Seiko H855 Diver's Watch for Air Diving Instructions

Handling Cautions

WARNING: Please read the following instructions before use and strictly observe them. Mishandling of the product and misunderstanding of the displayed content may lead to a fatal or serious accident.

• When diving, never carry out operations other than those specified in this instruction manual.
• The diver's watch is an auxiliary instrument which mainly displays the passage of time and does not ensure the safety of a user. Use this watch while using the equipment (residual pressure gauge, water depth meter, etc.) required for safe diving.
• Never use this watch for "saturation diving" using helium gas.
• Do not dive using this product unless you have been properly trained in scuba diving, acquired the requisite experience and techniques for safe diving, thoroughly familiarized yourself with the operation and handling of this product, and inspect all functions of this product prior to each dive.

CAUTION: Please read the following instructions before use and strictly observe them.

• Inspect the following items before diving (excluding saturation diving): The watch is operating normally. The remaining battery level is sufficient and the mainspring is sufficiently wound. The rotating bezel turns smoothly. Screws of the crown and other parts are reliably tightened. No abnormalities such as flaws or cracks exist on the band or glass. The band is reliably fixed (with spring bar, buckle or other parts.) If any abnormality is observed in the above items, do not use this watch for diving.
• Do not operate the crown or buttons underwater.
• As the use environment of the diver's watch may affect not only the case or band but also the internal mechanism of the watch, it is recommended that you have your watch overhauled regularly once every three to four years.

Precautions for Diving

Before Diving

Check the following before diving:

• The time is correctly set.
• The seconds hand is moving at one-second intervals. The charge required symbol on the digital display is not lit or flashing. The seconds hand is not moving in two-second intervals, and has not stopped. If the charge required symbol on the digital display is lit or flashing, expose the dial to light to charge the watch.
• The rotating bezel turns smoothly. (The bezel rotation must not be too loose or too tight.)
• The crown and button screws are firmly tightened.
• There are no visible cracks or scratches on the crystal or watch band.
• The band is firmly attached to the watch (with spring bars, clamp or other parts.)

While Diving

Please observe the following cautions for use.

• The watch can be used for air diving within the water resistant range displayed on the dial.
• Take care not to bump the watch against hard objects such as rocks.
• Do not operate the crown or buttons underwater.
• Bezel rotation may become slightly harder in the water but this is not a malfunction.

After Diving

Please follow the care instructions below after diving.

• Rinse the watch in fresh water to wash out all seawater and wipe it thoroughly dry to prevent rust. Avoid pouring running water onto the watch directly from a faucet. Put some water into a bowl first, and then soak the watch in the water to wash it.

CAUTION: Depending on the environment where a diver's watch is used, its inner parts or movement as well as its case or band may be affected. It is recommended that you have your watch overhauled regularly once every three to four years.

Structure of the Case

In the following types of models, take care of the following issues in usage. The bezel or protective outer case is securely fastened to the watch with setscrews. Never loosen the setscrews.

CAUTION: Never loosen the setscrews used to fix the bezel or protective outer case. Doing so may cause damage or result in further loosening. If you find that the setscrews have become loose or are functioning abnormally, consult the retailer from whom the watch was purchased or SEIKO CUSTOMER SERVICE CENTER.

Characteristics

This solar watch is equipped with a water depth measurement function and diving log function.

• Water resistant performance for air diving: This watch is equipped with water resistant performance to be used in water for a long period of time with scuba diving tanks. (It cannot be used for saturation diving that uses helium gas.)
• Time and calendar function: The calendar is a fully automatic calendar with dates from 2001 to 2100. The day and date are displayed on the digital display screen.
• Local time display function: You can display your home time on the analog display and the local time on the digital display.
• Stopwatch function: The stopwatch can count up to a maximum of 100 hours.
• Alarm function: The watch is equipped with a daily alarm function that sounds every day at the set time (hour/minute).

Names of the Parts and Their Functions

• Analog display: Hour hand, Minute hand, Seconds hand
• Button A
• Digital display: Switching displays
• Button B
• Crown
• Button
• Rotating bezel

It is necessary to unlock the buttons and crown before operating each.

Screw Down Crown

The screw down crown features a mechanism that can securely lock the crown when it is not being operated in order to prevent any operational errors and to improve its water resistant performance.

• It is necessary to unlock the screw down crown before operating it.
• Once you have finished operating the crown, make sure to relock it.

To unlock the crown:

Turn the crown counterclockwise to unscrew it. Now the crown can be operated.

To lock the crown:

Turn the crown clockwise while gently pressing it in toward the watch body until it stops. After operating the crown, lock it.

Screw Lock Type Button

The screw lock type button features a mechanism that can securely lock the button when it is not being operated in order to prevent any operational errors and to improve its water performance.

• It is necessary to unlock the screw lock type button before operating it.
• Once you have finished operating the button, make sure to relock it.

To unlock the button:

Turn the button ring clockwise. Turning the button ring until you can see the entire check line and it stops will enable you to operate the button.

To lock the button:

Turn the button counterclockwise until it stops.

Switching Displays

When you press Button A, the digital display changes.

• Time display
• Calendar display
• Local time display
• Alarm display
• Stopwatch display
• Diving log display

If you hold down Button A, the display will change to the time. The display will not change to the time during diving mode, night diving mode, or when the crown is pulled out.

If the operation confirmation sound is set, a sound will play every time you change the display.

You can check the energy level by holding down Button B unless the digital display is showing the stopwatch, diving log, or is in diving mode.

If Button B is pressed when the digital display is not showing the stopwatch or diving log, the digital display light will turn on.

How to use the Diving Mode

When in diving mode, up to 100 diving records can be stored simultaneously, including diving information such as water depth and elapsed dive time. Recorded logs may be checked in the diving log display. In diving mode and in the diving log display, the light will not turn on when any of the buttons are operated. The time alarm and time signal will not sound during diving mode. Water depth measurement is possible up to a depth of 80 meters.

Recording a Diving Log

1. Unlock the button.
2. Press and hold Button B for more than two seconds. The watch will beep once and switch to diving mode. Keep pressing Button B, the watch will beep twice and switch to night diving mode. The light will flash for one minute immediately after switching to night diving mode. In night diving mode, the icon is displayed, and the light will flash while the diving log is being recorded. During night diving mode, the light will shine at a lower illumination level (for power saving) than the normal light.
3. Lock the button.

Begin Diving

When the watch detects a water depth deeper than 1.6 meters, it will begin recording a diving log. While recording a log, the digital display shows the current water depth. When the watch detects a water depth shallower than 1.5 meters, it will pause recording the diving log. Log recording is terminated when the diving log recording has been paused for more than 10 minutes. When the watch detects a water depth deeper than 1.6 meters within the next 10 minutes, it will restart dive log recording. Log recording will also be terminated if the diving time exceeds two hours. When the diving timer is on, an alarm will sound when the set diving timer time has expired. After 60 minutes of diving standby (at a water depth shallower than 1.6 meters), the diving mode will automatically terminate.

Press and hold Button B for more than two seconds to terminate diving mode.

CAUTION: Rapid ascent warning display: If the watch detects a rapid ascent during a dive, the digital display will show "SLOW”. An alarm tone will sound during the rapid ascent warning. Even if ascent speed decreases, the alarm tone will continue to sound for the next four seconds.

Diving mode display units

In procedure 4 in "How to set the time and date", the water depth unit and temperature unit can be set.

• Water depth unit: You can choose between meters (m) or feet (ft).
• Temperature unit: You can choose between Celsius (°C) or Fahrenheit (°F).

Check Your Diving Logs

1. Unlock the button.
2. Press Button A to show the diving log on the digital display.
3. Press Button B to select the diving log you want to be displayed. When switching to the diving log display, the total diving time is displayed first. Each press of Button B will display the next log in order from newest to oldest.
4. Press Button A to check log content. Press Button B to change the log content displayed.

How to delete your diving logs

While displaying the log you want to delete, simultaneously press and hold Button B and Button. The watch will display a confirmation prompt for deleting the diving log. Continue to hold Button B and Button, a tone will sound and the log will be deleted. Further continue to hold Button B and Button, another tone will sound and all logs will be deleted. Deleting a diving log does not change the total diving time.

How to reset the total diving time

While displaying the total diving time, simultaneously press and hold Button B and Button. The watch will display a confirmation prompt to reset the total diving time. Continue to hold Button B and Button, a tone will sound and the total diving time will be reset. Resetting the total diving time does not delete any diving logs.

How to use the Stopwatch

The stopwatch can count up to a maximum of 99 hours, 59 minutes, 59 seconds in increments of 1/100 seconds. The stopwatch can count in increments of seconds after 60 minutes has passed. The light will not turn on when the watch is in stopwatch display.

1. Unlock the button.
2. Press Button A to show the stopwatch on the digital display.
3. Press Button B to start the stopwatch. The stopwatch starts or stops when you press Button B. Hold down Button B to reset the stopwatch time. If you press Button A to change the digital display while the stopwatch is functioning, it will continue to function. If the stopwatch exceeds the maximum count time, it will automatically stop and be reset.

How to use the Alarm

Setting the Time Alarm

You can set the alarm to sound every day at a set time. The time alarm will not sound during diving mode.

1. Unlock the crown and button.
2. Press Button A to show the alarm on the digital display.
3. Pull out the crown. "Hour" on the digital display will start flashing.
4. Turn the crown to set the time. Press Button A to switch to adjusting minutes.
5. Push the crown back in to the normal position. The alarm will automatically be turned on.
6. Lock the crown and button.

Setting the Dive Timer

In diving mode, an alarm may be set to sound when the set diving timer time has expired.

1. Unlock the crown and button.
2. Press Button A to show the alarm on the digital display.
3. Press Button B to show the diving time.
4. Pull out the crown. The minutes on the digital display will start flashing.
5. Turn the crown to set the diving timer time. The diving timer time may be set to up to 119 minutes in 1-minute increments.
6. Push the crown back in to the normal position. The diving timer will automatically be turned on.
7. Lock the crown and button.

How to check alarms: Turning the alarm tone on or off: Stopping an activated alarm:

Charging the Battery

How to charge the battery

Expose the dial to light to charge the watch. To ensure optimal performance of the watch, make sure that the watch is kept sufficiently charged at all times. Under the following situations, the energy of the watch is likely to be depleted, resulting in stoppage of the watch:

• The watch is concealed under a sleeve.
• The watch is used or stored under conditions where it cannot be exposed to light for a long time.

Be careful to make sure that the watch does not get hot when it is charging. (The operating temperature range is 0 °C to +50 °C.) When you first start using the watch or starting it after it stopped due to a lack of charge, charge the watch sufficiently using the table on P.54 as a guide. If the time is not restored even after sufficient charging, conduct the procedures in "How to set the time and date" and "How to set the standard hand position".

Guide to charging times

Charge the watch using the times below as a guide.

In the digital display, "BATT" is shown as "bATT". If the time is not restored even after sufficient charging, conduct the procedures in "How to set the time and date" and "How to set the standard hand position".

Energy levels

Two-second hand movement

When the energy level is low, the seconds hand will move every two seconds, which is called "two-second hand movement". If energy is completely depleted after that, the watch stops. If "two-second hand movement" occurs, sufficiently charge the battery. During two-second hand movement, the light will not function, the alarm tone/operation confirmation sound will stop, and diving log recording cannot be started.

Power saving/sleep function

If the dial is not exposed to light and the buttons are not operated for a certain period of time, the power save function activates.

Power save mode

If the dial is not exposed to light and the buttons are not operated for more than two hours, power save mode will be enabled. When the watch is in power save mode, the "PS" symbol will flash.

Sleep mode

If the dial is not exposed to light and the buttons are not operated for about three days, sleep mode will be enabled. When the watch is in sleep mode, the "SL" symbol will flash. During sleep mode, the stopwatch count will be reset and the alarm tone will be turned off.

Turning off the power save/sleep function

Performing one of the following operations will turn off the power save/sleep function:

• Expose the watch to light
• Operate any button
• Pull out or push in the crown

Power Source

The battery used in this watch is a special secondary battery, which is different from ordinary batteries. Unlike an ordinary silver oxide battery, the secondary battery does not require periodic replacement. The capacity or charging efficiency may gradually lower due to long-term use or operating environment. In addition, long-term use may shorten the charge duration due to wear, contamination, lubricant deterioration of mechanical parts, etc. Request repair when the performance lowers.

WARNING: Notes on replacing the secondary battery

• Do not remove the secondary battery from the watch. Replacement of the secondary battery requires professional knowledge and skill. Please ask the retailer from whom the watch was purchased for replacement of the secondary battery.
• Installation of an ordinary silver oxide battery can generate heat that can cause bursting and ignition.

Daily Care

The watch requires good daily care

• Do not wash the watch when its crown is in the extended position.
• Wipe away moisture, sweat or dirt with a soft cloth.
• After soaking the watch in seawater, be sure to wash the watch in clean pure water and wipe it dry carefully. Do not pour running water directly from a faucet onto the watch. Put some water into a bowl first, and then soak the watch in the water to wash it.

Turn the crown from time to time

• In order to prevent corrosion of the crown, turn the crown from time to time.
• The same practice should be applied to a screw down crown.

Press the button once in a while

• Press the button once in a while to prevent corrosion of the button.
• The same applies to the screw-locked buttons.

Performance and Type

The case back shows the caliber and performance of your watch.

• Water resistant performance: Diver's watches feature magnetic resistant performance which is equivalent to or above JIS Class 1.
• Magnetic resistant performance: Please refer to P.64 and P.65.

Lumibrite

If your watch has Lumibrite: Lumibrite is a luminous paint that absorbs the light energy of sunlight and lighting apparatuses in a short time and stores it to emit light in the dark. For example, if exposed to a light of more than 500 lux for approximately 10 minutes, Lumibrite can emit light for 3 to 5 hours. Please note, however, that, as Lumibrite emits the light it stores, the luminance level of the light decreases gradually over time. The duration of the emitted light may also differ slightly depending on such factors as the brightness of the place where the watch is exposed to light and the distance from the light source to the watch.

In general, when coming from a place that is bright to a place that is dark, it takes human eyes some time to adapt to the darkness making it difficult to see objects initially. (Dark adaptation) Lumibrite is luminous paint that stores and emits light, which is harmless to human beings and the environment, containing no toxic materials such as radioactive substances.

Brightness levels

Magnetic Resistant Performance

Affected by nearby magnetism, a watch may temporarily gain or lose time or stop operating. Diver's watches feature magnetic resistant performance which is equivalent to or above JIS Class 1.

• Indication on the case back: No indication
• Condition of use: Keep the watch more than 5 cm away from magnetic products. (JIS level-1 standard)
• Indication on the case back: No indication
• Condition of use: Keep the watch more than 1 cm away from magnetic products. (JIS level-2 standard)

If the watch becomes magnetized and its accuracy deteriorates to an extent exceeding the specified rate under normal use, the watch needs to be demagnetized. In this case, you will be charged for demagnetization and accuracy readjustment even if it happens within the guarantee period.

The reason why a watch is affected by magnetism: The built-in motor is provided with a magnet, which may be influenced by a strong external magnetic field.

Examples of common magnetic products that may affect watches

• Smartphone, cellular phone, tablet terminal (Speaker, magnet of cover)
• AC adapter
• Bag (With magnet buckle)
• AC-powered shaver
• Magnetic cooking device
• Portable radio (Speaker)
• Magnetic necklace
• Magnetic health pillow

Band

The band touches the skin directly and becomes dirty with sweat or dust. Therefore, lack of care may accelerate deterioration of the band or cause skin irritation or stain on the sleeve edge. The watch requires a lot of attention for long usage.

Metallic band

• Moisture, sweat or soil will cause rust even on a stainless steel band if they are left for a long time. Lack of care may result in a rash or cause a yellowish or gold stain on the lower sleeve edge of shirts.
• Wipe off moisture, sweat or soil with a soft cloth as soon as possible.
• To clean the soil around the joint gaps of the band, wipe it out in water and then brush it off with a soft toothbrush. (Protect the watch body from water splashes by wrapping it up in plastic wrap etc.)
• Clean it off with a soft cloth.
• Because some titan bands use pins made of stainless steel, which has outstanding strength, rust may form in the stainless steel parts.
• If rust advances, pins may poke out or drop out, and the watch case may fall off the band, or the clasp may not open.
• If a pin is poking out, personal injury may result. In such a case, refrain from using the watch and request repair.

Polyurethane band

• A polyurethane band is susceptible to discoloration from light, and may be deteriorated by solvent or atmospheric humidity.
• Especially a translucent, white, or pale colored band easily absorbs other colors, resulting in color smears or discoloration.
• Wash out dirt in water and clean it off with a dry cloth. (Protect the watch body from water splashes by wrapping it up in plastic wrap etc.)
• When the band becomes less flexible, have the band replaced with a new one. If you continue to use the band as it is, the band may develop cracks or become brittle over time.

Silicone band

• As for material characteristics, the band is easily dirtied, and may be stained and discolored. Wipe off dirt with a wet cloth or cleaning tissue.
• Unlike bands of other materials, cracks may result in the band being cut. Take care not to damage the band with an edged tool.

Notes on skin irritation and allergy

Skin irritation caused by a band may result from various factors such as allergy to metals or leathers, or skin reactions against friction on dust or the band itself.

Notes on the length of the band

Adjust the band to allow a little clearance with your wrist to ensure proper airflow. When wearing the watch, leave enough room to insert a finger between the band and your wrist.

How to use the diver adjuster

If your watch's metallic band has the Diver Adjuster function, the length of the band can be easily adjusted. It is very useful when you wear the watch over a wet suit or winter clothing.

1. Lift up the flap approximately 90° until it stands upright, and then press the flap down further approximately 20° and lightly hold it.
2. Lightly pull the band on the 6 o'clock side of the watch along the curved line of the band to pull out the slider. Doing this requires only a light force. Take care not to pull the band forcibly. The slider can be pulled out approximately 30 mm. Take care not to pull it out more than this limit.
3. While pressing the push button, lift up the clasp to release the buckle, and place the watch on your wrist.
4. Close the clasp (4-1) first and then, the flap (4-2).
5. Hold both sides of the band to adjust the length of the slider until it fits snugly around your wrist.

How to use the diver extender

If your watch's metallic band has the Diver Extender function, the length of the band can be easily adjusted. It is very useful when you wear the watch over a wet suit or winter clothing.

1. Lift up the flap.
2. While pressing the push button, open the clasp. After opening the clasp, push the flap back to the normal position for safety's sake.
3. Open the two-piece foldover portion of the Diver Extender in the direction of the arrow. Some force is required to open the foldover portion, and it will click when it is opened.
4. Slide the upper cover of the Diver Extender in the direction of the arrow, and then, pull it up to extend the two-piece foldover portion to the full extent.
5. Place the watch on your wrist, and close the clasp (5-1) first and then, the flap (5-2).

After Sales Service

Notes on guarantee and repair

• Contact the retailer from whom the watch was purchased or SEIKO CUSTOMER SERVICE CENTER for repair or overhaul.
• Within the guarantee period, present the certificate of guarantee to receive repair services. Guarantee coverage is provided in the certificate of guarantee. Read carefully and retain it.
• For repair services after the guarantee period has expired, if the functions of the watch can be restored by repair work, we will undertake repair services upon request and payment.

Replacement with functional parts

Please keep in mind that if original parts are not available, they may be replaced with substitutes whose outward appearance may differ from the originals.

Inspection and adjustment by disassembly and cleaning (Overhaul)

Periodic inspection and adjustment by disassembly and cleaning (overhaul) is recommended approximately once every 3 to 4 years in order to maintain optimal performance of the watch for a long time. According to use conditions, the oil retaining condition of your watch mechanical parts may deteriorate, abrasion of the parts may occur due to contamination of oil, which may ultimately lead the watch itself to stop. Furthermore, the digital display may go out due to liquid leaking.

The power transmission gear of the movement of this watch constantly receives force. To ensure that this mechanism works properly all the time, washing parts, changing oil, adjusting accuracy, checking functions and replacing consumable parts on a regular basis are important. The first overhaul after the purchase of your watch is particularly important for preserving long-time use of your watch. According to use conditions, the oil retaining condition of your watch mechanical parts may deteriorate, abrasion of the parts may occur due to contamination of oil, which may ultimately lead the watch itself to stop. As the parts such as gasket may deteriorate, water resistant performance may be impaired due to intrusion of perspiration and moisture.

Please contact the retailer from whom the watch was purchased for inspection and adjustment by disassembly and cleaning (overhaul). For replacement of parts, please specify "SEIKO GENUINE PARTS." When asking for inspection and adjustment by disassembly and cleaning (overhaul), make sure that the gasket and push pin are also replaced with new ones.

When your watch is inspected and adjusted by disassembly and cleaning (overhauled), the movement of your watch may be replaced.

CAUTION: Depending on the environment where a diver's watch is used, its inner parts or movement as well as its case or band may be affected. We recommend that you have your watch overhauled regularly once every 3 or 4 years.

Internal watch light (LED)

The watch uses a technique to uniformly diffuse light from a light emitting diode (LED) with a light guide plate.

Liquid crystal panel

After the liquid crystal panel in this watch has been used for seven years, the contrast will decrease and the numbers will be hard to read. Consult the retailer from whom the watch was purchased for replacement of the liquid crystal panel. A fee will be charged for replacement.

Troubleshooting

How to reset the system

If the watch does not work, the seconds hand does not return to one-second movement even if the battery is sufficiently charged, or the watch operates irregularly, performing a system reset will return the watch to normal.

1. Unlock the crown and button.
2. Pull out the crown.
3. Keep pressing Button A, Button B, and Button C at the same time for more than 2 seconds. The digital display will turn off, and the system will reset. When you let go of the buttons, time and date setup will appear on the digital display. The time and date will be shown as 1/1/2022, Saturday, 12:00:00 am.
4. Set the standard hand position and time/date.

Specifications

The specifications are subject to change without prior notice due to product improvements. Because the H855 makes its calculations based on the specific gravity of seawater (1.025), there will be errors in water depth measurement when used in freshwater.