ENGO Heating Controls: An Installer's Guide to Picking the Right One

ENGO build three parallel families of heating control: a plain 868MHz RF and wired range with no app at all, a Wi-Fi range that needs no gateway, and a Zigbee 3.0 range that does. Pick the wrong family and the parts will not talk to each other, so that is the first decision on any ENGO job, before you get anywhere near model numbers.

This guide walks through every control we stock, what each one is actually for, and the handful of details that catch installers out. Every specification here comes from ENGO's own manuals and quick guides.

In this article

• Why installers are fitting ENGO
• Wi-Fi, Zigbee or RF: the first decision
• Room thermostats: which one for which job
• E25 or E40? The difference that catches people out
• Smart TRVs: the ETRV-M30
• Wiring centres for underfloor heating
• Relays and actuators
• Hot water control
• What ENGO does not do
• Pick a control by job type
• FAQ

Why installers are fitting ENGO

ENGO Controls is a Polish brand. Design, specification and quality control are run from their own operation in Poland, with a three-stage inspection process during production, after production and before despatch. They are not connected to any other heating controls brand, whatever you may have heard on site.

Three things make them worth a look if you have only ever fitted the established names:

• A 5 year guarantee as standard across the heating controls range. Not a paid extension, not a registration hoop.
• Direct UK technical support. ENGO staff a UK technical line and a UK sales line, plus a named technical representative covering Great Britain. If a job goes sideways at 3pm on a Friday you are talking to someone who knows the product, not a general enquiries queue.
• A noticeably lower price point than the premium-priced brands most merchants push, for controls doing the same job. On a multi-zone underfloor job the difference across a full set of stats and a wiring centre is the sort of number that decides whether you win the quote.

The trade-off is that the range is broad and the model naming is not obvious. That is what the rest of this guide is for.

Wi-Fi, Zigbee or RF: the first decision

Get this right and everything else follows. ENGO run three separate communication families, and they are not interchangeable.

Two points worth pinning down. First, Zigbee is the more robust choice for whole-house systems precisely because the rules sit in the gateway rather than in the cloud, so a broadband outage does not leave the customer cold. Second, the gateway is not optional on a Zigbee job. Binding a thermostat to a wiring centre or a relay is done through the gateway, so if you are quoting an ENGO Zigbee system, the EGATE-PRO goes on the list at the start, not as an afterthought.

The EGATE-PRO connects by Wi-Fi or by Ethernet, which is the sensible option in a plant room, and it has an external antenna on a lead so you can get the signal out of a metal cabinet or through a concrete floor. Set the Zigbee channel before you pair anything: it cannot be changed once devices are on the network.

Required for any Zigbee system

ENGO EGATE-PRO Zigbee Universal Gateway

Zigbee 3.0 plus Wi-Fi or wired Ethernet, external antenna, USB-C powered. Rules stored on the gateway so they survive a broadband outage.

View product →

Room thermostats: which one for which job

Nearly every ENGO stat gives a volt-free COM/NO contact, which is what a UK combi wants. The exceptions are called out below, and they matter.

The one to read twice is the last row. Despite the similar name, the EONE-16W is a different animal from the EONE-230. It switches a live 230V output at 16A for electric heating mats, where the EONE-230 gives a small volt-free contact for a boiler. They are not interchangeable, and wiring a boiler to a switched live output is not a mistake you want to make twice.

E25 or E40? The difference that catches people out

On paper these look like the same thermostat. Same Zigbee 3.0 and 868MHz combination, same volt-free output, same compatibility with the smart TRV heads, both available mains or battery, both in white or black. The difference is not in the specification table, it is in what the customer can do at the wall.

The E25 cannot hold a schedule without the app. ENGO's own manual describes offline operation as "day mode, without schedule", and the display has no clock and no day-of-week indicator, so there is physically nowhere to show a schedule being edited. All programming happens in ENGO Smart, through the gateway.

The E40 can be programmed on the thermostat itself. Hold OK for three seconds, select Pr, and set four time and temperature intervals per day, with a copy function to repeat a day across the week. The quick guide states plainly that the schedule can be programmed offline. The app is an addition, not a requirement.

In practice that makes the choice fairly simple. Specify the E40 for landlords, holiday lets, elderly customers, anyone who changes phone regularly, and any job where you do not want a callback because someone lost an app login. Specify the E25 where the customer genuinely wants an app-first system and is comfortable with it. If in doubt, the E40 is the safe call, and you will not be back.

The safe multi-zone spec

ENGO E40 Zigbee Programmable Thermostat

Full weekly schedule programmable on the stat or in the app. Mains or battery, white or black.

View the E40 range →

Smart TRVs: the ETRV-M30

The ETRV-M30 is ENGO's smart radiator head, and there is one thing to understand before you quote it: it does not work on its own. Every ETRV must be paired with an E25 or E40 acting as the master controller for that room. There is no TRV-only ENGO system.

What you get once it is paired:

• Up to six heads per thermostat, within the same room.
• No gateway needed for basic operation. The head talks to the stat on 868MHz, so a stat and heads will run a daily cycle offline. The gateway is only needed for app control.
• RA adaptors supplied in the box alongside the standard M30 x 1.5 fitting, so it covers Danfoss RA valve bodies as well as the common thread.
• Open window detection, closing on a sudden 1.5°C drop and reopening after 15 minutes or sooner if the temperature recovers.
• Frost protection, opening automatically below 5°C, plus an anti-stop function that exercises the valve so it does not seize over summer.
• Around a year from a pair of AA cells, with automatic calibration on install.

Still check the valve before you order. Between the M30 x 1.5 thread and the RA adaptors in the box, the head covers the two fittings you meet most often on UK radiators. What the adaptors cannot fix is pin height: it needs to sit 10mm to 15mm proud with the valve fully open. If you are unsure what is on the radiator, send us a photo and we will tell you.

Pairs with E25 or E40

ENGO ETRV-M30 Smart Radiator Head

M30 x 1.5 with Danfoss RA adaptors included. Open window detection, frost protection and anti-stop. Up to six per room thermostat.

View product →

Wiring centres for underfloor heating

Two wiring centres, and the choice is straightforward once you know whether the stats are wired or wireless.

Both boxes build in a three minute delay on the pump and boiler outputs from the moment a zone calls for heat. That is not an arbitrary pause, it is there to let normally closed thermal actuators physically open before the pump starts, so you are not dead-heading against shut ports. The delay is adjustable to 0, 3, 5 or 15 minutes. Both shut the boiler down immediately once the last zone stops calling.

One behaviour worth knowing on the ECB62-ZB: if a bound zone loses communication with its thermostat, that zone switches off after 50 minutes. Good safe behaviour, but it does mean a flat set of batteries eventually shows up as a cold room rather than an alarm, so it is worth telling the customer.

Also: if you have bound a thermostat to the wiring centre, set the schedule on the thermostat only. Setting a second schedule in the module will fight the first.

Relays and actuators

This is where a wrong part number costs you a return trip, so read the ratings carefully.

• EREL-16ZB, Zigbee, 16A volt-free. This is the one for switching a boiler or a pump wirelessly on a Zigbee system. It keeps its stored rules offline and binds to an E25, E40 or EONE.
• EMOD-ZB, Zigbee mini module, 3A switched live. A small module for actuators and light loads, and it doubles as a Zigbee repeater. It is not a boiler relay. If someone reaches for this to switch a boiler because it is the cheaper Zigbee module, that is the wrong part.
• ETR-868 EngoLink, 868MHz, 16A volt-free. A transmitter and receiver pair, supplied already paired, with range quoted up to 300m in open ground. Both units are small enough for a back box. The right answer when you need to get a switching signal across a building with no app and no gateway involved.
• E30NC-230 thermal actuator, 230V, M30 x 1.5, normally closed. Includes the First Open feature, so it sits open out of the box and lets you fill, flush and commission before the wiring is live. 2W each, 4.5mm stroke. ENGO confirm these will also sit on other manufacturers' manifold bars, which is useful on a repair.

Hot water control

The EHW is a Wi-Fi hot water timer with a built-in thermostat, available in white or black, needing no gateway. It takes either a temperature sensor or a volt-free contact on its input, controls to a setpoint between 30°C and 85°C, and gives a volt-free changeover output.

As with any heating control, size the output against the load and follow ENGO's instruction to switch heavy or high inrush loads through a suitably rated contactor with its own overcurrent protection. On a straightforward cylinder or valve application it wires directly.

What ENGO does not do

Worth knowing up front so nobody is disappointed on commissioning day.

• No OpenTherm. Every ENGO thermostat is on/off, either a volt-free dry contact or a switched live. If the customer specifically wants boiler modulation over OpenTherm, this is not the range.
• Alexa and Google only for voice. No Apple HomeKit.
• Heat pumps: stick to the E901 and E901-RF, which are the two ENGO rate for the application. They give a heat pump an on/off demand signal, nothing more, so on a modern MCS install they are unlikely to be the whole control strategy.
• Use the ENGO gateway on Zigbee jobs. These are Zigbee 3.0 devices, but the binding function that ties a thermostat to a wiring centre or relay runs through an ENGO gateway. Pairing them to a third-party Zigbee hub loses the thing that makes the system work.

Pick a control by job type

Frequently asked questions

Related reading: how thermostatic radiator valves work if you are deciding between smart heads and standard TRVs, S Plan vs Y Plan for the system layout the controls have to sit on, and heating controls for the wider range. Manufacturer documentation from ENGO Controls.