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Kirjoittaja Aihe: Optimal Delta T secondary, R410A, Vitocal 300G?  (Luettu 317 kertaa)

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Greetings from Sweden and congratulation on your independence day!

My rigg:

Vitocal 300G 10,3 kW, 400 liter buffer cylinder, 390 liter stand alone Warm water tank for household water.
240 m2 house
110 meter well
330 meter soil
Underfloor heating and over dimensioned radiators. The same load temperatures on underfloor as radiators.

Have any of you Vitocal owners made any measurements on witch delta on the secondary is the most optimal for det COP?
When stating COP in the heat pump manuals they have a DeltaT 5° B0 W35 COP 5,01 on my Vitocal 300G 10,3kW. Can we assume then that a DeltaT of 5° is the optimal?
I have run my rigg with a delta of 5° between heat pump and buffer. And now i have been running with a delta of 6° between heat pump and buffer for a while.
My imagination thinks that it runs much smoother with a delta of 6°.
It runs very tight against wanted load temperature (curve/buffer). And very balanced flows to and from buffer cylinder.
The most time of the runs it runs with the cold return temperature from underfloor/radiators, so with the lift on the heat pump it stays almost spot on the wanted buffer temp. Just the last maybe 15 min it goes a couple of degrees over the wanted temp when the return from heating circut gets warmer. It usually stop +2° when the buffer has reach its temp acc to curve.
But i have no ide if the COP is better or worse with delta 6 than 5. Do you have any ideas?



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Vs: Optimal Delta T secondary, R410A, Vitocal 300G?
« Vastaus #1 : 08.12.17 - klo:08:49 »
I called a technician on Viessmann. He claimed 7° delta is the most efficient differential.

Any comments on that?