Recent content by Johntheo5

  1. J

    Worcester Greenstar CDi Compact - Return Temp (i14) much higher than pipe surface & rads

    The radiator surface should read like my own below, very close to the boiler flow temperature where shown, along the TOP, my boiler and rad flow/return temperatures were 65C/58C, I don't have a condensing boiler so not too worried about the return temperature as + or - 10C (return) is only about...
  2. J

    Worcester Greenstar CDi Compact - Return Temp (i14) much higher than pipe surface & rads

    Are you talking about the rad return when you say it managed to get up to 42C. If you cant get any more flow through the rads which apparently you can't with the pump running at that high speed then the only other way is to raise the boiler flowtemp, from the present 63.5C to say 70C which will...
  3. J

    A spokesperson said: "Turning the thermostat up higher does not make your home warm up any quicker." Really?

    Can't really comment on the "smart" type but it certainly makes a difference on the simple TRV because even with a cold room the valve opening is less at 20C than at 22C, despite EPH, below, stating otherwise. I presume the Energenie or likewise, being smart, start thottling down the flowrate...
  4. J

    Worcester Greenstar CDi Compact - Return Temp (i14) much higher than pipe surface & rads

    Your boiler max output to CH (rads) is 24kW under your operating conditions, the output at 32% burner modulation is 7.68kW. The circulation flow through the rads at 66C flowtemp and using your measured return temp of 48C is 6.11LPM, the circulation flow through the boiler at 66C+ 58C return, is...
  5. J

    Worcester Greenstar CDi Compact - Return Temp (i14) much higher than pipe surface & rads

    Possibly because the internal bypass is opening which it may do if the pump speed is very high and a possible restriction in the main heat exchanger, have a look at i16 which will give the pump speed (modulation) in %., with boiler running. Is this the pump setting you are using? Edit. Also...
  6. J

    Oil boiler on an ASHP designed system

    The above concern is a oil fired boiler, kerosene contains a very small % of sulphur I think, and acid dewpoint is well over 100C, so maybe this is why a minimum 40C return temperature is required. I spent over 30 years running 50mW boilers on a mixture of nat gas with up to 15% bio gas from a...
  7. J

    Oil boiler on an ASHP designed system

    Grant and I think Firebird specify a minimum return temperature of 40C to prevent corrosion of the primary HEX, the secondary HEX is stainless, a bit surprising as one would think that the gases leaving the primary would be well avove the due point and at ~ 150/200C with a flue gas exit temp of...
  8. J

    Help Required ... 3 Way Valve not always switching to Hot Water

    I'm no Michael Angelo, nor a electrician and my elec friend who modified his valve has passed on but his MPV lives on but I think this is where it should be installed, see the "relay" above the cylinder stat. The relay coil is energised from the roomstat calling, white wire, the contacts make &...
  9. J

    Help Required ... 3 Way Valve not always switching to Hot Water

    Install Relay as shown below, "SPST Mains Relay"
  10. J

    Help Required ... 3 Way Valve not always switching to Hot Water

    You mean install a relay like in post #37?, you dont require anything remotely as powerful as a 30A, the actuator motor runs at around 10 watts max so something like a 2 to 3A, say 5A if easier to source.
  11. J

    Help Required ... 3 Way Valve not always switching to Hot Water

    Are you talking about the switch on your programmer getting very hot or the 3 way valve actuator getting quite hot?, A SPST is basically a on/off switch., its a single point, single throw, one way switch, or something like that.
  12. J

    Blocked heat exchange plate

    It might be worth getting the mains water and the scale analysed/tested since this is the common denominator, even though the primary side was not being topped up and you were getting the same problem, the system was probably refilled from the mains. If not done so, Install a combined mag &...
  13. J

    Blocked heat exchange plate

    You say the rads are getting bunged up which means the primary water side, you mention the exchanger plate, do you mean the main boiler heat exchanger or is it a combi boiler which will have a PHEX (Plate heat exchanger).? If it is a combi then the DHW side of the PHEX should/might show signs...
  14. J

    Vaillant eco tec 615 is it big enough

    Your boiler is actually oversized so at a 5.4kW heat loss but if your 14 rads+system contin say 90L of water then it will take ~ 20/30 minutes for them to reach say 65C from a cold 15C on a morning start up which is normal enough IMO.
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