ᐅ Automation of a Mechanical Ventilation with Heat Recovery (MVHR) System
Created on: 23 May 2018 17:44
H
Hausbauer1
Hello everyone,
I’m currently struggling again with the warm indoor temperatures (unfortunately, there is no mechanical ventilation with heat recovery). When I am at home, I try to ventilate vigorously whenever it is cooler outside than inside, even if the temperature difference is only 1-2°C (34-36°F). And when it’s warmer outside, everything is shaded and the windows stay closed.
This obviously pushes comfort limits. If you want to stay in a room, ventilating at the same time is not always very comfortable. Also, you don’t want to leave the windows open all day when you’re not at home or when it gets warmer as the day goes on.
My question to all experts and owners of centralized ventilation systems is: can a mechanical ventilation system be programmed to operate exactly like the rational ventilation behavior you would do manually? So, no ventilation when it’s warmer outside and strong ventilation when it’s cooler outside. Of course, without heat recovery in this case. In winter, it would be different, with ventilation mainly during the day when temperature differences are smaller, and less or no ventilation at night when it’s very cold outside.
I think it’s clear what I’m getting at. Can these systems be automated to that extent, or is that too much to expect?
Thanks.
I’m currently struggling again with the warm indoor temperatures (unfortunately, there is no mechanical ventilation with heat recovery). When I am at home, I try to ventilate vigorously whenever it is cooler outside than inside, even if the temperature difference is only 1-2°C (34-36°F). And when it’s warmer outside, everything is shaded and the windows stay closed.
This obviously pushes comfort limits. If you want to stay in a room, ventilating at the same time is not always very comfortable. Also, you don’t want to leave the windows open all day when you’re not at home or when it gets warmer as the day goes on.
My question to all experts and owners of centralized ventilation systems is: can a mechanical ventilation system be programmed to operate exactly like the rational ventilation behavior you would do manually? So, no ventilation when it’s warmer outside and strong ventilation when it’s cooler outside. Of course, without heat recovery in this case. In winter, it would be different, with ventilation mainly during the day when temperature differences are smaller, and less or no ventilation at night when it’s very cold outside.
I think it’s clear what I’m getting at. Can these systems be automated to that extent, or is that too much to expect?
Thanks.
Well, in the office, thanks to the PC and 3 monitors, it’s a comfortable 24°C (75°F) right on time for the 10 a.m. break. By 3 p.m., it reaches 25–26°C (77–79°F).
In the rest of the house, the temperature remains steady at 22–23°C (72–73°F) thanks to automated shading and the summer bypass of the controlled residential ventilation system.
In the master bedroom area, it’s even a bit cooler.
In the rest of the house, the temperature remains steady at 22–23°C (72–73°F) thanks to automated shading and the summer bypass of the controlled residential ventilation system.
In the master bedroom area, it’s even a bit cooler.
D
Deliverer6 Jun 2018 13:55matte1987 schrieb:
What really bothers me is the power consumption in standby mode. The indoor units are powered by the outdoor unit, which is connected to a KNX power meter actuator.
I happened to discover that the system draws about 45W in standby!
That adds up to roughly 1.1 kWh per day, or about 10% of our total energy consumption. Something doesn’t seem right there. Oil sump heaters only activate when it’s really cold outside. On most units, you can also disable them (using pins on the outdoor unit) if you don’t intend to use the system for heating.
My (Mitsubishi) system has its own electricity meter, and it hasn’t registered any usage during months when the system wasn’t in use. (Although it only measures in 0.1 kWh increments, that should be sufficient.)
On the other hand, I’m quite pleasantly surprised by the electricity consumption: The standalone system operates in an older building with 140 m² (1506 sq ft) all on one floor, half of which extends up to the roof, and with all doors open. Last week, it ran daily from noon to midnight, with outdoor temperatures between 28-30°C (82-86°F) and an indoor temperature of 24°C (75°F), costing me about 9 euros. In my opinion, that’s a bargain for the comfort it provides. We sleep well, don’t have to ventilate as much at night (noise and pollen can be annoying), and I don’t have to think twice about turning on the computer or cooking a meal in the oven.