Central Heating / Boiler Pressure

Does anyone know of a reliable pressure sensor I could use to monitor my central heating / boiler pressure?

I’ve been looking but can’t find anything. British Gas do an ‘IQ’ system that integrates with WB boilers but are there any standalone sensors around I could add inline somewhere?

Why would you want to monitor pressure ? Surely (unless it is an open system) the boiler has an expansion tank so it will/should maintain a steady pressure on the whole ?


As it happens my system is an unvented (sealed) system, but it’s a fair point, I shouldn’t have to.

It’s an Edwardian house that we’re renovating over time and it’s riddled with bodged old modifications. Since converting the system from vented to unvented as part of a loft conversion I have had a persistent leak meaning I have to refill every couple days.

I recently installed HA and seems to me that it would be pretty simple to track another temp/pressure. I believe I have solved it now as I found an old heating pump buried under the floor that was seeping, but I’d like to set up alerts for any future issues.

Aah - leaks will kill you.

I have a homemade hydronic system also - we have a 5000 litre buffer tank and i use A waterproof ultrasonic sensor to monitor the water level


did you ever find anything? As my combi boiler sometimes needs topping up, and this would be an ideal solution rather than going into the loft to check, or having to go and top it up when the hot water stops through low central heating pressure.

In the absense of a neater solution I’ve set up a cheap pressure sensor on the heating system (on a T piece with isolation valves, taken off a feed pipe to a radiator.), connected up to an ESP32, flashed with ESPHome.

Works well but I haven’t calibrated it properly but I’m really only interested in relative values anyway. At some point I’ll tweak it to match the analogue gauge on the boiler. I’ve had to isolate it for the time being as I was getting a leak from the fitting.

So sorry to reply to such an old thread but could you please let me know which pressure sensor you used? I’m trying to solve exactly the same problem. I can see a fair few pressure sensors but wondering how you connect it to the central heating system?

Do you use a pressure reducing valve and then replace the manual pressure gauge with the sensor or is that crazy talk?



I am still waiting to drain my system to add the reducing tee for the valve, I got one from ali express, it was a 0 to 10 bar one, the order has now gone so i cannot post a link, but I still want to get this installed and find out the math for the voltage to pressure conversion, Oh I also needed an adaptor for car use to get the correct threads.