Need a smart thermostat for a dumb house

April 25, 2018 10:59 AM

My house has an old forced-hot-water heating system with radiators. It is dumb and slow. Which easy-to-program thermostat should we get?

The heating system has just one zone. It takes a long time for the radiators to heat up and then a long time for them to cool back down. Different radiators put out different amounts of heat, so some rooms can be too hot and others can be too cold.

We don't have central AC. We don't have any smart appliances.

We understand that a thermostat is not going to fix these problems. The heating system is what it is. But we'd still like to upgrade our thermostat. Specifically, we'd like to be able to

1. Program a daily schedule.
2. Override that program temporarily if the house feels too cold or too hot.
3. Override the program for a few days when we are going away, to save on heating costs and emissions.

We'd like to be able to do this without having to push unresponsive hard plastic buttons hundreds of times while reading a low resolution LCD screen to navigate through days days of the week and times of day.

We don't need to talk to our thermostat and we don't particularly want our thermostat to send our heating information to Cambridge Analytica.

When I look at reviews of smart thermostats, they all seem to focus on fancy heating systems with multiple zones, heat + AC, ventilation, and remote access via apps. I don't really care about any of that.

I just want a thermostat that is easy to use and program for our dumbass old forced hot water radiators.

posted by Winnie the Proust to Home & Garden (12 answers total)

I can't give you a specific recommendation, but you might want to consider one of the ones with remote sensors so you can program it to prioritize making specific rooms the appropriate temperature for the times you use them most.
posted by Candleman at 11:22 AM on April 25, 2018

but you might want to consider one of the ones with remote sensors so you can program it to prioritize making specific rooms the appropriate temperature for the times you use them most.

It is impossible to do this with hot water radiators.


Our house is much like yours - hot water radiators that heat our three story 1910 home all in once zone. We purchased this touchscreen thermostat based on Amazon reviews. It does everything we want it to do and nothing weird. Amazon reviews trend toward "hard to program" but we did not find this to be the case. We have it programmed to change the temp 4-6 times a day, over 7 days, and it does have a vacation mode.

You might do better looking for "touchscreen thermostat" vs. "smart"
posted by anastasiav at 11:31 AM on April 25, 2018 [3 favorites]

2nd Candleman to say that smart thermostats with remote sensors do exist like the ecobee. I will add that most if not all of the smart thermostats on the market will learn over time how responsive your heating system is and will take that into consideration on when to turn itself on and off.

I think however that you are likely going to have to make a decision about what side of the feature divide you want to be on. You can still buy cheap programmable thermostats that have no internet or apps capabilities but the paradigm of using/programming them is stuck right of 1995 fever dream where you are trying to setup a recording session on a VCR.

All the innovation (and the ease of use/programming) are on the smart thermostats which offload a lot of complex UI stuff to a phone app or a website which then necessitates having internet connectivity on the thermostat. While I think I can do all the programming I need on my ecobee's little screen, the app & website are light years easier.
posted by mmascolino at 11:32 AM on April 25, 2018

I went through three of the damn new electronic ones before I put back the original mercury switch in my house. Batteries die, sometimes the electronic ones heat or cool for seemingly no reason, one needed to be completely reset every time the batteries died (PITA 15 minute process), adjusting the +/- sensitivity isn't even an option on some, toddlers can reprogram it by randomly hitting buttons, wifi ones can be hacked, what happens if the batteries die while you are away on vacation, waking up hot because you forgot that you hit override, etc. etc.

The old school ones are dead simple and sometimes more adjustable. It was like removing one of the hassles in my life when I put the old one back on! So think long and hard about how much you need it.
posted by Patapsco Mike at 11:43 AM on April 25, 2018

We have the same type of heat as you do and a basic Honeywell programmable thermostat which works really well. It's programmed to be warm in the morning and evening and cooler during the day and overnight. It has a one-touch hold for vacations and such, just set the temp and press hold. Then when you get home just press hold again and it resumes the programmed routine. I also sometimes occasionally override the temp in the evenings to make it warmer, and it just stays at that temp until the next programmed phase (evening cooldown) so I never have to undo the override, it happens automatically. With the exception of those overrides and the occasional vacation hold I never have to touch the thermostat, it's great.
posted by rabbitrabbit at 11:56 AM on April 25, 2018 [3 favorites]

nthing honeywell. The installation instructions were useless, but 1 call solved the problem.

Unless you are home all the time, you need a programmable so you are not freezing for 2 hours when you get home.

We'd like to be able to do this without having to push unresponsive hard plastic buttons hundreds of times while reading a low resolution LCD screen to navigate through days days of the week and times of day.
You will need to do this initially and maybe in 3 years when the battery dies, but it's not that difficult.
posted by H21 at 12:18 PM on April 25, 2018

Different radiators put out different amounts of heat, so some rooms can be too hot and others can be too cold.

This part of the problem is actually not that hard to solve if the too-hot and too-cold rooms are always the same ones.

If the room radiators are really oldschool and don't have any form of flow rate adjustment (i.e. valves for the heating water or baffles for the room air) then you can just selectively insulate part of the radiators in the too-hot rooms, and set your thermostat to get the temperature right in the too-cold ones. Depending on the design of the radiators, insulating them might be as simple as partial wrapping in a blanket.
posted by flabdablet at 12:37 PM on April 25, 2018

It's also worth considering investing in thermostatic radiator valves for all of your radiators - it'll solve the problems of some rooms being too hot and some too cold, and they're fairly affordable (<£10 each).
posted by A Robot Ninja at 12:57 PM on April 25, 2018 [1 favorite]

If I am understanding correctly, this is a single loop hot water system. The hot water is circulated in a series circuit through all the radiators. There is no way to regulate the flow through individual radiators since the flow is the same through all the radiators.

Insulating individual radiators is a possibility.
posted by H21 at 1:07 PM on April 25, 2018 [1 favorite]

There are valves for hot water radiators that can be set at a desired temperature. The valve throttles the amount of water admitted into the radiator.

Best way to set this up is to have the thermostat in a room that does not have a radiator (hallway) or at least, is centrally located. (Radiators are usually found on exterior walls, since that's how cold from outside makes it inside.)
The thermostat will only call for heat during the times of day that you want it warmer. If there's no call for heat, there's no hot water for the individual valves to admit, so it doesn't matter if they're wide open.

I would be extremely surprised if the system were set up in series (as mentioned by H21). Even the Dead Men of old who designed the systems needed to shut off one room or another, independent of the whole system.

Another thing to note: make sure there is, if not a whole radiator cover, at least a reflective sheet behind each radiator. The difference is amazing.
posted by notsnot at 2:00 PM on April 25, 2018

I use a Nest with all the pseudo-smart stuff turned off. Gives me a nice big readable temperature, turn the knob to change it. Also I can change temperature it from an app on my phone while in bed, or from anywhere.
posted by w0mbat at 4:18 PM on April 25, 2018

I have the same kind of heating system and an older Nest. It's been great and waking up to a warm house is wonderful. It does seem to be able to figure out how early it needs to turn on to make that happen.
posted by sepviva at 5:50 PM on April 25, 2018