Why we like electronic
It Solves Real Problems
The following problems all cause considerable problems in the real world for the efficient operation of an HIU and the network it is connected to. Electronic controls allow us to fix them all:
- Poorly balanced radiators normally result in elevated return temperatures. Electronic control allows us to limit return temperatures so a poorly balanced system will not impact on plant efficiency.
- Hot corridors. Often caused by poor keep-warm modes. Electronic control lets us accurately set the way keep-warm works, and enable one to again set the maximum temperatures fed back to plant. We can also time when the keep-warm takes place, or even turn it off.
- Dropping primary temperatures to an HIU usually causes them to struggle and draw more heat, resulting in elevated return temperatures. Again, a return temperature limit solves this problem, as well as the feature to alter target temperatures to what is achievable depending on available primary temperatures,
- Setting DHW temperatures over 55C for Legionella safety causing inefficiency. The DHW temperature can be set lower on an Electronic HIU, and if you are worried about Legionella there is a Legionella Function that raises temperature for a short period overnight, so you can enjoy high efficiencies, as well as mitigating perceived risks.
More than one function per control valve
Flow related functions performed on a primary circuit:
- Target temperature control
- Return temperature limitation
- Differential pressure regulation
- Trickle flow
With mechanical systems, each function requires a separate valve, or components within a valve set.
Electronic systems allow all these functions to be applied using a single control valve, with the following advantages over mechanical systems:
- Less components
- lower cost
- less heat loss
- improved reliability
- only one type of spare valve required for servicing
- Virtually unlimited number of functions at no extra cost - just extra lines of code
- Parameters can be software defined and user adjusted to affect operation
Speed control over pumps
Electronic systems allow direct control over pump speeds, often avoiding the need for valves entirely.
An electronic system is time aware.
It can adjust its mode of operation at different times of the day, or even adapt its timing. This adds functionality such as:
- Sterilisation at regular intervals, enabling lower temperature supply policies to be used without fear
- Central heating timing
- Optimum start
- Pump exercise
- Timed keep-warm
Data and Memory
An electronic system can log sensor and performance data for future analysis.
By no means a necessity, when everything works perfectly, but when it doesn't, or to be sure it is, then this data is invaluable.
Five years ago, when we had a telephone call of a problem on a site and we need to attend, we would need to send an engineer. Today, we can simply login to the system and tell them to check their secondary return pump as its failed (for example). We can tell them when it failed, and how it failed.
In a commercial plant-room something as simple as a pump failure can take up significant resource, just to diagnose, traditionally. First there is the process of failure, with the resulting loss of services (hot water for example). The discomfort this causes results in complaints to managing agents, landlords, and plumbers, that can be followed by an entourage of personnel poking around in properties and plant rooms until someone suitable qualified or informed works out the problem.
With an electronic system, both the user, equipment manufacturer and the appointed service engineer can receive emails and text messages immediately upon failure, and they can even be notified in advance of the failure if the pump performance is been monitored.
With electronics now built in as standard to HIUs, the same functionality can be applied on a domestic level as well as in plant.
- PID and more complicated control loops
- Valve pulsing
- Weather compensation
- Remote setpoint adjustment
- Component analysis and failure prediction
- Modular (range rating) systems
- Metering and billing
- Networked hot water priority
Heat network analysis
Pressure and temperature mapping an entire heat network live, provides remarkable levels of information that allow problems to be easily spotted diagnosed.
The most common been blockages in pipework, blocked strainers, open flushing by-passes, and undersized pipework. The data simply cuts through all the arguing about whats wrong, where, who's paying to fix it, and can't we just try this, with the facts.
Joined up thinking...
Boiler plants communicating with distributed storage to maximise the use of cheaper heat, and allow distribution pipework to cool or turn off.
HIUs working together to manage loads, improving capacity of the network.
Central heating and hot water control on a common user interface with energy supply, billing and maintenance functions.