Timeline for Physics of heating a swimming pool
Current License: CC BY-SA 3.0
10 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 7, 2016 at 7:31 | comment | added | Walter | @DJohnM All the boiler does is heat its water (not that in the pool) from the temperature in pipe B to that in pipe A (which is always 180 degrees). Surely, this depends on the temperature in pipe B. If that is already 180 degrees, the boiler has nothing to do. | |
| Jun 6, 2016 at 22:05 | comment | added | DJohnM | @Walter Under the assumptions in place at the time of my answer (continuous operation of boiler until target temp is reached), how can the heat transferred from the boiler not be constant? | |
| Jun 6, 2016 at 20:16 | comment | added | sammy gerbil | There's a bit too much "exploding" and "blowing up" going on here for my liking! | |
| Jun 6, 2016 at 20:15 | comment | added | Walter | This is plainly wrong. Set the flow rate to 0 and nothing will ever happen, except the boiler will switch off. The point is that the heat input by the boiler does also depend on the backflow temperature, not just on the input temperature. | |
| Jun 6, 2016 at 19:48 | comment | added | DJohnM | Oh... Yes, by all means add that... The boiler shuts off if the output goes above 180? | |
| Jun 6, 2016 at 19:02 | comment | added | WillO | The water arriving from the boiler is kept at a fixed 180 degrees. Perhaps I should add this clarification to the question. | |
| Jun 6, 2016 at 18:56 | comment | added | DJohnM | From the OP, I thought that the boiler could run full time until the pool warmed up. If not, you need a bigger transfer loop to minimize warm-up time... | |
| Jun 6, 2016 at 18:52 | comment | added | WillO | (CONTINUED) So your italicized sentence in the first paragraph can't be true at low flow rates, and the reason it's not true is that the boiler does not have a fixed rate of heat energy production --- it kicks on and off as needed. If your statement is true at high flow rates, then what is the key unstated assumption that prevents your logic from applying at low flow rates? | |
| Jun 6, 2016 at 18:50 | comment | added | WillO | I do not quite understand this. Suppose I turn off the flow of water from the pool entirely. Then the boiler water comes out at 180 degrees and returns to the boiler at 180 degrees, so (assuming an ideal system), the boiler never needs to kick on. At the same time, the pool never heats. Now if I go to a small positive flow rate for the pool water, heat is transferred to the pool water, the boiler water leaves at 180 and comes back at (say) 170, and the boiler kicks on and off just enough to make up this difference. Now the pool heats a little. (CONTINUED) | |
| Jun 6, 2016 at 18:29 | history | answered | DJohnM | CC BY-SA 3.0 |