed ❏❏ Electrical meter to measure voltage and continuity. ❏❏ Pressure gauge (such as Watts #276H300 test gauge). ❏❏ Temperature gauge. ❏❏ Stopwatch.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Figure 23 Typical problems and causes and page location for details Problem Insufficient hot water Check possible causes 1 2 3 4 Undersized water heater? Boiler system improperly sized? Check component parts. Check boiler operating temperatures. Page 5 Check location of flow control devices. 6 Check for air in the system. 7 Clean the boiler water system. 8 Check tank thermostat setting.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Insufficient hot water 1 Undersized water heater? • There are many methods of sizing various applications, i.e. ASHRAE sizing tables or ASPE domestic water heating design manual. • Confirm the water demand required for the application. • Confirm the flow rates of the fixtures. • For example, was the tank sized for shower heads at 2.0 gpm, while the actual heads are 5.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Insufficient hot water (continued) • Is the circulator between the boiler and the water heater properly sized to provide enough flow for maximum BTU transfer? Check the table below: Pipe size Flow, GPM MBH Pipe size Flow, GPM MBH ¾” 1 to 4 50 to 100 1 ½” 14 to 22 200 to 450 1” 4 to 8 100 to 180 2” 22 to 45 300 to 650 1 ¼” 8 to 14 160 to 300 3 Check component parts.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Insufficient hot water (continued) 4 Check boiler operating temperatures. • If possible, increase the boiler operating temperature to 180°F or 200°F. • Maintain a minimal temperature in the boiler during non-heating seasons. • A boiler typically has a higher standby loss than the indirect water heater.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Excessive domestic water temperature 1 Reduce stacking. • Excessive water temperature is usually the result of stacking within the water heater. • Stacking is the occurrence of various water temperatures layering within the water heater with the hottest water in the uppermost layer.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Boiler relief valve lifting or weeping 1 Undersized expansion tank? • Insufficient allowance for expansion on the boiler side can cause the boiler pressure relief valve to lift. • The additional quantity of boiler water contained in the outer tank must be considered when sizing the boiler side expansion tank. AQUA PLUS model Boiler side volume — gallons 35 1.6 45 1.9 55 2.2 85 2.5 105 3.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Temperature/pressure relief valve lifting or weeping 1 Undersized or missing domestic water side expansion tank? • Is there a thermal expansion tank installed on the domestic supply piping and is it properly sized? • A thermal expansion tank is required if the domestic supply piping includes a backflow preventer or pressure reducing valve.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Water on the floor near the tank 1 Check for leaks from sources other than the water heater. • Check for possible water seepage through foundation cracks. Did the water appear after a heavy rain? 2 Is the source of water from the T&P relief valve? • Place a bucket under the discharge piping of the T&P relief valve and monitor it for a day or two. This is a procedure that can be done by the homeowner.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Rapid decay of magnesium anode 1 Anodes last less than two years The purpose of the magnesium anode is to reduce the damaging effects of aggressive water on the water heater. Aggressive water will cause the anode to erode. The anode must be inspected at least annually to determine whether a new anode should be installed. Severe or rapid deterioration of the anode indicates very aggressive water.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Water quality problems 1 Water smells like “rotten eggs.” • The most common cause of water to smell like “rotten eggs” is a non-toxic sulfate reducing bacteria. • The bacteria usually enters into the water system through a break in the supply piping or during construction/maintenance of the supply piping.
AQUA PLUS indirect-fired water heaters Troubleshooting — Product Manual (continued) Water quality problems (continued) • • • This is similar to the reaction that occurs as air bubbles form on the walls of a pan shortly before the water begins to boil. The release of dissolved gas can also create air pockets and air locks in the water system piping. This can cause spurts of air or gases when opening the hot water faucet.
AQUA PLUS indirect-fired water heaters — Product Manual Replacement parts Figure 24 Water heater replacement parts Item Description 1 2 3 4 5 Magnesium anode replacement kit (includes anode, o-ring, insulating washer and brass bushing) Thermostat repair kit Top plastic cap replacement kit Bottom plastic cap replacement kit (plastic cap and 4 screws) Leveling leg replacement kit (4) Size/Model AQUA PLUS Weil-McLain Part Number 35/45/55 633500014 85 633500015 105 633500016 Aqua PLUS Reside
AQUA PLUS indirect-fired water heaters — Product Manual ® AHRI ratings AHRI certified ratings Model AQUA PLUS 35 180°F boiler water entering | 58°F to 135°F domestic water First Hour Rating Continuous Draw Rating Minimum Heat Output Rate GPH GPH Btu/hr 230.0 203.9 134,477 Minimum Heat Source Heat Source Friction Loss Flow Rate GPM 14.0 Feet w.c. 5.4 First Draw Rating Standy Loss GPH Degrees F per hour 26.1 The ratings in this table are certified by AHRI.
AQUA PLUS indirect-fired water heaters — Product Manual Ratings with 200°F boiler supply water For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at 200°F, and the boiler water flow rate must be no less than given in the tables below. (For Ultra Gas boiler, Ultra Oil boiler or GV90+ boiler applications, with supply water at 190°F, see the ratings in the boiler manual.
AQUA PLUS indirect-fired water heaters — Product Manual Ratings with 190°F boiler supply water For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at at least 190°F, and the boiler water flow rate must be no less than given in the tables below.
AQUA PLUS indirect-fired water heaters — Product Manual Ratings with 180°F boiler supply water For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at at least 180°F, and the boiler water flow rate must be no less than given in the tables below.
AQUA PLUS indirect-fired water heaters — Product Manual Dimensions Figure 25 Dimensions and ratings — AQUA PLUS indirect-fired water heaters 1 Boiler water inlet (see table for size) 2 Boiler water outlet (see 3 4 5 6 7 8 9 10 Storage Model AQUA PLUS Connections Dimensions (inches) Ship. weight DHW Boiler In/Out water & In/Out Recirc. DHW side Boiler side Gallons Gallons Inches NPT 35 29.6 1.6 45 39.