Jan 12, 2005 12:48
19 yrs ago
3 viewers *
English term

thermostat off

English Tech/Engineering Mechanics / Mech Engineering
remote control system for an air conditioning plant (series of indoor units connected to some outdoor units)

The original English text may be incorrect as it is not written by a mothertongue and it is full of mistakes.

here are some sentences (not in sequence) where this expression appears:

"In order to increase continuous operation of the unit in low latent heat applications and avoid the rise
of temperature after thermostat OFF, the thermostat control will be changed when using field settings
....

To prevent the compressor from frequently turning ON and OFF and allow pressure equalization,
forced thermostat OFF will be conducted for 3 minutes after compressor stopping (compressor guard
timer).

Thermostat off due to freeze-up prevention

Thermostat off due to high outdoor temperature.

The thermostat control prevents the thermostat from turning OFF in the following conditions:
- Initial operation for the first 2.5 minutes, or
- Defrosting, or
- Forced operating mode

...I thought a thermostat would always stay ON, while it could turn ON/OFF the units based on the temperature reading, but here the thermostat appears to actually switch off.... or am I wrong?

Discussion

Non-ProZ.com Jan 12, 2005:
OK thanks Rahi this helps me understand! I knew it was a switch but did not stopped to consider this :-)
Non-ProZ.com Jan 12, 2005:
Thanks everybody, in particular as to Alaa's comments: many thanks for the explanation, OK I understand (broadly speaking) the mechanism by which the heat sensor switches off the compressor, but maybe my problem comes from the different meanings of the word "OFF", which if I translate as "spento" in Italian it means that there is no current through the device. So the sensor "informs" the thermostat that there is a need to switch off the compressor, but then the thermostat is ON (there is current through it) but will be kind of "Off line", not active, is that so? I still have some confusion

Responses

1 hr
Selected

switch

A thermostat is merely a switch and surely does trun on and off - based on a set of rules- whatever it has to turn on or off, be it a compressor, a damper actuator, whatever

--------------------------------------------------
Note added at 1 hr 4 mins (2005-01-12 13:52:23 GMT)
--------------------------------------------------

We also have humidistats, aquastats, and so on, all of them are swtiches that operate in certain conditions and response to certain variables like temperature, humidity, water level ,....

--------------------------------------------------
Note added at 2 hrs 8 mins (2005-01-12 14:56:57 GMT)
--------------------------------------------------

Ever noticed the floater mechanism in the toilet flush? that\'s a switch too, if the water lever in the tank is low, the floater shall open the (Turn ON)stream and allow water into the tank, when it reaches a certain predefined level, it stops (Turns OFF) the water flow.

A thermostat operates based on a very similar concept.
Something went wrong...
4 KudoZ points awarded for this answer. Comment: "many thanks, thanks alos to Alaa, I would like to split points between you too but it's not possible"
+2
10 mins

thermostat off...

:) ...means it does not activate the compressor (turning on the system and changing the temperature)

--------------------------------------------------
Note added at 12 mins (2005-01-12 13:00:01 GMT)
--------------------------------------------------

Nothing technically wrong in the text
Peer comment(s):

agree RHELLER : deactivated
3 hrs
thanks
agree Alfa Trans (X)
6 hrs
thanks
Something went wrong...
13 mins

>>>>

OFF – position when the thermostat does not work
ON – the devise works
Something went wrong...
37 mins

how the thermostat is turned off

The thermostat is turned off by one of two mechanisms:

- The heat sensor (or old-fashioned metalic coil) detects the temperature falling below the required temperature. A circuit is opened and the compressor is switched off.

- Programmed or manual override forcing the thermostat into the above condition, either permanently or temporarily.

The above text list the conditions under which the second mechanisms overrides the heat sensing mechanism to force the thermostat into the OFF state, or to prevent the OFF state from kicking in.

Hope this helps


--------------------------------------------------
Note added at 44 mins (2005-01-12 13:32:06 GMT)
--------------------------------------------------

Temperature sensor is a little more accurate than heat sensor in the above explanation.

--------------------------------------------------
Note added at 1 hr 30 mins (2005-01-12 14:18:03 GMT)
--------------------------------------------------

In answer to your follow up question:

You think the text uses thermostat OFF in two ways, either the thermostat switches off normally, or the thermostate is disabled. I do not think that is the case. I believe that the word simply means that the thermostat (the switch as Maya and Rahi indicated) is put in the OFF position, by any means, for example:

1. Surrounding temperature sensing
2. Timed, as during initialization of the system, or for several minutes following (1.) to prevent thrashing back and forth, etc.
3. Forced, as in the case of high outside temperature, probably to prevent continuous operation

I believe that you interpreting into the text two different modes: ON/OFF and enable/disable. You may be right, but I do not think so. I lean to read the OFF in this text as the OFF position throughout the text, but I could be wrong too!

--------------------------------------------------
Note added at 1 hr 33 mins (2005-01-12 14:21:17 GMT)
--------------------------------------------------

I said (as Maya and Rahi indicated). Actually Maya describes a \"diable\'\" action, so I should only say (as Rahi indicated).
Something went wrong...
1 day 20 hrs

thermostat is switched off from the control circuit.

thermostat is switched off from the control circuit.
Something went wrong...
Term search
  • All of ProZ.com
  • Term search
  • Jobs
  • Forums
  • Multiple search