Hi, I have an electrical room to be installed a reverse acting thermostat, with setting point 100F. But I cannot find a reverse acting thermostat with 100F setting. H..Well product has only 86F. My design temperature outside is 87F in summer, so I want the setting to be 100F. Can anyone recommend a reverse acting thermostat for the electrical room (transformers load about 36000 BTU/h)?
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Reverse acting thermostat for electrical room
- Thread starter econ2016
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LittleInch
Petroleum
Not used them myself but a search found these...
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Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
In the industrial world, reverse action "calls for heat". I thought HVAC used the same terminology.
A reverse acting thermostat (heat controller) would attempt to maintain a setpoint of 86 Deg F by calling for heat until the sensor is satisfied at about 87 Deg F (deadband above and below the setpoint for on-off controllers).
Are you sure you want to maintain a temperature of 86 Deg F in an electrical room where devices are generating heat with a thermostat that calls for heat? You don't need a cooling thermostat?
If you'll notice, the list of applications for Little Inch's link, the Chromalox reverse acting controller/thermostat, includes water baths, heat sealers, and ovens; all heating devices, not cooling devices.
A reverse acting thermostat (heat controller) would attempt to maintain a setpoint of 86 Deg F by calling for heat until the sensor is satisfied at about 87 Deg F (deadband above and below the setpoint for on-off controllers).
Are you sure you want to maintain a temperature of 86 Deg F in an electrical room where devices are generating heat with a thermostat that calls for heat? You don't need a cooling thermostat?
If you'll notice, the list of applications for Little Inch's link, the Chromalox reverse acting controller/thermostat, includes water baths, heat sealers, and ovens; all heating devices, not cooling devices.
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- #5
My purpose is to start the exhaust fan when the reverse thermostat reaches 100F. then the room temperature will drop due to the outside air intake. Reverse t'stat will be interlocked with exhaust fan. I need some information regarding the reverse thermostat which will start the exhaust fan when T = 100F indoor.
LittleInch
Petroleum
Did you look at the links provided? they seem to fit the description.
What the thermostat controls is not relevant, it's just an open / close contact which in this case closes on rising temperature. What it controls is irrelevant to the thermostat - a switch is a switch. If the current capacity isn't big enough fit a relay or plug it into a breaker.
I'm struggling to understand your problem.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
What the thermostat controls is not relevant, it's just an open / close contact which in this case closes on rising temperature. What it controls is irrelevant to the thermostat - a switch is a switch. If the current capacity isn't big enough fit a relay or plug it into a breaker.
I'm struggling to understand your problem.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
- Thread starter
- #7
A heating thermostat calls for heat (closes relay contacts) when the sensed temperature drops (too cold: call for heat)
A cooling thermostat calls for cooling action (closes relay contacts) when the sensed temperature rises past the setpoint (too hot: call for cooling)
Close on rise is 'direct' action (industrial ISA world)
Close on drop is 'reverse'action
This is a cooling app which needs a cooling thermostat.
A cooling thermostat calls for cooling action (closes relay contacts) when the sensed temperature rises past the setpoint (too hot: call for cooling)
Close on rise is 'direct' action (industrial ISA world)
Close on drop is 'reverse'action
This is a cooling app which needs a cooling thermostat.
the chromalux site link in Little Inches post has both direct and revers acting thermostatic switches in the temperature range that you want ( 60-200 degrees F) here is the reverse acting part number ARR-219, the direct acting part number for the same switch is AR-219. These are what you need to turn a fan on when the temp rises. They are direct acting in that you do not need a switching relay you can wire them direct to the fan.
B.E.
You are judged not by what you know, but by what you can do.
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