Instruction/ maintenance manual of the product T8621DA Honeywell
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APPLICATION T8621A,C,D, CHRONOTHERM III FUEL SAVER THERMOSTATS These thermostats provide energy saving control for a 24 Vac heating/cooling system as indicated in Table 1, and are powered direct from the control transformer. As long as thermostat is continuously powered, the thermostat will be compatible with any control system.
2 Fig. 2—Mounting subbase on wall. Fig. 3—Restrict wiring to recessed area surrounding terminals. WIRING All wiring must comply with local electrical codes and ordinances. Disconnect power before wiring to prevent electrical shock or equipment damage.
3 69-0330 — 3 Fig. 5 — T8621C,D 2-stage heat/2-stage cool thermostat with HEAT-AUTO-COOL-OFF system and AUTO-ON fan switching. For T8621C, delete second cooling stage. Fig. 6 — T8621C,D single-stage heat pump thermostats with cooling changeover.
4 Fig. 8 — T8621D 2-stage heat/2-stage cool manual changeover thermostat with auto fan on heat and cool; convertible to auto fan on cool only. HEAT-OFF-COOL system and AUTO-ON fan switching. Fig. 7 — T8621C,D single-stage heat pump thermostats with heating changeover.
5 69-0330 — 3 Fig. 9 — T8621D single-stage manual changeover heat pump thermostat. HEAT-OFF-COOL system and AUTO-ON fan switching. The room air temperature will normally vary slightly from the comfort temperature setting with the cycling of the furnace or air conditioner.
When the batteries are low, the display will flash REPL BAT. The building owner will have 20-30 seconds to install new batteries after removing old batteries from thermostat. After 20-30 seconds, it will be necessary to reprogram. REPL BAT indication will disappear when ther- mostat is mounted back on the subbase.
SYSTEM PRESS LOOK FOR THIS RESPONSE SWITCH THIS KEY KEY POSITION KEY DOWN RELEASED OFF 03 Blank 07 Blank 15 Blank COOL or 15 1st stage cooling, AUTO (with fan and SYSTEM f a n in A UT O) LED on. 15 2nd stage cooling also on. 15 2nd stage cooling off. 15 1st stage cooling, fan and SYSTEM LED off.
SYSTEM FOURTH CLOCK SWITCH DIGIT DEGREES (HRS) POSITION 0 F 12 COOL, AUTO or OFF 1 F 24 COOL, AUTO or OFF 2 F 12 HEAT 3 F 24 HEAT 4 C 12 COOL, AUTO or OFF 5 C 24 COOL, AUTO or OFF 6 C 12 HEAT 7 C 24 HEAT Honeywell Inc. International Sales Offices in all principal cities of the world.
An important point after buying a device Honeywell T8621DA (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Honeywell T8621DA yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Honeywell T8621DA - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Honeywell T8621DA you will learn all the available features of the product, as well as information on its operation. The information that you get Honeywell T8621DA will certainly help you make a decision on the purchase.
If you already are a holder of Honeywell T8621DA, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Honeywell T8621DA.
However, one of the most important roles played by the user manual is to help in solving problems with Honeywell T8621DA. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Honeywell T8621DA along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
