Reliably setting various trv set points

Just an update - works to perfection. The wife is actually beaming. Previously she hated it, but liked the cost savings.

Edit. Pics. Inside that double back box, there's a nodemcu connected to a 3v relay controlling when the ac power is able to flow to the thermal actuator. All looks quite slick, to be honest. Also purchased a few momentary buttons. Plan is to have a button on the box to activate a 20 min boost, which is currently only done via software. A light too to show when the valve is active.

To be even more mother-in-law friendly, I'm going to build a control box, and mount one per floor in the hallway. Labelled with a few LEDs with boosts for each room via switches. Probably have buttons for enabling and disabling schedules for the rooms too. It's all quite simple when you break it down.

Really good to know, thank you.
I’ll have to work on the box design and if that can be wide approved.
I’m currently having to check the Popp trvs manually as they randomly go into ES alarm and don’t respond. Plus for the set point, i have to be a webCoRE check every 15 mins to ensure the set point has applied. It works but is clunky and effectively means there is no local control.

I think I’ve answered myself, motorised valve is the future.

Hell yes. Interestingly though, webcore does run local on hubitat.

I use one Piston per room. Which runs every few mins, with desired setpoints etc. Works really well.

How funny, I was just looking at how I might do this, to make room heating possible, as opposed to whole house, and you're building it already!

How do you have that setup linking with Heatmiser? (EDIT, realise you arent using a Heatmiser Thermostat, ignore this part) Are you basically using small Sonoff devices to control the thermal actuators in your white box?

How do you ensure the boiler doesnt turn on when all TRVs are shut? Ive read that it can rapidly cause the boiler pump to fail.... Especially as the valves can take 2-3 minutes to open

Attached is how I've been playing with the heating set points, giving a profile through the day depending on room usage, a variance if we're out and if sensors are open and closed..

Also and example of the boiler switch, effectively meaning that the boiler isn't firing on and off for too short a period. My system does have a pressure release and some radiators not on trvs.

@cjcharles

Yup, not sonoff, nodemcu's. But same diff I guess.

My boiler has a bypass, very inexpensive, so no issue. It's on my to do list to add a timer though to only pump 2 mins after opening, and to shut off 2 mins before closing just to save a bit of energy. It is good practice to have one single rad hooked up as 'always on', generally the bathroom. I didnt want that, and had the bypass fitted instead.

I have another Piston which fires the boiler up or switches it off depending on what's turned on or off. Pretty simple.

=)

Yes thats true, a bypass helps, but if the loop is too small then the boiler gets horrifically confused due to the temperature oscillations in the pipe!

I saw you mentioned NodeMCUs, but thought you meant something else, as they dont come with the mains voltage conversion or a relay, hence I guess you've added a little USB power supply and 1CH relay board inside your box? Only other thing to add would be a small temperature probe so you can get a room temp reading aswell!

I have seperate room temp probes, placed in a better location, connected to the node. I power each floors nodes by a seperate 12v psu per floor. And yes, 1 ch relay.

The bypass is the furthest distance away from the boiler in a 3 story house so the effects are fine I believe. As I said, a delay tuner needs to be incorporates for full kick-■■■ implementation, imo. But for now, I'm not worried. Been working this way for a year, in various forms. =)

Gotcha, and what temp probe are you using?
Thanks!

Dht22. Spot on. Konnected firmware. Updates approx every 3 mins

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Thanks! And why Konnected firmware rather than Tasmota / Sonoff / DIY? So many questions as I play with some new smart home ideas!!

started when I still had smartthings, just before they started really shagging the system.

In this thread...

... which I started back on July 3rd, I wanted to know if there was a decent way of connecting dumb door sensors etc as opposed to buying a stack of 20-odd-quid zwave ones (which I didn't want to do).

This guy...

... waded in with so much advice/info, I was blown away. So much help! And ditto for Nate....

...who is the developer of konnected.

Long story short, I was trying to future-proof. Didn't fancy doing it all over again when samsung completely screwed ST. And it turned out that classic konnected supported DS18b20's - the main part of my CH/Hottub solution. But unfortunately the new ST app didn't - oh no! =p

It came into conversation that hubitat had it's own version of konnected, which happily supported absolutely everything. And wow.... local too?

So after a quick play and lots of advice, I decided to take a crack at hooking up some 12v PIRs, DHT22's (might was well have a go with humidity too, eh?), and leaving my DS18b20's for external/tub use. Great timing, because after I started getting to grips with it all, samsung completely screwed up ST, so I thought "fcuk it", bought a hubitat at the end of july, and began migration.

Why not tasmota etc?

I wanted something easily replaceable, easy to source, cheap components. The cost breakdowns for this system is something like:

nodemcu................. £2.50
3v relay................... £4
all sorts of sensors, rain, leak, humidity, temp, motion, contact, switches etc.......... pennies.

(example, i use a dedicated nodemcu for my garage door opener. And another with a cheap-■■■ mometary switch just to add control for our bedroom's salt lamp on the opposite side of the room. The possibilities are literally endless).

I was initially a little dubious of wifi boards and response times. But I was assured it was fine. A quick go under ST showed adequate performance. Under hubitat...? Phenominal.

So here we are.

I could not be happier. Ripped it all apart and started afresh. Works faultlessly, not something I could ever achieve with ST/Fibaros.

Anything else you need, feel free. I'm incredibly happy with the entire system. I would prefer a smartapp to be able to edit schedules (instead of webcore), but that's not the end of the world. We always have the 'boosts' to give the CH a 30 min blast if needs be, schedules don't really need to be touched. And it's easy enough to not bother heating if the alarm is set. =)

-=edit=-

for completeness, here's that 2nd piston I was on about.

-=/edit=-

Probably obvious but doesn't this method need mains power to each radiator?
Would be very difficult for me to do which is a shame
also can't find 10 for 58 quid or anything like it - must have been an offer.

Mike

Yup, needs mains power. I run a single 2 amp plug throughout the house, my layout markes it pretty simple via trunking.

Possibly was an offer. This is what shows up as my past orders now... Its the actual one I used dut to the red indicator (thr cheaper one didn't have one).

System is working absolutely beautifully.

Thanks :slightly_smiling_face:

Not a issue for me but what exactly have you got the actuator connected to? Got any photos?

@BorrisTheCat

No photos as such, but I have a standard electrical double backbox mounted near the rads containing the nodemcu, few wires and the 3v relay.

Here's the actual relay I bought

Here's a pic

So. (obviously?) the node is connected to the relay. Relay only switches on when the node tells it to, and thus only allows the actuator to receive power when the node has powered the relay.

Project isn't entirely finished - I prefer to have my smart stuff operating as smart and also appear as dumb. So I still want to build a control box for the hallways so we can see at a glance what's going on, have switches to fire up the boosts, enable the schedules etc.

Now I've discovered WLEDS, it'll be cool to have one led which will be different colours depending on whether something is on, off, boosted, too hot, too cold etc.

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So just trying to work out best way to do this if you had a blank canvas. What cabling is needed from where too where and how many core's ?

Obviously the actuator is only live, neutral and earth. I mean the smart side.

I'm the same.

I use 2 cables. Both 2 core. The actuator only has a live and neutral and I run this off a 2amp fused plug. The 2nd cable is +/- from a dc psu.

I also already had some 6 core (I think) alarm cable which I used to run from the node to my temp sensors which need 3 (+/-/data). The intention is to (on some) add in a door contact sensor and motion, all on the same node.

The particularly cool bit (for me) is the webcore and the dash.

Here's my work in progress.

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