Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Master Temperature Control of Rooms

LJPurvis
LJPurvis Member Posts: 17
All,

We live in an area where a private Geothermal company provides pressurized hot water to the house. This neighborhood (and the house) has been using this company for over 100 years. We bought the house a couple of years ago and want to do some upgrading.

A couple of things to note:
1. The water comes into the house at 165 deg F.
2. It is an open system. Once we use the water we dump it into a creek behind the house.
3. The setup is unique for the neighborhood as our radiators are not in series. We have a supply line and a return line. Each room has its own supply and return. Most rooms have only one radiator but several of the larger rooms have two radiators. In the rooms with two radiators, those radiators are in series.
4. The whole house is controlled by an old mercury thermostat in the dining room. This thermostat feeds a Honeywell mercury switch relay that opens a valve that is situated at the end of the return line (just before it exits the house and dumps into the creek).
5. We live in the U.S.

The main issue: The dining room dictates when the whole house heating will be turned off. This creates hot spots (primarily upstairs) and cold spots in the house. With the rooms having their own supply and return we would prefer to control each room individually.

I had considered the Honeywell Evohome system. It looks perfect; a master controller using Bluetooth to control each room. However, it appears I would have to use US to UK voltage converters in order to operate the hardware. I don't believe I want to do that.

I cannot find where I can get the same system in the U.S.; a master controller to control each room. The best I can see is using a Nest or Ecobee in each room to control a valve on the return line from each room. However, this requires a thermostat in each room plus wiring to a relay. This is an old house with lathe and plaster and I prefer to not run any wires.

I have also found Bluetooth TRVs that I could place in each room and control via my phone. But I don't want to control it via my phone; I would prefer a master house controller.

Thoughts?

Comments

  • hot_rod
    hot_rod Member Posts: 21,975
    this company has some nice wireless controls. I find see a wireless TRV they offer just last week, very quiet. Prices seem reasonable.

    I saw the entire platform at a wholesalers.


    https://www.salusinc.com/products/#hydronics
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • hot_rod
    hot_rod Member Posts: 21,975
    radiator valve
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • LJPurvis
    LJPurvis Member Posts: 17
    That is awesome. Thank you. The only difference (and not really too terrible) is the Evohome handles all rooms from a single controller while these use one controller/room. However, the good thing about this system is it uses the thermostat to measure the temperature of the room and NOT the TRV (which I think is better).
  • hot_rod
    hot_rod Member Posts: 21,975
    And the smart plugs to start the Keurig and waffle iron :)
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    LJPurvis
  • Paul48
    Paul48 Member Posts: 4,469
    Constant circulation and a Taco "I" series valve?
    Rich_49SuperJSuperTech
  • LJPurvis
    LJPurvis Member Posts: 17
    Paul, I do not want to do constant circulation as it is an open system. All water is dumped into a creek behind the house after it runs through the system. We are actually trying to reduce the amount of "dump" we perform.
  • ratio
    ratio Member Posts: 3,614
    Maybe something like this would work for you? No power required, does not sense at the head, individual control, mounts on a TRV body. I'm pretty sure they are 100% cutoff, at least I know they will hold back 2# steam.
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Why not just regular zone valves for each room wired directly to the thermostat? They supply constant pressure correct?

    Best comfort is a outdoor reset mixing valve and your own secondary circulation loop. Then zone valves and stat for each room. Use a regular zone controller for master circulator control. Could use constant pressure or delta t.
  • Paul48
    Paul48 Member Posts: 4,469
    edited January 2018
    With an "I" series valve, you would use much less hot water. Only what is needed to heat the house. What would normally be going back to the boiler, in a normal application, would be going to the creek. You'd have to use a stainless or brass circ, but I don't see how it would not work. Maybe I'm missing something.
    SuperTech
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    I’m surprised the environmental folks allow 140f water to go back to a creek... unless this water normally goes there.

    If you are billed by water use you want to reduce flow and increase delta T somehow. But it might just be a flat monthly fee.
  • ChasMan
    ChasMan Member Posts: 462
    I like the part where he said. We live in U.S. No doubt. I can't imagine this being anywhere else. My office building has 10.4 kw electric heaters every other floor in the stairwells. They run constantly yet we have to sign for a box of pens. If you are paying by the gallon or whatever, I wouldn't let that water out of my house until it was room temp.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    OP said it's an "open" system, with radiators. If you are using cast iron radiators, and this is the case, you have a WHOLE lot more problems coming at you than just being able to individually control the flow to the radiators. Flow control does no good when you can't get any flow through the radiator. For me and my money, I'd just go with conventional TRV's and let it ride.

    If in fact it IS cast iron radiators, you could set a heat exchanger to extract the heat from the geothermal system, and set up your own controllable closed loop system, but if its been running for 100 years, the corrosion damage to the radiators has already been done.

    I worked on a similar system near Detroit Lakes in Oregon that served 150 out buildings. Very interesting project, until I blew up their well... When I asked fro a pump to flush the heat exchanger, they brought me a fire truck...

    What part of the US are you in?


    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    Rich_49Zman
  • LJPurvis
    LJPurvis Member Posts: 17
    Mark,

    I am in Idaho. You are correct; they are cast iron radiators. The house stays very warm we just would prefer to control via each room vs a single control point.

    We do pay a flat annual fee so there is neither extra cost nor savings by adjusting the way it was done before we purchased the home.

    The home was built in 1907. We are the second family to own it since it was built. There is nothing wrong with the current system or radiators. The heating runs in the winter. We turn it off and drain it in the summer.

    As for the question by one person about dumping it into the creek...although it "looks" like a creek, it is actually an irrigation creek that was built for this neighborhood to dump the hot water. The geothermal water comes bubbling out of the ground and runs into the local creeks, irrigation canals, etc. It is a fairly unique situation. Over a hundred years ago the neighborhood started the Warm Springs Geothermal Company. They capped off one of the geothermal springs and fed it to the houses on Warm Springs Avenue. It has been that way since around 1900. Our house is actually the last house on the line.

    Since it is geothermal we do need to be careful about the materials we use. Copper and brass are eaten alive by the sulfur in the water. We use PEX. Before that, all piping in the house (and there is still quite a bit of it) is black iron (steel). I use stainless steel for most of my new valving.

    Anyway, it is not a current "problem". It is just something we want to enhance. We can control each room by adjusting the manual valves. But the thermostat in the dining room ultimately controls when the water will be supplied (by shutting of the return valve). I just want to get rid of that master return valve and replace it with room controls.

    I am currently looking at SALUS. However, as I start to implement it I may have to install a new discharge line so that all updated rooms feed to that line instead of the current line which would allow the dining room to negate any updates.
    Mark Eatherton
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    This one?

    http://bwswd.com

    Cool system. Seeings as how its been around for over 100 years, I guess they know component selection better than anyone, but I would be leery of using cast iron on an open system...

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    SuperTech
  • LJPurvis
    LJPurvis Member Posts: 17
    Mark,

    Yep, that's us. I am replacing all piping with PEX as I work/upgrade different areas (along with upgrading old knob-and-tube wiring!).

    I replaced the discharge from inside the house to the creek with PEX. The first old iron pipe is about 50' away from the end of the discharge. Also, the end of the discharge is always underwater.

    I'm having a lot of fun and really enjoy doing the work myself.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    edited January 2018
    Your final discharge water could be used (with a flat plat heat exchanger) to melt snow...

    I'm using solar panels to melt mine.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Gordy
    Gordy Member Posts: 9,546
    edited January 2018
    Interesting setup along with the ci rads eating sulfur enriched water for over 100 years. Are you sure radiators in cooler rooms are getting full output? Not partially plugged.

    Why not move thermostat to coolest room, and try to balance by decreasing output to the warmer rooms?
  • JUGHNE
    JUGHNE Member Posts: 11,038
    So is this "free" heat energy free, probably not. How do they meter it per customer? Is the "dump water" metered?
  • LJPurvis
    LJPurvis Member Posts: 17
    @Mark Eatherton - We plan on using the discharge to melt snow. We are putting in a new driveway this spring and will be implementing a system to pipe mixed water through PEX embedded in the concrete. We have to mix it as it would be too hot if we did not. Our discharge runs about 140-150 deg F. We want to pump 130-ish under the concrete. I learned 140+ temperatures will cause the concrete to crack.

    @Gordy - I am not sure the radiators in any room are getting full output. The concern isn't "really" the cool spots. It's the upstairs. If the dining room is set to 70 deg F, by the time it turns off the return it is more like 75+ deg F upstairs. This is with several of the upstairs radiators turned completely off. The hot air rising thing going on there.

    @JUGHNE - "Free"? No. We pay a flat annual rate for the geothermal. It is not metered per customer. It is metered at the pump station so they know how much water is used annually. We are not allowed, by the city, to discharge into the waste water. Understand, if this source had not been capped off over a hundred years ago, the well would just continually pump 175 deg F water into the environment. Idaho has an abundance of geothermal water coming out of the ground. http://www.idahohotsprings.com/hot_springs/idaho_hot_springs.htm
    Many utility companies take advantage of this resource to generate electricity. Our neighborhood uses it to heat houses. Some (like us) use a heat exchanger to heat the hot water. Others actually use the geothermal as their hot water. It comes out of their faucets between 160 - 170 deg F! And a very few (we will soon be joining this crowd) use it to keep their driveways free of snow and ice. I want to find additional uses as I feel it is a waste to dump hot water before extracting as much energy out of it as possible. We only dump, however, when the system (i.e. dining room) is calling for heat or when the heat exchanger is heating the water.
    Mark Eatherton
  • hot_rod
    hot_rod Member Posts: 21,975
    I've read there are some systems generating electricity via steam with 165F temperatures with some of the new refrigerants. I think the Chena Hot Spings near Fairbanks does. A few small projects around Reno also.

    It would be fun to get all your energy from that hot water flow, heat, cool, DHW and electricity.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • LJPurvis
    LJPurvis Member Posts: 17
    Yeah. US Geothermal has plants operating in Raft River Idaho and Neal Springs Oregon (right on the border of Oregon and Idaho).
  • JUGHNE
    JUGHNE Member Posts: 11,038
    So for snow melt I suppose you would use a heat exchanger and run a glycol mix thru the tubing?
    Mark Eatherton
  • ratio
    ratio Member Posts: 3,614
    I think I'd just let it run after the temperature drops to say 35°. Remember, this is a natural phenomenon, we shouldn't interrupt it.
  • LJPurvis
    LJPurvis Member Posts: 17
    @JUGHNE - Well, I wasn't going to do that. I was going to use a mixing valve to cool the water off to 130 and just run it through and dump it. But, I like your idea!
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    LJPurvis said:

    @JUGHNE - Well, I wasn't going to do that. I was going to use a mixing valve to cool the water off to 130 and just run it through and dump it. But, I like your idea!

    You're going to have to use a HXer and antifreeze, otherwise you take a chance on freezing and breaking tubing. 5/8" tubing at 9" O.C., 400 foot max length. When you're ready, come back and we'll talk you through it.

    ME

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    LJPurvis
  • LLazo
    LLazo Member Posts: 1
    I just pulled the trigger on the European Evohome system. I have a 3 story, 1904 house in Denver that is piped for two zones, main floor is one zone, second and third floors are another. 14 radiators. My plan is to control all radiators independently. I bought a the main controller (ATC928) and relay (BDR91) and 4 radiator controllers (HR92).

    Here's what I've learned so far.
    1. The controller uses 5v dc, so any usb cable with a 5.5mm barrel end will power it. It needs at least 1 amp.
    2. The relay will accept 120v, no problem controlling my Honeywell zone valves.
    3. The system discovered and joined my wifi with no issues
    3. The radiator controllers are very responsive. Danfoos TRV.
    4. Initial set up was a little tedious but once you get the hang of it it goes pretty smoothly.
    5. I have not found a way to connect to the system with computer or phone. The phone app is not available in the US and you have to have a European address to set up the Total Comfort system on the computer. I faked an address and it immediately changed the time on my main controller.

    I'll post more as I learn.
  • SuperJ
    SuperJ Member Posts: 609
    Paul48 said:

    With an "I" series valve, you would use much less hot water. Only what is needed to heat the house. What would normally be going back to the boiler, in a normal application, would be going to the creek. You'd have to use a stainless or brass circ, but I don't see how it would not work. Maybe I'm missing something.

    This is a decent idea, constant circ doesn't mean constant dump, it means you recirc the water in the house and just add enough new water (and dump the same amount) to keep the house warm. The valve mentioned has the capability of running off outdoor temperature to vary the water temp or modulating to maintain an indoor temperature (depending on which one you get). Your house would be more comfortable and you would likely dump substantially less water.

    Lots of zoning options too, like the TRVs hot rod mentioned.
    SuperTech
  • SuperTech
    SuperTech Member Posts: 2,134
    Did you consider any of the products that Tekmar offers? I remember seeing some home automation systems from them, not sure if it could be used on your application or not.