Reliably setting various trv set points

Very new to HE and still learning.
I have 8 (currently, due to expand) zwave trvs. They seem to working ok with HE and regularly updating.
I have a rule engine that checks the thermostat state (idle/heating) for these trvs and switches the boiler on or off depending on demand. All good.

My issue is with setting the trv set points reliably. What should I use?
With my ST set up I used webCoRE for each of them with success. Some are simple, if home and time is between x and y, then set to zdegc. Others like the kitchen are more complicated, varying with time of day, motion, and door sensors.
I wanted to get away from the webCoRE internet dependency, not for any reliability issues....

I have tried thermostat scheduler, but checking the dashboard and devices, set points are not reliably being applied. Kids bedroom is set cold, another is set too hot.
Rule engine seems messy, needing a new rule for each time of the day or motion trigger or location mode. Am I wrong?

I have a constant wife justification to make and at the moment erratic temps are not helping my cause.
Thank you.

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Not quite answering your question, but I'm porting my crap from ST to here. My trvs are currently unsupported in hubitat and to be honest, have always been a bit flakey. Decided to try an alternative approach.

Here's a text I just sent an hour ago to my plumber mate...

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Bet this hasn't exactly been keeping you awake at night, but I knew there was a simple solution.

Specifically designed for cutting off liquid flow at a manifold etc. Screws directly onto an m30 thread (I. E. Onto an existing standard TRV body).

Apply a voltage, actuator moves one way. Remove the voltage, actuator returns to start position.

They're used for underfloor heating, most commonly.

"2 wire thermal actuator".

Pack of 10 for 58 quid on amazon. Or buy a single from a merchant for 12 quid.

It's essentially an electronic trv, no smart involved, purely a dumb device.

Completely agree that my ideas for pretty much everything can sound a bit mental, but they're generally based on something solid.

Doddle =p

==============

I've currently ordered 1 brand at 12 quid and another for 8. The 8 quid one is yet to arrive (Thurs). If it works (the 12 quid one is fine), then I'm buying the 10 set for 58 quid.

I'm sick of the complexities of setpoints etc. I'll adjust my webcore script to turn on/off when needed.

I use external temp sensors and different 'desired temps' depending on time of day or whether I'm home or away, if the heating schedule for that particular room is enabled or not etc.

Would be happy to share the code if you so wish, but it is webcore. But that runs local.

Love it. Great idea and so much simpler. For me it might make it easier for zigbee trvs too, using a zigbee switch.
Let me know how it goes.
Cheers.

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Thankfully, amazon have actually agreed to let me send back my patchy drayton wiser TRV's I purchased in november (!).

2 wire actuators, here I come ! =p

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=-