Overview

Overview

Where a sophisticated Building Management System is installed at great expense by an expert systems programmer there is an 'efficiency gap' in the control strategies of such systems. Boilers, in principle, need to provide the correct amount of heat energy to balance building heat losses and gains under given set point and weather conditions.

What is not understood is that 'state of the art' installed building controls - even those produced and sometimes maintained by prominent global suppliers such as Siemens, Honeywell (Trend) and Johnson - are falling short of the ability to dynamically balance building heat gains and losses through their currently embedded or programmed control strategies.

The two main contributors to heat wastage in buildings, whether poorly or well controlled, are:

Boiler set-point temperatures are nearly always unnecessarily high even if compensated for demand.

Control decisions to change boiler temperatures, sequencing or the mixing of primary temperatures to achieve lower secondary temperatures are made as a result of inside and outside temperature differences and not building heat losses and gains. Every building has its own heat transfer profile and heat "inflows" have to be dynamically reconciled with "outflows" for good energy control. This individual balancing is needed to prevent buildings being over-heated.

How do we fill this "gap" in building control intelligence?

Existing control systems, at best, make use of inside and outside sensor temperature networking to drive controls for more comfort. Correctly programmed Building Management Systems and even Weather Compensation Controllers, in conjunction with Constant and Variable Temperature controlled circuit controls, generally make good comfort control decisions. Such decisions in themselves, however, are not the best from a system efficiency standpoint. Although our systems observe the set points and demands of comfort controls it imposes a higher order of intelligence in terms of efficient and dynamic temperature control, step and sequence of boilers. MK Enermatic intelligence is based on continuous development of a heat loss / heat gain profile as the building is affected by internal and external conditions over a 24 hour cycle.

It also self-determines the point at which profiling is converted to boiler control and sequencing to provide the lowest primary temperatures to meet comfort demand set by the other building/comfort controls. This results in no excess heat or " standing losses" being absorbed by heating system equipment or the building fabric or by the space itself due to overshoot of set points. Significant amounts of fuel are saved with this practice. As time passes, the system accumulates its daily data, thus adding a refinement to its learning about the building's heat loss/gain characteristics and tuning itself ever closer to the exact heating needs. No heat wastage and no building overheating.

The process of prediction, analysis, control and management of boilers is completely automatic and self-learning once it is commissioned. There are no user controls needed except for an "override" switch for use during normal maintenance schedules.