My radiator is not heating: what should I do?

Snugr regulates temperature using an advanced algorithm.
If a small flame icon is shown for a room/zone, it means that at least one valve in that room is partially open (there is a heating demand).

If your radiator still does not heat up, follow the steps below.

1) Quick checks (before touching the valve)

A. Check the boiler / heating demand

Depending on your setup:

• check that the Snugr boiler control unit is calling for heat and communicating properly (see Settings → Devices),

• and/or check that your thermostat (if you have one) is calling for heat,

• make sure the boiler is on and actually produces hot water for the heating circuit.

B. Check boiler water pressure

A radiator may stay cold if the system water pressure is too low.
Check the boiler pressure gauge and ensure it is within the manufacturer’s recommended range (typically often around 1–2 bar when cold, depending on the system).

C. Check whether radiators need bleeding

Air in the system can prevent radiators from heating properly.

• If the radiator is cold at the top and lukewarm at the bottom, it often indicates trapped air.

• If needed, bleed the radiators (using maintenance mode can help make bleeding easier).

2) If the valve is open but the radiator remains cold

If the valve appears open in Snugr but the radiator does not heat:

1. Confirm the boiler is sending hot water to the circuit (step 1).

2. If other radiators are heating but this one is not, perform this test:

Quick radiator test

• Remove the valve from the radiator (unscrew it, depending on the model).

• Check whether the radiator (or valve body) starts to warm up.

Case 1 — The radiator still does not warm up

This usually indicates an issue with the thermostatic valve body:

• valve body stuck closed,

• valve body faulty,

• or it needs to be freed/unblocked.

Follow:
“My valve shows the ‘mechanical error’ symbol (red spanner): what should I do?”
(This procedure also explains how to check/free the valve pin and then recalibrate.)

Case 2 — The radiator starts to warm up

This means the circuit is fine and the valve was likely stuck closed or not properly initialized.

Re-run the valve initialization/calibration using:
“Mechanical error (red spanner): what should I do?”
(and then run the correct calibration for your valve model).

3) Helpful tip

After any action (bleeding, valve body check, calibration), go to Settings → Devices and check:

• that the valve is communicating, and

• that the last communication time is recent.