Passiv smart thermostat, optimising heat pump controller

The Passive Smart Thermostat is much more than a thermostat. It's an intelligent, optimising heat pump controller designed to improve efficiency, reduce running costs, and deliver better indoor comfort.

By continually optimising heat pump operation, Passiv takes a lot of the work out of setting up and fine-tuning the system. It simplifies installation and commissioning, and provides installers with remote monitoring as standard. 

For homeowners Passiv adjusts the heating to suit the actual building, anticipates changes in weather, and can allow you to take advantage of cheaper electricity tariffs to further reduce running costs.  

A really key advantage for us is that there is a free installer monitoring portal with no subscription fees. 

How does the Passiv smart thermostat work? 

Conventional heating controllers operate by switching the heating on or off according to room temperature. 

The Passiv controller works different. Rather than just telling the heat pump when to run, and when to switch off, it learns how quickly your home warms up and cools down, considers the effect of upcoming weather, and then automatically and smoothly adjusts the heat pump's flow temperature to match the heat needed. 

The aim is to delivery just the right amount of heat, no more, and no less. 

This matters because heat pumps become more cost-effective as their flow temperature decreases. So by doing this the Passiv can help to reduce the running cost. It also results in room temperatures that are smooth and consistent, avoiding the constant fluctuations associated with basic off/on control.     

The Passiv automatically optimises the heat pump's flow temperature, reducing the need for installers to manually configure and fine-tune weather curves. Rather than relying on a single fixed curve Passiv continually adapts to how much heat the property actually needs. The controller communicates directly through an RS485 modbus cable.

Passiv can come with wired or wireless thermostat(s), there is the choice of one or two zone kits. It's possible to commission the system without an app or internet connection.    

There is a free installer dashboard where you can see all your installations, with live and historical operating data, flow and return temperatures, heat output, electrical consumption, homeowner settings and schedules. This really helps with fault investigation and can reduce unnecessary site visits.

The Passiv portal is free to use with no subscription fees. 

Automatic optimisation by the Passiv reduces the need for homeowners to fiddle with the controls, and remote visibility for the installer helps investigate comfort or performance niggles before they become issues. 

As well as helping to achieve lower running costs by keeping flow temperatures sensible, the Passiv can also automatically optimise operation for time-of-use electricity tariffs to further reduce running costs. 

The Passiv delivers far more comfortable and consistent indoor temperatures. It learns how much heat your home actually needs, anticipates changes ahead of time by looking at weather forecasts, and stops the unnecessary overheating and frequent on/off which plague standard heating systems.

The wall-mounted thermostat give easy and understandable access to control indoor temperatures, you can decide when you want the house to be warm, control the hot water (where supported). There is remote access via the Passiv app, and yet it's also possible to operate it all without an internet connection, it carries on working (you do need internet access for app-based features and tariff optimisation).

Passiv works with a wide range of heat pumps AUX, Airwell, Baxi, Carrier, Clivet, Daikin, Ebac, Grant, Haier, Ideal, Kensa, Midea, Mitsubishi Electric, Panasonic, Riello, Samsung, Worcester Bosch.
(Daikin, Mitsubishi and Panasonic require an additional modbus interface).

You can check the manufacturer and model against Passiv's compatability list - for some brands the features available may vary.  

As mentioned there are one and two-zone kits, with the choice of a wired or wireless thermostat. In the kit you get a Passiv Hub, Programmer, thermostat(s), Ethernet cable and mounting accessories. The Hub lets you connect the system to the internet, the programmer gives access to the control of heating and hot water, the thermostat(s) are mounted in the actual room. You get a thermostat for each zone, so with the two-zone kits you get two. You will likely need some extra RS485 cabling.

Thermostats should be positioned in rooms representative of the heating zone, away from draughts, direct sunlight and other influences that could distort temperature readings. An entrance hallway with frequent cold draughts, for example, may be a poor location.