[OpenTRV-dev] TRV control - my problem, and musings so far

[Thomas Hood]

On Tue, Apr 2, 2013 at 11:53 AM, Kevin Wood <EMAIL ADDRESS HIDDEN> wrote:
> 4) Integration and control strategy
>
> I'd mused that each "zone" could transmit a figure each time it "woke",
> perhaps based on a comparison between current temperature and set point,
> indicating the local level of "desperation" for heat. The programmer would
> sum these and use it as a criteria to determine if it's worth lighting the
> boiler. In this way, a single zone dropping a fraction below target while
> the rest are happy wouldn't result in a potentially wasteful short cycle
> of the boiler, yet a number of zones in such a state would, as would one
> zone that's well below target or where the set point has recently been
> increased. Each zone would receive a response from the programmer,
> indicating if heat is being supplied, and also if a pump overrun condition
> exists, allowing zones to open and take "waste heat" based on some
> criteria.

Writing software to control the boiler(s) optimally and safely based
on information provided by other system components will certainly be
one of the biggest challenges.

Among the commercial systems that I have looked into only Honeywell
Evohome and Danfoss Living Connect dare to control the boiler and only
Honeywell can control a modulating OpenTherm boiler. Reading forums
related to these systems I didn't get the impression that the software
in those systems has been well tuned yet.
-- 
Thomas