Results 1 to 8 of 8

Thread: Understanding the way the HM80 works with Evohome

  1. #1
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default Understanding the way the HM80 works with Evohome

    Having just managed to get my hands on an HM80, I was keen to find out how it worked with Evohome. I am also trying to see what the radio comms between the Evohome controller and the HM80 are but for the life of me I cannot see that on my HGI80. But that is a different issue.

    I first had great difficulty binding the HM80 to the controller. I basically couldn't put the HM80 into pairing mode. The instructions say to hold the two buttons down for 4 secs, but no matter what I did I couldn't get it to start the pairing process. Now I think I have figured the trick to do that.

    You have to basically press 1 button make sure the corresponding LED lights up, then press the second button. You will know that you have started the binding 4 sec timer, when NONE of the LEDs are lit while you are pressing both buttons. If even one of them is lit or comes on, then you have not pressed the buttons correctly or you have released them too soon. You then need to start again.

    The same trick is to be used to clear all previous binding and reset the HM80 to factory defaults. You start off as though you are putting the HM80 into pairing mode, after 4 seconds the LED 4 starts to blink evenly on/off, keep the two buttons pressed for more than 10 seconds and then LED 4 will blink differently. When it's off longer than it's on, it has been reset. Again, NO other LED should be lit when you are doing either the binding or the resetting.

    It took me so long to figure those two bits out. Hopefully this helps others.

    Now to the bits that I don't understand.

    In Evohome, there are 5 zone types that an actuator can be paired as. The manual tells you to use the "Mixing Valve" zone type for the HM80. The HM80 will not pair if the zone type is set to Zone Valve. But strangely it does pair with the Evohome if I set the zone type to "Underfloor Heating". However with Underfloor Heating, none of the Parameters for the HM80 can be set. But these parameters can be set when the zone type is correctly set to "Mixing Valve".

    The Evohome instructions say
    "The Mixing Valve Controller will not provide a heat demand to the boiler. If you want this zone to provide a heat demand change the Heating Type from 'MIXING VALVE' to 'ZONE VALVES' once the Mixing Valve controller is bound. There's no need to re-bind any device Ė The Mixing Valve Controller will still operate as intended and the evohome Controller will send the heat demand to the boiler."

    I cannot get to work on my Evohome Wifi with the latest firmware. I have two issues with this instruction.
    1. Keeping the zone as "Mixing Valve" I can see a Heat Demand in the System Summary, even though the instructions say it won't provide a heat demand.
    2. If I change the zone type to "Zone Valve", the controller forces me to rebind the device but because the HM80 won't bind when the zone type is set to "Zone Valve", I land up with the zone that has the RF binding set to Not bound.

    So has the manual not kept up with the firmware changes or am I doing something wrong?

    I have also noticed that the HM80 takes several minutes to respond to any instruction from the controller. The BDR91s on the other hand seem to respond almost instantly. The consequence of this is that the Boiler is fired up via the OT Bridge, but the water is just circulating around the auto bypass until the HM80 finally opens.

    Can anyone who has experience with the HM80 help explain what I am seeing or doing wrong.

  2. #2
    Automated Home Guru
    Join Date
    Sep 2018
    Location
    Scotland
    Posts
    176

    Default

    Quote Originally Posted by bruce_miranda View Post
    Having just managed to get my hands on an HM80, I was keen to find out how it worked with Evohome. I am also trying to see what the radio comms between the Evohome controller and the HM80 are but for the life of me I cannot see that on my HGI80. But that is a different issue.

    I first had great difficulty binding the HM80 to the controller. I basically couldn't put the HM80 into pairing mode. The instructions say to hold the two buttons down for 4 secs, but no matter what I did I couldn't get it to start the pairing process. Now I think I have figured the trick to do that.

    You have to basically press 1 button make sure the corresponding LED lights up, then press the second button. You will know that you have started the binding 4 sec timer, when NONE of the LEDs are lit while you are pressing both buttons. If even one of them is lit or comes on, then you have not pressed the buttons correctly or you have released them too soon. You then need to start again.

    The same trick is to be used to clear all previous binding and reset the HM80 to factory defaults. You start off as though you are putting the HM80 into pairing mode, after 4 seconds the LED 4 starts to blink evenly on/off, keep the two buttons pressed for more than 10 seconds and then LED 4 will blink differently. When it's off longer than it's on, it has been reset. Again, NO other LED should be lit when you are doing either the binding or the resetting.

    It took me so long to figure those two bits out. Hopefully this helps others.

    Now to the bits that I don't understand.

    In Evohome, there are 5 zone types that an actuator can be paired as. The manual tells you to use the "Mixing Valve" zone type for the HM80. The HM80 will not pair if the zone type is set to Zone Valve. But strangely it does pair with the Evohome if I set the zone type to "Underfloor Heating". However with Underfloor Heating, none of the Parameters for the HM80 can be set. But these parameters can be set when the zone type is correctly set to "Mixing Valve".

    The Evohome instructions say
    "The Mixing Valve Controller will not provide a heat demand to the boiler. If you want this zone to provide a heat demand change the Heating Type from 'MIXING VALVE' to 'ZONE VALVES' once the Mixing Valve controller is bound. There's no need to re-bind any device Ė The Mixing Valve Controller will still operate as intended and the evohome Controller will send the heat demand to the boiler."

    I cannot get to work on my Evohome Wifi with the latest firmware. I have two issues with this instruction.
    1. Keeping the zone as "Mixing Valve" I can see a Heat Demand in the System Summary, even though the instructions say it won't provide a heat demand.
    2. If I change the zone type to "Zone Valve", the controller forces me to rebind the device but because the HM80 won't bind when the zone type is set to "Zone Valve", I land up with the zone that has the RF binding set to Not bound.

    So has the manual not kept up with the firmware changes or am I doing something wrong?

    I have also noticed that the HM80 takes several minutes to respond to any instruction from the controller. The BDR91s on the other hand seem to respond almost instantly. The consequence of this is that the Boiler is fired up via the OT Bridge, but the water is just circulating around the auto bypass until the HM80 finally opens.

    Can anyone who has experience with the HM80 help explain what I am seeing or doing wrong.
    I had no issues with the HM80 and latest firmware but didnít try to rebind it.

    I think I see what you mean, with the latest firmware if you try to change the zone type the controller will remove any bound devices.

    I have a paper copy of the latest evohome installation guide, which includes the BDR91T heat pump details. Interestingly the HM80 instructions no longer indicate that the zone type should be changed.

    Perhaps that workaround is no longer needed. Do you see the boiler fire when the only demand is from the mixing valve zone?

  3. #3
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default

    So I wasn't going mad.
    Yes the boiler does seem to fire up just with the zone type kept at Mixing Valve. And like I said the Heat Demand shows up in the System Summary too for that zone, even when it is kept as Mixing Valve.
    I wonder if the electronic copy of the Evohome has been updated too. I'll try and check.

    p.s. Found it : https://getconnected.honeywellhome.c...guide%20EN.pdf
    Last edited by bruce_miranda; 21st January 2021 at 11:17 PM.

  4. #4
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default

    Does the controller register a fault in the log if it cannot communicate with the HM80 after a while?
    Also the new manuals say that HM80 is now an obsolete product. What has it been replaced with to control Mixer Valves?

  5. #5
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default

    Over 24hours of the HM80 unplugged and the Evohome controller hasn't realised that yet!! No errors in the fault log, nothing.
    Also how can you have multiple HM80 in your system, if the controller is just sending out new parameters as a information broadcast message, rather than from the controller to the HM80. If there are multiple HM80s in a system, won't they all just update themselves when the controller sends out new parameters.
    I am still no closer to finding out why the HGI80 isn't catching any comms from the HM80.

  6. #6
    Automated Home Guru
    Join Date
    Sep 2018
    Location
    Scotland
    Posts
    176

    Default

    Iíve noticed similar behaviour with a BDR91 and the latest firmware. I prebound my system prior to installation. The BDR91 controlling my towel radiator circuit was last to be installed. I saw no errors.

    Does your HM80 test zone still have setpoint changes?

  7. #7
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default

    Yes that zone has the maximum 6 set point changes, and with each change the Heat Demand in that zone changes. But the controller has no clue that the HM80 has been completely powered off.

  8. #8
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,567

    Default

    I have come to the conclusion that the HM80 doesn't say a word over the radio. It only listens to instructions and acts on them. The Controller just simply expects the HM80 to obey and never requests any information back from the HM80.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •