nJoin Power Module with Class A GFCI

Part Number: USG-4000
The nJoin is an intuitive Power Module with built-in GFCI for large electric floor heating applications. The nSpire Touch, nSpire Touch Wifi, nHance and nTrust thermostats can be extended with additional nJoin power modules. Output can be increased by 15 A per nJoin module.
This support page provides publications, manuals, specifications, videos, support articles, and common support questions

Common Support Questions (4)

Publications and Manuals (13)

Specifications (15)

Videos (2)

Articles (2)

Related Items (1)

Similar Items (1)

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Common Support Questions


The ground wire in the floor mat must be connected directly to the ground wire of the supply.

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Yes the adaptive function is reset during a factory reset.

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All thermostats are mandated at 42" height for handicap accessibility, most private residences are mounted at 52-60".

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Pressing and holding (2-3 sec) physical power/reset button will turn the unit completely OFF. Same process turns the unit back on.

(nHance and nJoin units will have the button on the front faceplate, nSpire Touch WiFi, nSpire Touch and nTrust will have the button on the right side of the faceplate.)

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Publications and Manuals


Warranty / Certifications

Approvals cULus listed
Ingress Protection (IPxx) Rating IP21
Warranty Limited 3-year warranty and lifetime technical support


Connection 4 wires, double pole
Connection Method Hardwired
Ground Fault Protection GFCI, Class A, 5 mA
Maximum Current 15 A
Maximum Power 1800 W @ 120 V, 3120 W @ 208 V, 3600 W @ 240 V
Supply 120 VAC, 208 VAC, 240 VAC (50/60Hz)

Product Dimensions

Depth 2 in
Installed Depth 0.8125 in
Length 4.688″
Width 2.875″


SKU USG-4000
UPC (GTIN-12) 881308051259



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