Z-Wave Boiler Programmer?

I’ve already got a Nest 2nd Gen thermostat, and I know the 3rd gen can control you hot water, however I’m not going to pay £150 for a new Nest, plus the installation cost for a rewire when the hot water is currently controlled just fine by my boiler.

Basically Im after a Z-Wave programmer where I can set the heating to be permanently on (thus being controlled from the Nest) but where I can schedule the hot water to one using an app or SmartThings.

Right now, I’ve simply got a timer that turns it on/off, the old fashion way, but lets be honest, it’s not ideal, heres why.

Currently timer say for the hot water to come on at 05:00 - 06:30 and then 18:00 - 19:30. If we go away for the night and nobody is home, then theres not much point in having the water come on. Yes, there are situations where we might come home later, but theres no point in having the water come on at and then us having to give it a boost when we get in. Might as well just set it to come on later from my phone.

So to confirm, im not after a new thermostat, just a programmer

Is this an electrical boiler? If so, what specs? Does it plug in?

If it’s a gas boiler, I would not use a zwave or zigbee home automation device to control it, unless specifically designed for that purpose.

If it’s electric, it’s easy. You just control the power to it. If it’s plugged in, that’s one option. If not, you could probably use an in-line relay.

Nope, its a gas boiler.

I’ve currently got my Nest as the thermostat and one of these programmers:

In ‘the old days’, you would have set a timer for your heating to come on. If the temperature in your house was below the thermostat at those times, your boiler would have come on.
In the IoT days, your programmer is set to always be on, and your thermostat tells the boiler when to come on. Works in exactly the same way, but your smart thermostat can run off automated schedules etc.

What the 3rd Gen Nest does is taps into the thermostat on the hot water tank so that it enables the same functionality as the above. Right now, my hot water only comes on when I tell it too without any automated scheduling.

Lets be honest, nobody changes the temp of their hot water tank on a regular basis, so a Z-Wave enabled programmer would solve the problem quite easily. I’m not after some hack, im after a proper z-wave enabled programmer, designed for that purpose

There is this:

which would have been ideal without the thermostat, but the kicker is Important:

This timer cannot be controlled by other Z-Wave devices except the Secure Wall Thermostat. It cannot be included into a Z-Wave network that is controlled by a Z-Wave controller such as VERA or Home Center 2.

That caveat is for the thermostat which expects to be a primary controller. You can also buy just the receiver unit from Vesternet, and they say it works fine with Vera, so I would expect you to have a good chance of getting it to work with SmartThings. I would ask Vesternet technical support to be sure, they’re usually very good.

I saw that, but my problem there is:

  • there doesn’t appear to be an easy on/off mechanism for the heating
  • with SmartThings having the reliability that it does, what happens if they have a failure, or my Internet goes down. I’ve got no way of setting the schedules manually.

Good idea, but the implementation isn’t what it needs to be for my purpose

I am no expert on the HA devices available. But, wudn’t this help alongside a ST connected outlet?

I was thinking about doing this setup myself. Just not in a hurry.

I think you are missing the most basic thing. If these units are to increase home comfort and save money fuel and the planet then the first thing is put as much insulation around your hot tank as possible.
That way the water will stay at the temp for easy a day let alone hours unless you run it off. I found using the reflective multi foil insulation such as SF40 very good rather than relying in the few centimeters of foam that the hot water tanks come with.
good luck

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