The Efficient Home Forum

Dear everyone,

I am currently facing an issue with my Evohome system, as it is not activating the boiler despite a high heat demand from the RTVs. Below, you will find details about my setup and the troubleshooting steps I have taken:

House Details:
Property Type: 3-bedroom house with 3 heating zones (one zone per bedroom)

Equipment Information:
Evohome Model: THR99C3013
RTV Model: THR091
Valve Type: Danfoss TRV Valve 013G6050
Boiler: Viessman Vitodens 100-W

Zone Configurations (All Zones Identical):
Heating Type: Radiator Valve
Temperature Sensor: Remote Sensor
RF Device Binding: Devices Bound
Window Open Detection: Disabled
Min/Max Setpoint: 5°C/35°C
Local Override: Disabled
Single Room Mode

System Properties:
Internal Sensor Offset: 0
Cycle Rate: 6
Minimum On Time: 1 minute
Fail Safe: Enabled
Advanced Load Scaling: Disabled

I have followed the installation instructions meticulously, connecting the RTVs and Relay Box as directed. Furthermore, I conducted various tests, including:
- Confirming that pressing the test button on the relay box successfully activates the boiler.
- RF TEST Heat Demand indicates Excellent.
- RF Test Zones report Strong/Excellent signal strength.

Despite these efforts, my boiler still fails to respond to the heat demand from the RTVs.

I am seeking guidance on how to further diagnose and resolve this issue. Could this be a problem with a faulty device or potentially an issue with the boiler itself? Any insights or suggestions would be greatly appreciated.

Thank you in advance for your assistance.

Hi,

You could have stuck pins on your radiator valves.
The boiler will not fire until it see's approx 40% open. If your valves are only opening 20% this will not cause the boiler to fire.
To see what is happening with your valves
1. Press settings for more than 3 seconds
2. Press the green tick
3.Press system summary
You should now see the state of each valve %.
This should go up as you increase heat demand and should evan go up to 100% and gradually come down as the target temp is reached.
If your not getting to approx 40% on any valve, remove the head and see if the pin is freely moving up and down.
I've had this and spray on wd40 and give it a wriggle with a pair of pliers (gently) and pushing it up and down. New ones you can push down with your finger, to give you a referance.
You can all so put the hr92 heads on full throw which means they go to 100% at any call for increase of target temp.

Alan

Monca wrote:Dear everyone,

I am currently facing an issue with my Evohome system, as it is not activating the boiler despite a high heat demand from the RTVs. Below, you will find details about my setup and the troubleshooting steps I have taken:

House Details:
Property Type: 3-bedroom house with 3 heating zones (one zone per bedroom)

Equipment Information:
Evohome Model: THR99C3013
RTV Model: THR091
Valve Type: Danfoss TRV Valve 013G6050
Boiler: Viessman Vitodens 100-W

Zone Configurations (All Zones Identical):
Heating Type: Radiator Valve
Temperature Sensor: Remote Sensor
RF Device Binding: Devices Bound
Window Open Detection: Disabled
Min/Max Setpoint: 5°C/35°C
Local Override: Disabled
Single Room Mode

System Properties:
Internal Sensor Offset: 0
Cycle Rate: 6
Minimum On Time: 1 minute
Fail Safe: Enabled
Advanced Load Scaling: Disabled

I have followed the installation instructions meticulously, connecting the RTVs and Relay Box as directed. Furthermore, I conducted various tests, including:
- Confirming that pressing the test button on the relay box successfully activates the boiler.
- RF TEST Heat Demand indicates Excellent.
- RF Test Zones report Strong/Excellent signal strength.

Despite these efforts, my boiler still fails to respond to the heat demand from the RTVs.

I am seeking guidance on how to further diagnose and resolve this issue. Could this be a problem with a faulty device or potentially an issue with the boiler itself? Any insights or suggestions would be greatly appreciated.

Thank you in advance for your assistance.

Best way is to just contact the technical support helpline on 0300 130 1299.