How to set up a boiler plant - 2 heat sources under one installation

Hi. I have quite a problem with a boiler room that I need to convert. Hydraulically the matter is simple but the problem arises with the control. I have 2 boilers in there: a starmark eco-pea boiler and a Viessmann 100W gas condenser. I agreed with the investor that he would like the gas boiler to support the system in the event of a fade-out in the solid-fuel boiler. I have 3 pumps in the system and a mixer with an actuator for the radiators. The underfloor is to run all the time even when the set temperature is reached in the house.I came up with this: The TECH ST-408N master controller will control the pumps and actuator as well as the circulation pump and will interact with the room controller. My question is whether it is possible to connect a Viessmann boiler under the st-409n in the need to heat function so that it switches on when it senses a drop in the supply temperature with a solid-fuel boiler Above all, will the Viessman work with the tech company? I also have a tech company boiler controller on my solid fuel boiler and would also connect it to the ST-408N. I have looked in various sources and nothing. And the service doesn't know anything about it. Please help or any simpler solution.

I have a similar situation at my place - a gas boiler and a fireplace with a mantle. When I fire up the fireplace it takes over as the main heat source. The trick is that the boiler I have uses the return water temperature as the control parameter. This means that when the fireplace heats, the cooker "deduces" that it does not need to heat when there is hot water in the return. What is important is that the cooker and fireplace installations meet in a hydraulic coupling, behind which there is an additional pump for the radiator circuit (controlled by the cooker and fireplace - with priority for the fireplace) and the floor installation has a three-way valve behind the coupling and a separate pump controlled only from the gas cooker. The only common point of control is the pump responsible for the radiator circuit - when the fireplace is working, the fireplace controller via a relay forces it to work, if the fireplace is not working it is connected normally to the gas cooker. Generally - it works for me.

I think I will also have to use a relay to switch the floor pump and the rest will be connected to the eco-pea boiler controller. in this system, the pea boiler will control the central heating and DHW pumps and the floor pump from the relay, while the gas boiler will control the floor pump from the relay.

I wouldn't risk controlling the underfloor other than through the gas boiler - if something doesn't play you can overheat the system. The water coupling causes the gas boiler to be cheated because it gets water heated by the fireplace, but the pumps and the floor valve control the floor correctly. And one more thing - I don't heat the DHW cylinder directly from the fireplace, and I don't have a 3-dw valve in the radiator system but take directly from the coupling.

Before the floor pump there will be a mixer limiting the temperature, so the system will not operate at high parameters. As for the HUW, the pump will be controlled from the boiler to the tank. The gas boiler will take care of this on its own.

I can write you a program, I just happen to have a Carel PCO2 controller with display for sale for 300 plus a programmer for 4 hundred. I also have Belimo analogue and three point actuators for sale. Carel is a dedicated HVAC or ELPiast controller

d3cd6fc16 Hello, I have quite a problem with a boiler room which I need to convert. Hydraulically the matter is simple but the problem arises with the control. I have 2 boilers there: a starmark eco-pea boiler and a Viessmann 100W gas condenser. I agreed with the investor that he would like the gas boiler to support the system in the event of a fade-out in the solid-fuel boiler. I have 3 pumps in the system and a mixer with an actuator for the radiators. The underfloor is to run all the time even when the set temperature is reached in the house.I came up with this: The TECH ST-408N master controller will control the pumps and actuator as well as the circulation pump and will interact with the room controller. My question is whether it is possible to connect a Viessmann boiler under the st-409n in the need to heat function so that it switches on when it senses a drop in the supply temperature with a solid-fuel boiler Above all, will the Viessman work with the tech company? I also have a tech company boiler controller on my solid fuel boiler and would also connect it to the ST-408N. I have looked in various sources and nothing. And the service doesn't know anything about it. Please help or some simpler solution.