Connection of heat pump with PV system

[Priyanka]

We have "Vitocaldens 222-F HAWB-AC 222.A29" heat pump system.

In our pursuit to activate "Operating State 3 (use of surplus PV energy)" of the smart grid for this heat pump, we aim to establish a connection between the PV system and the heat pump via relay switching contact.  We did come across a mention of achieving a similar outcome through an energy meter. Consequently, I have a few questions:

1. Is it possible to establish the required contact via relay, and if so, could you kindly guide me to the relevant information on this option?
2. If the only available option is through an energy meter, could you clarify whether it must be a Viessmann energy meter or if compatibility exists with other energy meters in the market?
3. Additionally, is it feasible to obtain information about the heat pump's activities, (e.g. Own energy consumption is active), directly from our gateway?

[Flo_Schneider]

Hello Vyavahare_Priyanka,

the SmartGrid function can be executed directly on the heat pump control via contacts 216.1 (B) or 216.4 (A). This is controlled via a separate contactor, which establishes a potential-free contact between X3.1 and 216.1 (B) or 216.4 (A).

Note:
- If Smart Grid is connected to the two digital inputs on the basic circuit board ("Enable Smart Grid 7E80" on "4"), the external connection for the heating/cooling circuits must not be switched on ("Remote control 2003" on "2"). Otherwise Smart Grid is not active.
- The electric supply company block is included in the Smart Grid range of functions. Therefore, in this case, the electric supply company block signal must not be connected to connections X3.6 and X3.7.

The functions that can be executed via these are as follows:

■ No contact closed: Heat pump is in normal operation

■ Contact (A) closed: electric supply company block
- Compressor OFF
- Heating water instantaneous water heater can be switched on ("Output for heating water instantaneous water heater with electric supply company block 790A").

Contact (B) closed: Operation of the heat pump with adjusted temperature setpoints for various functions. The changes are set with the following parameters:
- DHW heating: "Smart Grid setpoint increase for DHW heating 7E91"
- Buffer tank heating: "Smart Grid setpoint increase for heating water buffer tank 7E92"

- Room heating: "Smart Grid setpoint increase for room temperature heating 7E93"
- Room cooling: "Smart Grid setpoint reduction for room temperature cooling 7E95"

- The compressor only switches on when required. The valid switch-on conditions for the respective function must be fulfilled. A time phase must be active in the time program for the respective function.
- The adjusted temperature setpoints have no effect on the auxiliary heaters. The additional heaters are switched off at the limits that apply without Smart Grid.

■ Contact (A) and (B) closed: The system components are heated to the set max. temperatures or cooled to the minimum temperatures. The compressor switches on
on immediately, even if no time phase is active in the time program.
Max. Temperatures for various functions:
- DHW heating: "Max. DHW temperature 6006"
- Buffer tank heating: "Max. buffer tank temperature 7204"
- Room heating: "Max. flow temperature heating circuit 200E"
- Room cooling: "Min. flow temperature cooling 7103"

- The heating water instantaneous water heater may be switched on to reach the max. temperatures. The max. level can be set ("Smart Grid release electric heating 7E82").

- The max. temperature setpoints have no influence on the other auxiliary heaters, e.g. external heat generators. The auxiliary heaters are switched off at the limits that apply without the Smart Grid.
- The system components are heated or cooled one after the other according to the defined priorities, e.g. domestic hot water heating before room heating.
- The "Switch-off limit heat pump bivalent operation 7B0F" is shifted to -30 °C so that the heat pump remains in operation even at low outside temperatures.

For the PV function of the system, a 3-phase Modbus energy meter is required, which can be obtained from us. However, the meter can only be used if no battery storage is included in the system. Data for the PV energy meter can be read out via the Vitogate.

Best regards
Flo
 

[Priyanka]

To clarify, the way to utilize excess PV energy for the operation of the heat pump is specifically through a 3-phase Modbus energy meter, rather than setting up a relay contact.

[Flo_Schneider]

No, you can of course also use the Smart Grid contact I described.

Best regards
Flo

[Priyanka]

To utilize self-generated electricity, it is necessary to connect floating contact 2 (216.4) to the X3.1 terminal. Simultaneously, temperature adjustments can be made within the "Photovoltaic" settings available in the control panel. Kindly confirm whether my understanding is accurate. Additionally, could you explain the role of the 3-phase energy meter in this process?

[Flo_Schneider]

Smart Grid and the PV function are two completely different things.

For Smart Grid, use the explanation I gave in my first post. The 3-phase Modbus energy meter is required for the PV function. However, this can only be used if the PV system does not have battery storage.

Best regards 
Flo

[Priyanka]

Thank you for the clarification. I have one more question. Can we connect to the heat pump via our gateway through the Modbus? And what are the specifications of the Modbus? Also, could you please explain the highlighted point in the picture in the context of "utilization of power generated on site."

[Flo_Schneider]

The highlighted point only indicates that both can be used in parallel and that the higher setpoint value counts. A Vitogate 300 can be used to access this.

Best regards
Flo

[HdB_ST_57a]

Hallo Herr Schneider,

I have a VITOCALL 200S system  and a Fronius GEN 24 Inverter.

And I have this small connection schema from Fronius :

Can you advise which connectors represent the "K4" and "K3" boxes (circled on the picture below) on the Viessmann connection board ?

Perhaps the : 216.1 (B) or 216.4 (A) ?

And if so does this mean , I only have to connection a small wire between the relaix and and the Viessmann board ? Like in the attached schema ?

[Flo_Schneider]

Hello HdB_ST_57a,

yes, you could use it to perform Smart Grid function 3 by closing contacts 216.1 and X3.1.

Best regards
Flo

[HdB_ST_57a]

Hello Herr Schneider,

Meanwhile i have set-up the Smart grid connection and it is also active (see my screenshot) .

But the heatpump does NOT get triggered to start heating the higher temp in the WarmWater Storage.

I have done the 10 K increase in the Smart Grid menu.

Is there more I need to do ?

[Flo_Schneider]

Take pictures of each side of the system overview when you think the heat pump should be heating. You can get there by holding down the ‘?’ button for approx. 4 seconds.

Best regards
Flo