ᐅ Existing property, looking for a new heating concept

Created on: 20 Jun 2016 08:53
N
nelly190
Hello everyone,
my name is Kevin. A few days ago, I purchased an existing property. Now some renovations are planned.

Current condition:
- Oil heating system from 2004 for heating and domestic hot water
- Hot water storage tank estimated at 220 liters (58 gallons) next to the boiler

House details:
- Built in 1957
- Living area 147 square meters (1580 square feet)
Planned occupancy: up to 4 people

Planned renovations:
- Bathrooms to be refurbished with underfloor heating on the ground floor (5 square meters / 54 square feet) and upper floor (10 square meters / 108 square feet)
- Pellet stove in the living room, which will likely heat the living room and adjacent dining area (approx. 55 square meters / 592 square feet)
- Possible solar thermal system on the south-facing roof

Now to my main questions:
1. I assume I will need two different supply temperatures, right?
2. Is it feasible to use the solar thermal system to provide hot water and underfloor heating, possibly with government subsidies (e.g., BAFA funding), and to have the oil boiler as a backup heat source?
L
Legurit
20 Jun 2016 22:08
How are we supposed to know? What is your actual heating load in the end – can this even be covered by underfloor heating? A pellet stove without a water jacket that presumably heats something is nonsense... if the house is properly insulated, it will get too warm and you would have to open the windows wide... that’s not a viable concept. If the insulation is poor, you will have to get up at night; otherwise, the house will start to mold because it cools down too much.

By the way, you can also run underfloor heating very well with an oil boiler... Heat pumps always work (though they don’t always make sense).
N
nelly190
20 Jun 2016 22:12
The fireplace is only used for supplementary heating in the living room and dining room. Radiators are also installed, of course. How can I determine the heating load that is ultimately estimated?
L
Legurit
20 Jun 2016 22:25
Calculate... Heat loss through the individual building components to the environment.
In the case of your bathroom, you can then determine whether and with what supply temperature you could achieve your desired indoor temperature in the depths of winter using underfloor heating.
Often, it simply makes sense to continue using written-off equipment at first—especially when you are still getting to know the house.
N
nelly190
3 Jul 2016 00:27
So, I have scheduled an appointment with an energy consultant for the week after next. I will see what comes of it.
L
Legurit
3 Jul 2016 00:31
Detached or attached somewhere? I’m sometimes a bit skeptical ;-) What I mean is, always try to understand the motivation of the other person.
N
nelly190
3 Jul 2016 19:11
Our municipality is currently supporting inspections. Therefore, the consultation, including one hour of solar system planning and one hour of heating concept/insulation, costs a total of 50 euros. The city covers the remaining costs.