ᐅ Underfloor Heating Heat Load Calculation – Explained Simply
Created on: 3 Dec 2020 13:36
H
Hamburger2020
Good day,
I have read many posts on this topic and have so far understood that room-by-room control (RBC) is no longer necessary nowadays, as it reduces the efficiency of the heat pump.
We have a ground-source heat pump with underfloor heating in all rooms.
The goal is to perform a room-specific heating load calculation so that the temperature is properly set once and never adjusted again.
Our general contractor (GC) now argued that while this is basically correct, once people reach their 60s or older and develop different habits regarding room temperatures, it is not so easy to adjust. Therefore, their suggestion is not to optimize for the highest efficiency right now but to maintain some flexibility through RBC.
I think this argument should not be underestimated. However, I suspect that with the "modern" method of a maximally efficient heating system, this might also be possible.
How would you respond to the GC on this?
Thank you very much and best regards
I have read many posts on this topic and have so far understood that room-by-room control (RBC) is no longer necessary nowadays, as it reduces the efficiency of the heat pump.
We have a ground-source heat pump with underfloor heating in all rooms.
The goal is to perform a room-specific heating load calculation so that the temperature is properly set once and never adjusted again.
Our general contractor (GC) now argued that while this is basically correct, once people reach their 60s or older and develop different habits regarding room temperatures, it is not so easy to adjust. Therefore, their suggestion is not to optimize for the highest efficiency right now but to maintain some flexibility through RBC.
I think this argument should not be underestimated. However, I suspect that with the "modern" method of a maximally efficient heating system, this might also be possible.
How would you respond to the GC on this?
Thank you very much and best regards
S
Sparfuchs778 Dec 2020 13:12lesmue79 schrieb:
The house is located in the Westerwald, where winters used to be quite cold (down to -12°C to -15°C (10°F to 5°F)). The calculated heating load for 100m² (1,076 sq ft) of living space is just under 3.5 kW. For comparison, since I’d like to address some of your other points:
- we built according to the Energy Saving Ordinance and, according to the calculation, have a heating load of just under 6 kW for 170m² (1,830 sq ft). Underfloor heating with a gas boiler. The plan was for 24cm (9.5 inches) of sand-lime brick plus 16cm (6.3 inches) of external thermal insulation composite system (ETICS) with a thermal conductivity of 0.035 W/(m·K). We actually installed ETICS with 0.032 W/(m·K).
lesmue79 schrieb:
Forget about having 24°C (75°F) in the bathroom and just 18°C (64°F) in the bedroom right next to it—you will get a maximum temperature difference of about 2°C (3.6°F) between rooms, if any at all. Is that because of the heat pump? We have the heating set to level 3 in the bedroom, which results in about 18°C (64°F), while the adjacent children’s room is 22°C (72°F) during the day and 19°C (66°F) at night.
lesmue79 schrieb:
Underfloor heating designed for a maximum supply temperature of 30°C (86°F) according to the lowest expected outdoor temperature (NAT)… not 35°C (95°F). NAT = lowest expected outdoor temperature? Ours is -13°C (9°F). Do I understand correctly that, with an outdoor temperature of -13°C (9°F), a supply temperature of 30°C (86°F) keeps the house comfortable? (22°C (72°F) in living rooms and 24°C (75°F) in the bathroom?) At -4°C (25°F) outside, my boiler already runs at 37°C (99°F).
S
Sparfuchs778 Dec 2020 13:19Mycraft schrieb:
Gas boilers respond faster and can practically operate at higher flow temperatures without significant changes in consumption. It’s somewhat different with heat pumps. Ok, sorry. I didn’t mean to hijack the thread. I might start a separate thread about this later. Thanks anyway.
Does anyone know if a building owner has a legal right to receive the heating load calculation? We are building with a general contractor and have not received anything like that. We are simply being provided with a heating system of a certain capacity. However, its capacity is included in the energy performance certificate.
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nordanney13 Dec 2020 21:04Hausbaer schrieb:
Does anyone know if a property owner has a legal right to receive the heating load calculation? We are building with a general contractor and did not get something like that. We are simply being provided with a heating system of a certain capacity. However, its capacity is included in the energy performance certificate.It depends on when you signed the contract. From 01.01.2018 onwards, you have a right to it.Similar topics