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Nov
27
comment Blower fan speed selection
In North America it is rare that residential HVAC systems are rigorously designed. You shouldn't equate what is customarily installed and configured by HVAC technicians as being correct or optimal. Case in point: The dynamic range of motor speeds available in a typical residential furnace is too small to achieve the optimal speed for the full range of conditions. You'd need a variable frequency drive to achieve that (I've retrofitted these), but they are expensive so residential equipment generally just uses the crude relays-and-windings method of speed control.
Nov
19
comment How to attach metal knife rack to tile without ruining tile?
Exactly. Here's a 1/4" diameter example. Here's a 3/16" example. It's the only thing I use for drilling mounted tile. I've cracked tile with pointed bits; never with a hole saw.
Nov
19
comment How to attach metal knife rack to tile without ruining tile?
IME small diamond hole saws are less likely to crack tile. They distribute the drilling stress over a wider area and require less material to be removed.
Sep
21
comment Is this swing beam safe?
The deflection or strain is not what you should be worried about. Rather, you should be worried about catastrophic failure of your structure which can occur even without visible strain. In other words, deflection is not a good indication of impending structural failure at all.
Sep
21
comment Is this swing beam safe?
Those "standard load calculations" you are using are almost certainly for a static load and aren't applicable to the dynamic loading that a person on a swing would subject the beam to. Tables for dynamic load must exist somewhere for there are plenty of wooden bridges that support the dynamic load of cars crossing. The static load calculations you used, however, won't tell you much about failure under dynamic load.
Sep
3
comment Home security sensor for windows
Answer: You need magnetic contact switches mounted such that they detect whether the windows and/or louvres are open or closed. That way your alarm panel can enforce that they are closed. Judging from the picture you'll probably have the best luck with this surface-mount style contact.
Jun
10
comment Vibration dampening solution to stop extractor fan / dishwasher vibration?
Based on your description, I don't think there is a practical way to isolate your bed from the vibrations. It is notoriously difficult to isolate a room from low frequencies. This is why physics labs and recording studios are often built on massive concrete floors at or below grade; they rely on the overwhelming inertia of the floor to prevent vibrations from transmitting through it. Because the mass of all floors except the bottom has to be supported by the building's structure, they tend to be light enough that equipment can transmit small amplitude vibrations into them.
Jun
10
comment Vibration dampening solution to stop extractor fan / dishwasher vibration?
Is your bed in the middle of a large unsupported span of floor? Floor-joists in wood-framed buildings have vibration properties similar to guitar strings -- they have a resonant frequency, and the further you are from the support structure, the larger the amplitude of the vibration. The last building I lived in had a section of floor with a very noticeable 5 to 10 Hz resonant frequency. The washer would induce vibrations. The point is, if you move your bed adjacent the walls that support the floor, the amplitude should be smaller.
Jun
10
comment Vibration dampening solution to stop extractor fan / dishwasher vibration?
That's pretty low frequency to isolate using mass-on-a-spring isolation. The springs would be rather large and expensive. You'd also need damping if you went that route because you'd have a natural frequency in the single-digit Hz range that you'd excite just getting into bed.
Jun
8
comment Vibration dampening solution to stop extractor fan / dishwasher vibration?
You say it's not audible. How, exactly, does it disturb your sleep? Do you feel it? What does it feel like? Like being aboard a ship? Or more like riding a bus on an uneven road? To determine whether it's practical to do something about it, it's important to determine the frequency of the vibration.
May
29
comment What is difference between BTU and MBH for house furnaces?
mille or mil means thousand in at least French, Italian, Portuguese, and Spanish.
Sep
8
comment How can I run Ethernet cabling through concrete walls?
"Concrete walls typically have conduits where all wiring passes." There is a lot of construction where electrical cables are cast into concrete without conduit. I think that statement is rather misleading.
Sep
8
comment How do I fix this leaking dishwasher drain pipe?
A picture of the problematic hose would really help narrow down the possible solutions.
Jul
10
comment How can I consolidate different heating/cooling systems into a single system?
You could probably configure a unified controller using gear from Easy IO. I haven't used that brand myself (but have come close), but it has been recommended to me by an industrial HVAC engineer as "can control anything, easy to program, and reasonably priced."
Jun
6
comment How can I add a “C” wire to my thermostat?
@BMitch Incorporated the suggested edit.
Feb
15
comment Can a wet vac be effectively used as a pump?
...and if you're trying to siphon a basement, it won't work because you'll have negative hydraulic head.
Feb
14
comment What should I look for when diagnosing electrical circuit gremlins where load is much less than capacity?
you're welcome.
Jan
31
comment How can I stop exhaust fan vent condensation problems?
@bcworkz :) I don't want belabor the (dew) point. But dew point actually has a concrete definition. It is defined as the temperature below which condensation occurs, and is given in degrees C or F. So the higher the RH the lower the dew point, not higher as you say in your comment and imply in your answer. (All puns intended.)
Jan
28
comment How can I stop exhaust fan vent condensation problems?
+1 Although I think you meant either "bathroom exhaust has a very low dew point" or "bathroom exhaust has a very high relative humidity".
Jan
24
comment What could be causing this leaky evaporator problem?
"do you think he is on the right track?" is a pretty vague question to answer. "Do you think this is part of the problem?" makes me wonder what, exactly, you mean by "this". I'm pretty sure somebody here can give you help, but it will be much easier for everyone if you could focus your question(s).