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Equipment Interface Module (for single and multistage heat pump)

Price: $88.78
Excl. Shipping
SKU: THE8635B1004
(See Product Details Below for Manufacturers Part Numbers)
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Equipment Interface Module (for single and multistage heat pump)


W8635A,W8635B Equipment Interface Module provides 24 Vac control of single- or multi-stage HVAC equipment when used with a T8635L Microelectronic Communicating Thermostat. The W8635A works with up to 2 heat/2 cool conventional applications. The W8635B works with up to 2 heat/1 cool heat pump applications.


W8635A controls conventional gas, oil or electric heat systems.

W8635B controls single-stage or multi-stage heat pumps.

Uses Honeywell EnviraCom
• communications protocol

Product Specifications

Application Controls single-stage or multi-stage heat pumps

Network Zoning Yes

Number of Zones Single- or Multi-Zone

Heat Pump Compatible Yes
Compatible with Discharge Air Temperature Yes

Color Gray

Individual Zone Fan Control Yes

Terminal Designations 1, 2, 3, C, R, Rh, L, G, W1,Y1, Aux, E, O, B

Dimensions (in.) 4 3/4 in. high x 4 3/16 in. wide x 1 1/4 in. deep

Dimensions (mm) 121 mm high x 107 mm wide x 32 mm deep

Mounting No. 6 screw and wall anchors supplied in bag assembly

Operating Humidity Range (% RH) 5 to 90% RH, non-condensing

Stages Up to 2 Heat/1Cool

LEDs Yes

Electrical Ratings 20 to 30 Vac

Frequency 60 Hz;50 Hz

Switch Positions (System) HEAT-OFF-COOL-AUTO-EM. HT.

Ambient Temperature Range (F) -40 F to +150 F

Ambient Temperature Range (C) -40 C to +66 C

Replaces Part Numbers: CARW8635B1004

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I would like to thank you for your hard work in getting us our part in a timely fashion. You were very helpful and you understood the severity of the situation and did a wonderful job in getting the part to us. Thanks again and please share this with your boss! You were outstanding!"
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