Recent content by TSN79

So the pump setting might eliminate the whole issue? Worst case is that the pump is constant speed only. If an apartment was to get some overflow - would the reasoning about faster heating hold at all?

The temperature is controlled by room thermostats that open and close actuators (on/off) on the manifold. I'm not sure how the pump is controlled. My best guess is that it keeps a constant pressure - so I do believe it reduces rpm as head loss increases when most actuators close.

Several apartments have under floor heating (water) with a common boiler room and a central pump. There is no pump in the apartments. Each pipe run on each apartment's manifold has its own flow-indicator. The owner of one apartment is worried that if the neighbor turns off its heating, then more...

An apartment has a radiator, about 1000 W. Nearly right above it is an extract valve for the ventilation system which extracts 35 m3/h. The vertical distance between the two is around two meters. Is there a risk that this will prevent the radiator from functioning properly as the hot air will...

I read somewhere that it matters if I "own" the shared folder or not. If I don't, then all I do is delete my copy of the file. But if I do then I'll delete it for everybody. Does that sound right?

I'm often involved in projects where Dropbox is used to share documents, and members are invited in order to gain access to a folder established by one of the members (not me). I recently got a message that my Dropbox quota (2 GB) is us up. I don't sync anything locally, I only use the documents...

My city has large district heating system, where the heat is generated at an incineration plant. I'm personally not a fan of district heating, and I would rather see the plant generate electricity through steam instead. I don't know if that was ever considered when the plant was built. Are there...

I was watching a game of snooker, and sometimes the cue ball bounces off the cushions with surprisingly high speed. Some people often say that it comes off the cushion faster than it went into it. And I started thinking - is that even possible? Does physics work that way?

Picture two water heaters - one 10 liters and the other 100 liters, initially filled with cold water. If both of them are heated to the same temperature, will a pressure meter display the same pressure for both tanks, or is the resulting pressure somehow dependent on the size of the tank?

In this case there actually shouldn't be any other path available. The machinery sits in a room which has a wall that also has it's requirements regarding sound transfer. The only open path through the wall is the duct on which I plan to install the silencer(s).

Consider a straight duct silencer of any sort. If you place two of them in series, how will that affect the sound? If one silencer results in a 10 dB reduction for a specific frequency, will using two result in 20? It just seems like too much of an easy answer so I thought I would check with...

Not really, but that kind of information has gone into a calculation that sombody else has already done, resulting in a total energy need over a year (for room heating) of about 80 000 kWh.

A building needs a certain amount of energy during a year (kWh) for room heating. An air to water heat pump has been installed to provide heat to a radiator system (55/40°C). How do I go about estimating how much of the yearly energy need the heat pump will cover? What confuses me is that the...

My beard looks all blond to begin with, but for some reason it looks darker as it gets longer. Why is that?

The sprinkler valve represents the beginning of the system, and is also where the residual pressure is measured. Let's say point Pa represents this location. Once there is flow, the pressure reading at Pa will start to fall. Is there a need for Pa not to fall below 3 bars (if the calculated loss...