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11

Installation 

SNA-Series Tankless Heater

Keltech • 

215-1815 Rev. B; ECN 130011 

10/17/2014

Output heating capacity is reduced if these heaters are installed on 415V, 400V or 380V 3-ph . 
Contact the factory to supply this information . Satisfactory performance of the heater is dependent upon a specific 
flow rate vs temperature rise capability . If the desired temperature is not achieved, please verify the following:

1 .  Circuit breaker is on and rated for the maximum power draw .
2 .  Heater is drawing the proper current for the supply voltage on all 3 phases .
3 .  All 3 phase indicator lights are lit (not flashing) indicating maximum power draw and maximum 

amperage is being drawn .  

4 .  Flow rate and temperature rise requirements are compatible with the heater specifications .  
5 .  Verify there is no additional supply of cold water entering the line downstream of the heater .  

TepidGuard

 Flow Conditions

When a low flow condition (less than 15 gpm) occurs, such as operation of the eye/facewash individual elements are 
energize to supply water for the eye/facewash and/or drench hose . One set of PID values is selected on the controller 
for accurate temperature control at low flow conditions .
When the heater detects high flow conditions (greater than 15 gpm), all elements are energized . A second set of PID 
values is selected on the controller for accurate temperature control at high flow conditions . 
When the heater shuts down or switches from high to a low flow condition, the purge valve opens and purges the 
heater of latent (excess) heat . This anti-scald feature works both actively at the end of each shower or passively 
if sitting in an environment that may exceed the 95°F (35°C) . This TepidGuard™ system ensures safe water 
temperatures at both the eyewash and shower stations .

Product Options 

AL3 & AL3-SL 

Temperature Alarms: Alerts you to an over or under temperature situation . 

GF 

(Ground Fault): Detects electrical leakage from external sources to protect equipment, electronics, and the heat 

exchanger from being damaged in the event of a power fault . After turning on water, then power, test ground fault:

1 .  Press GF Test button .  
2 .  Watch for ground fault light to illuminate and Bank Ready light(s) to shut off . The Ground Fault system is active 

and in working order .  

3 .  Press the GF Reset button, hold for 2 seconds and release to reset ground fault .

NOTE: If a trip occurs under normal operation DO NOT RESET Ground Fault without evaluation and service. 
NOTE: Normal state is Ground Fault light OFF, Bank Ready lights ON.

ENHT Freeze Protection (ENHT & ENHT30)

: ENHT offers protection to -20°F (-28°C) . The ENHT30 offers protection to 

-30°F (-34°C) . Each level of protection utilizes the normal heater supply voltage . No additional dedicated circuit to the unit 
is required during field installation . Freeze protection (ENHT option) includes an internally insulated NEMA 4/4X enclosure 
and thermostatically controlled forced air heater to maintain internal temperatures above freezing . ENHT options also 
include a connection point for DCS monitoring . In the event of a power interruption or ENHT system failure when internal 
enclosure temperatures reach 40°F (4 .4°C) or lower, the unit will notify a facilities control/monitoring system that the unit is 
unable to maintain freeze protection . Regardless of state of power to the unit, this warning notifies maintenance personnel 
and provides an opportunity to correct the condition before any damage occurs to the unit .

NOTE: With this option, three phase power must be continuously applied to the heater for the internal freeze protection 

heater to operate properly and provide protection. If three phase power cannot be continuously applied, the heat 
exchanger must be completely drained of water and electrically locked out or damage from freezing may occur. 
Use Start Up procedure to restart this equipment. This option does not require a separate electrical circuit.

WARNING!  Failure to maintain power at all times may result in damage to the heater and void the warranty. 

Please utilize the temperature sensor contacts (N.O.) that can provide a signal to a remote 
device, DCS monitoring or BMS (Building Management System) signal. When temperature inside 
the cabinet drops below 40°F (4°C) operation of the system should be verified.

…continued on next page

Summary of Contents for SNA-36

Page 1: ...ptions 11 12 Maintenance 12 Troubleshooting 12 13 Special Installation Operating Instructions 14 17 IMPORTANT Read this entire installation manual to ensure proper installation When finished with the...

Page 2: ...ntended service Frequency of cleaning and inspection depends upon local water conditions For heaters with adjustable output temperatures check and adjust as needed at initial installation and on a qua...

Page 3: ...eaters from Rain or other falling precipitation via tarp or other waterproof media Runoff and accumulation of groundwater from any source that may exceed 1 inch NOTE For heaters with ENHT freeze prote...

Page 4: ...mperature relief valve on hot water outlet immediately following the union NOTE Valve must empty into a drain See Figure 2 B Remove air by re installing drain plugs and open inlet supply valve to appl...

Page 5: ...stem or at any drop to eliminate trapped air Components Needed 5 Union 1 1 4 Shutoff Valve Pressure and Temperature Relief Valve 150 psi Y Strainer 100 mesh or Inline Filter 150 microns 2 Gate or Ball...

Page 6: ...rating for each heater CAUTION To avoid damage to the electronics or internal wiring do not perform any brazing or sweat soldering inside the enclosure ELECTRICAL SPECIFICATIONS FOR HEATER PHASE 3 Mo...

Page 7: ...ief valve on outlet if required by local or national plumbing codes If the hot water process is not at the highest point in the plumbing loop then an automatic air vent valve must be added at the high...

Page 8: ...et shower etc then flush the system for 5 minutes to ensure all air is purged from the system CAUTION Failure to bleed air properly will damage elements and cause heater malfunction Be sure that plumb...

Page 9: ...me page Advance Key Advances through parameter prompts Auto Man Off C r71 Turns Control Loop On Manual Off Disabled on SNA Models XX X h Pr1 Heater Power Disabled on SNA Models no AUt1 Autotune Contac...

Page 10: ...e of approximately 10 psi For example if the high limit pressure is 40 psi adjust the low limit pressure to 30 psi with the pressure switch located on the supply pump Heater will not energize heating...

Page 11: ...fault After turning on water then power test ground fault 1 Press GF Test button 2 Watch for ground fault light to illuminate and Bank Ready light s to shut off The Ground Fault system is active and...

Page 12: ...he heat exchangers may trip at temperatures below 32 F on heaters equipped with ENHT or ENHT30 Manual resets are set to trip at 100 F 38 C Heat trace installed on connected piping can heat water to te...

Page 13: ...dicated Bank 1 2 on the front bezel Bank 1 on the FLCB Bank 3 4 on the front bezel Bank 2 on the FLCB If the light is off and there is power on Check if water temperature is greater than 175 F Decreas...

Page 14: ...nlet fitting here FIGURE 6 EXP2 EXP2LC Installation Notes 1 Any tubing conduit or fittings connected to the Pressurized Enclosure PE must conform to local codes for flammability ratings 2 All egress i...

Page 15: ...ure and the protective gas supply The alarm actuator shall be mechanical pneumatic or electrical Electrical alarms and electrical alarm actuators shall be approved for the location in which they are i...

Page 16: ...roved the interior of the PE is gas free and checked that the Pressurized indicator is green Commissioning Test Commissioning Leakage Compensation LC and Continuous Flow High Purge Keltech Options EXP...

Page 17: ...larms function correctly Check the Relief Valve and any other Spark Arrestors Remove any debris or corrosion or replace the Spark Arrestor Check the condition of the air supply filter element Clean or...

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