WARNING CAUTION WARNING - Hydrolevel

1 1126 bailey Road, North Haven, CT 06473 Phone (203) 776-0473 FAX (203) 764-1711 3250-PlusTemp Limit / LWCO Controlwith Thermal Targeting for Water Boilers120 VAC Operating VoltagePATENT NO. 8,931,708; 8,844,834;7,891,572; others pendingWARNINGE lectrical shock prevent electrical shock, death orequipment damage, disconnect power supply beforeinstalling or servicing control. Only qualified personnel may install or service this control inaccordance with local codes and ordinances. Read instructions completely before prevent seriousburns, boilershould be thoroughly cooled before installing orservicing pipes/water heating systems are prone to shut down as a result of power or fuel outages, safety related fault conditions or equipment failure.

2 Installation of freeze protection monitoring or other precautionsis recommended for unattended dwellings in climates subject to sustained below-freezing Function DesignTemperature Limit ControlDesigned for cold start and tankless coil Water Cut-Off Provides protection against potentiallydangerous low water conditions when installed with the Hydrolevel Electro-Well (see page 2 for details).Boiler Reset Control Thermal Targeting On-board micro-processor adjusts boiler temperaturebased on heating demand. outdoor Reset Ready Compatible withHydrolevel OS-100 outdoor Sensor Kit(sold separately) for outdoor reset andwarm weather shut-down INSTRUCTIONS and OPERATING MANUAL Saves Fuel Features Thermal Targeting technology and Thermal Pre-Purge capability outdoor Reset Ready Provides outdoor Reset and Warm WeatherShut-Down capability with the addition of Hydrolevel OS-100 OutdoorSensor Kit (sold separately)

3 Universal Design Replaces common cold-start and triple-actionAquastats* Operating Indicators LEDs, Dynamic Display and Test Button providecontinual and on-demand status checks Prioritizes Domestic Hot Water Gives priority to low limit setting or tocalls from indirect water heater Reduces Condensation Holds circulator off until boiler reaches 125 F *Aquastatis a registered trademark of Honeywell International, THE CONTROLSTEP 1 Two mounting positionsare available on the back of the control(Fig. 1). Select which of the two positions(2 knockouts) is best for the location ofthe control. Remove the 2 Place control on the holding box against well nut,tighten well clamp screw. (Fig. 2)BACK OF FUEL SMART HYDROSTAT BOXFIG.

4 1 FIG. 3 FIG. 2 NOTE:In the case of space restrictions, the Fuel Smart HydroStat control may be mounted in a horizontal orientation without anyloss of function. Hydrolevel recommends vertical mounting, when possible, for proper orientation of LED MOUNTING KITSare available separately for mounting the Fuel Smart HydroStat control box in a remote location. Eachkit includes mounting hardware and a remote sensor. See page 16 for kit 3 Insert sensor ALLTHEWAY into well through the knockout (Aor B) you have chosen. (Fig. 3)IMPORTANTMake sure that the immersion well or Electro-Well is installed in the boiler manufacturer s designated temperature limit control tapping. NOTE: If installing an Electro-Well, pipe sealing compound should be used.

5 Teflon tape is not WELLSIMPORTANT: For proper operation of the low water cut-off function, theremust be a minimum of " clearance between the copper well tube and anysurface within the boiler. See Electro-Well models on page : When installed on a standard immersion well, the LWCO Active LED will not Smart HydroStat can be installed on an existing immersion well already in the boiler or on a Hydrolevel Electro-Well (sold separately). The low water cut-off function is automatically activated when installed on an Electro-Well . IMPORTANT: The control will not provide low water cut-off protection when installed on a standard immersion : Do not use heat-conducting Smart HydroStat installed with Hydrolevel Electro-Well Fuel Smart HydroStat installed with standard immersion wellIMPORTANT Sensor must be inserted all the way into the well for proper Electro-Well can be identified by the black electrical insulatoror, if installed, by the groove cut into the 1 Connect 120 VAC Hot to terminal VAC Neutral to terminal means and over-load protection as required (provided by others).

6 Select the Diagram thatMatches your System Configurationon Pages 4, 5 or 6 STEP 2 Connect the burner circuit to B1-B2. (B2 is neutral.)WARNINGE lectrical shock prevent electrical shock, death or equipment damage, disconnect power supply before installing or servicing this thermostat or end switch from zone relay or multi-zonepanel to circulator to end switchfrom indirect zone relay to Zone/IndirectSwitchdown to CIRCULATORMULTIPLE CIRCULATORSC onnect end switch from heating circulator relays or multi-zonepanel to end switch from indirect circulator relay Zone/Indirect Switch to :When installing with an indirect water heater, the Zone/Indirect Switch must be set in the Iposition. When set in the Iposition, calls to ZC-ZRwillbypass the Thermal Targeting feature and allow the boiler to fire to the high limit setting to heat the indirect tank.

7 The indirect signal must be separate from allheating zone signals. If you choose not to separate the indirect signal from the heating zones, the Economy Feature should be turned OFF to ensure that theboiler supplies adequate temperature to heat the indirect tank (see page 7).ZONE/INDIRECTSWITCHPOSITIONZONE/INDIR ECTSWITCHPOSITIONC onnect thermostat or end switch from zone relay or multi-zone panel to circulator to Switch up to end switch from circulator relay or multi-zone panel Zone/Indirect Switch up to Z. STEP 3A: HEATING ONLY No Indirect Water HeaterSTEP 3B: HEATING and Indirect Water HeaterSINGLE CIRCULATORMULTIPLE CIRCULATORSZONE/INDIRECTSWITCHPOSITIONZO NE/INDIRECTSWITCHPOSITIONNOTE:For proper operation of the boiler reset function, all heating thermostats must input to T-Tor ZC-ZRterminals as indicated below.

8 Jumping the T-T terminals and wiring the thermostat to the primary will override the economy shock prevent electrical shock, death or equipment damage, disconnect power supply before installing or servicing this control. CHOOSE OR BELOWCHOOSE FROM THROUGH BELOW OR ON PAGE 5 OR 65 NOTE: The wire from ZRto the hot terminal of the indirect circulator will ensurethat indirect calls will fire to limit and receive priority over heating CIRCULATORS Typical Zone Panel with Priority ZoneZONE/INDIRECTSWITCHPOSITIONZONE/INDI RECTSWITCHPOSITIONSINGLE CIRCULATOR Multiple Zone Valves including Indirect, No Zone Control PanelSTEP 3B: HEATING and Indirect Water Heater continuedNOTE:For proper operation of the boiler reset function, all heating thermostats must input to T-Tor ZC-ZRterminals as indicated below.

9 Jumping the T-T terminals and wiring the thermostat to the primary will override the economy shock prevent electrical shock, death or equipment damage, disconnect power supply before installing or servicing this control. MORENOTE: When using zone valves for both heat and indirect, the calls must be separated in order to prioritize indirect calls. This can beaccomplished by using a general purpose relay as shown above. However, for ease of installation, a zone control panel is recom-mended (see wiring diagram 7 on next page). SINGLE CIRCULATOR Typical Multiple Zone Valve Panel with Indirect6 ZONE/INDIRECTSWITCHPOSITIONZONE/INDIRECT SWITCHPOSITIONMULTIPLE CIRCULATORS Typical Three Zone Switch RelaySTEP 3B: HEATING and Indirect Water Heater continuedNOTE:For proper operation of the boiler reset function, all heating thermostats must input to T-Tor ZC-ZRterminals as indicated below.

10 Jumping the T-T terminals and wiring the thermostat to the primary will override the economy shock prevent electrical shock, death or equipment damage, disconnect power supply before installing or servicing this control. NOTE If a Zone Valve Control Panel has no priority zone: To ensure adequate boiler temperatureto satisfy the domestic hot water tank, it may be necessary to turn the Economy Feature off. NOTE: The wire from ZRto the hot terminal of the indirect circulator will ensurethat indirect calls will fire to limit and receive priority over heating s SR503 combines ZR amd THE CONTROLD ifferentials are automaticand will vary based on control settings and boilertemperature. Note: The high limit differentialcan be adjusted when the econ-omy feature is turned off.