Sinope Thermostat Error Codes: E1, OL, HH, LL and GFCI

Reset the circuit breaker

Sinope’s breaker reset, in its own steps: find the circuit breaker connected to the unit, switch it off, wait about 30 seconds and switch it back on. It is Sinope’s listed solution for E1, E2, E3, E9, E11, E12, E15, E16, E17, E18, E19, E20, E28, GFCI, HH, HHF, LL, LLF, OL, OL1 and OL2, and for E7 together with a reset of the GT125 gateway’s power.

If the same code comes back, read its row in the table above before you reset again. Sinope’s technical support line is 1-855-741-7701.

HH, LL, LLF or HHF: the room is outside its range

Sinope says to make sure the thermostat’s operating temperature is between 32°F and 122°F (0°C and 50°C). HH means the room is above its reading range, LL and LLF that it is below, and HHF that the floor sensor reads above the range. Once the room is back inside that range, reset the breaker.

OL, OL1, OL2 or E19: too much load

OL and OL1 mean the overload protection has switched on because the connected load is too high. OL2 adds a second cause, an internal temperature that is too high, and E19 means the internal temperature passed the device’s limit. Sinope says the load must be equal to or less than the thermostat’s limit:

To add up the load, Sinope says to read the watts on each heater’s label. If a baseboard’s label cannot be read, its rule is 250 watts per foot of baseboard, valid only on 240 volts: a 6 foot baseboard is 1500 W at 240 V. For OL2 and E19, also check that no outside heat source is warming the thermostat. A load over the limit needs a thermostat rated for the total, and on a line voltage circuit that change is an electrician’s job.

E1F, E2F, GFCI or E17: the heated floor

E1F means the internal temperature sensor has reading errors, or the thermostat is set to floor control mode with no floor sensor connected. E2F means the floor sensor has reading errors. Sinope’s steps: check the floor sensor is correctly installed and not faulty, which means the thermostat’s wiring, so have your electrician check it with the breaker off. If the sensor is faulty, have it replaced or change the control mode to ambient; with no floor sensor at all, change it to ambient.

GFCI means the thermostat sees a short circuit on the load connection of its relay. Reset the breaker, then press the reset button on the right side of the thermostat. E17 means the GFCI self-test failed: reset the breaker. If either persists, Sinope says to have your installer or a certified electrician check the floor heating installation.

E4 to E8 or E13: the GT125 gateway

For E4 and E7, Sinope says to check that the gateway’s RF light is green and steadily on, and that the thermostat is about 30 feet from the nearest GT125 gateway or Mi-Wi device. Then, for E4, reset the RF connection and reconnect it; for E7, reset the breaker, reset the GT125’s power and try to connect again.

E6 means the thermostat sees a GT125 gateway but no open connectivity session, and E8 that it has never been connected to a GT125: for both, press the RF button on the GT125 once, then add the thermostat. E5 means the thermostat sees more than one gateway with an open session. If a close neighbor opened one at the same time, Sinope says to wait a few minutes before reconnecting. E13 means it lost the gateway: reset the RF connection, then open a session, reconnect and close the session. Sinope says this does not erase what the thermostat has saved.

A blank or blinking screen with no code

Sinope’s order: first the circuit breaker, because a tripped breaker cuts power to the thermostat and the screen goes dark. Then make sure nothing is blocking the heater: its thermal protection can cut power to the baseboard and thermostat. Sinope adds that some baseboards distribute heat less effectively if they are not firmly against the wall.

Next, the capacity: depending on the heater’s power, the size of the room and the outdoor temperature, it may run continuously without reaching the set temperature, which can overheat it and trip that protection. Sinope also suggests, if possible, swapping in a thermostat that works to see whether the fault follows it; that means rewiring, so it is one for your electrician. With the breaker working, nothing blocking the heater and the problem still there, it says to contact an electrician.

E25, E26 or E28: call Sinope

E25 is a TLS certificate error and E26 a HomeKit token error, and for both Sinope says the device must be replaced. E28 means the thermostat has detected a problem with the power supply: reset the breaker, and if it persists, contact technical support. Sinope’s line is 1-855-741-7701, or use the web form on its support site.