Rads upstairs getting hot when hot water is on - gravity fed

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • ksharma5
    Automated Home Lurker
    • Aug 2006
    • 7

    Rads upstairs getting hot when hot water is on - gravity fed

    Hi - am new to this forum so please bear with me

    I wonder if any of you can help - I have a gravity fed system (Sime Superior 80 boiler) and when I switch the hot water only on, the rads (upstairs mainly) get warm/hot. I have checked the three port valve and it is changing to the correct positions when the hot water and heating is on. Can someone point me in the right direction please ?

    Thanks very much

    Chris
  • ksharma5
    Automated Home Lurker
    • Aug 2006
    • 7

    #2
    Re: Rads upstairs getting hot when hot water is on - gravity

    Forgot to say that some of the rads are getting air in the system so am having to constantly bleed the air out of the rads.

    Thanks

    Comment

    • sunbeam
      Moderator
      • Feb 2006
      • 261

      #3
      how long has it done this,
      between the pump and the diverter valve there might be a by-pass with a gate valve on it ,is it open,if so close it.

      Comment

      • ksharma5
        Automated Home Lurker
        • Aug 2006
        • 7

        #4
        Re: Rads upstairs getting hot when hot water is on - gravity

        Hi - thanks for your response.

        It has done this for quite a while. I cannot see a diverter valve between the pump and the diverter valve, however, there is a pipe going upstairs from the oiler (I think its the flow pipe) which has some kind of valve on it - how can I tell if its open ?

        Comment

        • sunbeam
          Moderator
          • Feb 2006
          • 261

          #5
          Re: Rads upstairs getting hot when hot water is on - gravity

          are we sure its air in the rads,the next time you have to bleed them have a lighter ready and try and light the air if it lights it's not air,your system needs some inhibitor in it.
          if that then solves the problem with the air,then i would say the 3 port valve is passing.

          if it turns out that the air will not light then it is air,getting into the system some how,

          how hot are the rads and hot water,if there overly hot then the boiler stat may have gone,

          if not then i'm thinking the hot water return could be blocked,

          does the hot water from the diverter to the cylinder go into what is called a "hot rod" that is. the two pipes go into the top of the tank, or do they go into the side.

          hope this makes sense

          Comment

          • ksharma5
            Automated Home Lurker
            • Aug 2006
            • 7

            #6
            Re: Rads upstairs getting hot when hot water is on - gravity

            Hi - having attempted to light the air - it did infact light - quite a long flame too! So I will put some inhibitor in ASAP!

            Regarding the second point, the pipe going into the top of the diverter valve is coming out from the side of the cylinder. The pipe going into the middle of the valve is coming out from the loft and the one coming out the bottom of the valve is going straight down. Not sure if this makes sense ?

            Thanks once again!

            Comment

            • sunbeam
              Moderator
              • Feb 2006
              • 261

              #7
              Re: Rads upstairs getting hot when hot water is on - gravity

              yes makes sense.

              i would suggest now that the diverter is passing to central heating slightly when on hot water only,

              do you know what make it is?

              are there any gate valves to isolate the diverter?if so you might be just as well turning the one off that is on the central heating side, in summer.

              Comment

              • ksharma5
                Automated Home Lurker
                • Aug 2006
                • 7

                #8
                Re: Rads upstairs getting hot when hot water is on - gravity

                It is a Honeywell Sundail Y plan 3 port valve. I dont think there are any gate valves to isolate the diverter. Is there a way of checking if the 3 port valve is slightly on central heating whilst on hot water only ?

                Comment

                • sunbeam
                  Moderator
                  • Feb 2006
                  • 261

                  #9
                  you could put the clock on water only and feel at pipe coming out of the 3 port going to the heating,

                  or put the clock on water and heating , turn the room stat down and feel the pipe

                  it will get warm for a couple of foot after the valve but this is normal,

                  Comment

                  • ksharma5
                    Automated Home Lurker
                    • Aug 2006
                    • 7

                    #10
                    Re: Rads upstairs getting hot when hot water is on - gravity

                    Hello,

                    Apologies for the long delay in responding...I have checked the three port valve (it is a honeywell V4073A1039) and when I switch the mains off, the lever moves with resistance (e.g. I can hear the motor winding), however, when I switch the mains back on the lever is completely loose - and moves freely. Does this indicate that the valve or actuator is faulty ? It only moves automatically when H/W comes on but not for Central Heating.

                    Thanks

                    Comment

                    • ksharma5
                      Automated Home Lurker
                      • Aug 2006
                      • 7

                      #11
                      Re: Rads upstairs getting hot when hot water is on - gravity

                      Sorry, I amend that. There is resistance in the lever when the mains is on but only when the Hot Water is on. When the Hot water is off and the Central Heating is on then the lever moves freely.

                      Thanks for your help in advance.

                      Comment

                      Working...
                      X