Domain Alerts

Domain: Alerts (0x04)

4.1 Service Reminders Status

COS	Yes
Access	R/W

Service reminders only apply if enabled by installer.

Write semantics

Value	Meaning
0	Clear — clear this reminder if active
1	Set — no effect as “force active”; use for fields you do not want cleared

Layout (10 bytes)

Byte	Field
0	HVAC reminder clear/set
1	Air filter
2	Water panel
3	Dehumidifier (except 8810)
4	Fresh air
5	HVAC time till service 0–100 %
6	Air filter %
7	Water panel %
8	Dehumidifier %
9	Fresh air %

COS: reminder becomes active/inactive; cleared at thermostat; feature uninstalled.

4.2 Alerts Status

COS	Yes
Access	R
Data length	13 bytes

Byte	Field	Values
0	Indoor temperature	0 None, 1 High, 2 Low
1	Indoor RH (except 8810)	0 / 1 High / 2 Low
2–3	Reserved
4	Service reminders alert	0 / 1
5	Heat pump fault	0 / 1
6	Built-in sensor fault	0 / 1
7	Remote sensor fault (except 8810)	0 / 1
8	RH sensor fault (except 8810)	0 / 1
9	OS fault	0 / 1
10	3-wire communication fault (except 8810/8820)	0 / 1
11	8056 wireless outdoor (except 8810/8820)	0 None, 1 ECM error, 2 Wireless error, 3 Low battery
12	Update complete	0 / 1

Default alert limits (adjustable via Alerts Settings (4.3)): High temp 90 °F, Low 45 °F, High RH 65%, Low RH 30%.

4.3 Alerts Settings

COS	Yes — 8840 only, when settings are saved to EEPROM
Access	R/W
Data length	21 bytes (bytes 8–20 reserved)

User-facing alert enables and limit setpoints (app / 8840). Defaults best practices: High temp 90 °F, Low 45 °F, High RH 65%, Low RH 30%.

Fields

Field	Byte	Values
High Indoor Temperature Limit	Byte 0	0: Disabled 1: Enabled 2-255 Reserved Note: This setting controls email and alert messages
High Indoor Temperature Limit Setting	Byte 1	0: 70F or 21C 1: 71F or 21.5C 2: 72F or 22C 3: 73F or 22.5C 4: 74F or 23C 5: 75F or 23.5C 6: 76F or 24C 7: 77F or 24.5C 8: 78F or 25C 9: 79F or 25.5C 10:80F or 26C 11:81F or 26.5C 12:82F or 27C 13:83F or 27.5C 14:84F or 28C 15:85F or 28.5C 16:86F or 29C 17:87F or 29.5C 18:88F or 30C 19:89F or 30.5C 20:90F or 31C 21:91F or 31.5C 22:92F or 32C 23:93F or 32.5C 24:94F or 33C 25:95F or 33.5C 26:96F or 34C 27:97F or 34.5C 28:98F or 35C 29:99F or 35.5C 30:100F or 36C 31:101F or 36.5C 32:102F or 37C 33-255: Reserved Note: This setting controls email and alert messages
Low Indoor Temperature Limit	Byte 2	0: Disabled 1: Enabled 2-255 Reserved Note: This setting controls email and alert messages
Low Indoor Temperature Limit Setting	Byte 3	0: 32F or 0C 1: 33F or 0.5C 2: 34F or 1C 3: 35F or 1.5C 4: 36F or 2C 5: 37F or 2.5C 6: 38F or 3C 7: 39F or 3.5C 8: 40F or 4C 9: 41F or 4.5C 10: 42F or 5C 11: 43F or 5.5C 12: 44F or 6C 13: 45F or 6.5C 14: 46F or 7C 15: 47F or 7.5C 16: 48F or 8C 17: 49F or 8.5C 18: 50F or 9C 19: 51F or 9.5C 20: 52F or 10C 21: 53F or 10.5C 22: 54F or 11C 23: 55F or 11.5C 24: 56F or 12C 25: 57F or 12.5C 26: 58F or 13C 27: 59F or 13.5C 28: 60F or 14C 29: 61F or 14.5C 30: 62F or 15C 31: 63F or 15.5C 32: 64F or 16C 33: 65F or 16.5C 34: 66F or 17C 35: 67F or 17.5C 36: 68F or 18C 37: 69F or 18.5C 38: 70F or 19C 39: 71F or 19.5C 40: 72F or 20C 41: 73F or 20.5C 42: 74F or 21C 43-255: Reserved Note: This setting controls email and alert messages
High Indoor RH Limit (except 8810)	Byte 4	0: Disabled 1: Enabled 2-255 Reserved Note: This setting controls email and alert messages
High Indoor RH Limit Setting (except 8810)	Byte 5	0-49: Reserved 50-90: %RH Set point 91-255: Reserved Note: This setting controls email and alert messages
Low Indoor RH Limit (except 8810)	Byte 6	0: Disabled 1: Enabled 2-255 Reserved Note: This setting controls email and alert messages
Low Indoor RH Limit Setting (except 8810)	Byte 7	0-9: Reserved 10-50: %RH Set Point 51-255: Reserved Note: This setting controls email and alert messages
Reserved	Byte 8-20

High indoor temperature limit setting (Byte 1) — index map

Index	Setting
0	70F or 21C
1	71F or 21.5C
2	72F or 22C
3	73F or 22.5C
4	74F or 23C
5	75F or 23.5C
6	76F or 24C
7	77F or 24.5C
8	78F or 25C
9	79F or 25.5C
10	80F or 26C
11	81F or 26.5C
12	82F or 27C
13	83F or 27.5C
14	84F or 28C
15	85F or 28.5C
16	86F or 29C
17	87F or 29.5C
18	88F or 30C
19	89F or 30.5C
20	90F or 31C
21	91F or 31.5C
22	92F or 32C
23	93F or 32.5C
24	94F or 33C
25	95F or 33.5C
26	96F or 34C
27	97F or 34.5C
28	98F or 35C
29	99F or 35.5C
30	100F or 36C
31	101F or 36.5C

Low indoor temperature limit setting (Byte 3) — index map

Index	Setting
0	32F or 0C
1	33F or 0.5C
2	34F or 1C
3	35F or 1.5C
4	36F or 2C
5	37F or 2.5C
6	38F or 3C
7	39F or 3.5C
8	40F or 4C
9	41F or 4.5C
10	42F or 5C
11	43F or 5.5C
12	44F or 6C
13	45F or 6.5C
14	46F or 7C
15	47F or 7.5C
16	48F or 8C
17	49F or 8.5C
18	50F or 9C
19	51F or 9.5C
20	52F or 10C
21	53F or 10.5C
22	54F or 11C
23	55F or 11.5C
24	56F or 12C
25	57F or 12.5C
26	58F or 13C
27	59F or 13.5C
28	60F or 14C
29	61F or 14.5C
30	62F or 15C
31	63F or 15.5C
32	64F or 16C
33	65F or 16.5C
34	66F or 17C
35	67F or 17.5C
36	68F or 18C
37	69F or 18.5C
38	70F or 19C
39	71F or 19.5C
40	72F or 20C
41	73F or 20.5C

RH limit settings

Field	Byte	Values
High Indoor RH Limit Setting	Byte 5	50–90 = %RH (0–49 reserved)
Low Indoor RH Limit Setting	Byte 7	10–50 = %RH (0–9 reserved)

Bytes 8–20 are reserved.

Guide typos corrected above: the guide prints indices 14/15/34/35 of the low-temperature map with °F unit suffixes on the Celsius values ("46F or 7F"); corrected to °C here. See Guide Errata.