Aprilaire 8800 User Manual

COMMAND SYNTAX
The Model 8800 Communicating thermostat command set includes the Model 8870 Communicating thermostat commands with the addition of a
subset of commands for programmable thermostat functionality and general feature enhancements.
The Host controller has two types of commands: query and assignment. Each of these command types has a specific syntax. Command syntax is
not case sensitive. All commands begin with SN.
A query type command has the following syntax:
SN[#][command]?<CR>
An assignment type command has the following syntax:
SN[#][command]=[value]<CR>
The following table details each component of the command syntax:
Identifier Descriptor Description
SN
Command start First two characters of all commands.
[#]
Address Explicit Address Commands immediately follow SN with the address [#]. The address
range is 1 – 64 and corresponds to the thermostat address. Single-digit addresses may be
sent as a two-digit address by prepending the address with a zero.
Global Address Commands may follow SN with the address zero (0) or the address may be
omitted entirely.
[Command]
Command name See Command Table for list of commands.
?
Query Indicates a query type command.
=
Assignment Indicates an assignment type command. (Always immediately followed by [value]).
[value]
Assignment value Value for assignment type command.
<CR>
Command terminator All commands are terminated with the carriage return character.
NOTE: Following the initial SN[#] syntax, the space character may be used to separate the components of the command for readability and
clarity with the exception of =[value].
HOST COMMAND SYNTAX
A node message is in the form of a command response or an unsolicited message. The node has three message syntaxes which are determined
by the command and if a name has been assigned. All messages are upper case and only use the space character to separate the address
and command and within the assignment value (i.e. after the equals sign). Commands that cannot be interpreted are ignored. There is no error
response message.
For short messages, the following syntax is used:
SN[#] [command]=[value]<CR>
In addition, if a location name is assigned, the following syntax is used:
SN[#][name] [command]=[value]<CR>
For the NAME command response, the following syntax is used:
SN[#] [value]<CR>
NODE MESSAGE SYNTAX
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Aprilaire 8800 Specifications

Thermal Specifications

control temperature range	45º to 99ºF (7º to 32ºC)
display temperature range	32º to 99ºF (0º to 40ºC)
accuracy	± 1ºF (± .5ºC)

Operating Environment

storage temperature	-30º to 140ºF (-34.4º to 60ºC)
operating humidity	5% to 90% relative humidity
operating ambient temperature	32º to 120ºF (0º to 48.9ºC)

Electrical Specifications

voltage AC	24 VAC (18-30 VAC)
maximum load per terminal	1 amp
total maximum load	2.5 amp

Screen

screen size	10.3 sq. in.
backlit	constant low intensity light option
font size	large

Weight and Dimensions

height	4 15/16 inches
width	6 inches
depth	1 5/16 inches