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Daniel Plourde
Daniel Plourde, HVAC Technician
Category: HVAC
Satisfied Customers: 251
Experience:  hvac technichian at performance plumbing and heating
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I have recently had installed your 2E728 ventilation control

Customer Question

I have recently had installed your 2E728 ventilation control in my greenhouse. The fan only works when the control is less than 30 degrees. When I turn the knob to a higher number the fan shuts down. There must be an adjustment that I can make in order for the fan to turn on and off . This my second message to you.
Submitted: 4 months ago.
Category: HVAC
Expert:  Daniel Plourde replied 4 months ago.

hi i am dan i can help you with this. is it a new control or existing? what is the temperature it is sensing?

Customer: replied 4 months ago.
The control was just installed and has never been used before, therefore I consider it new, but I have had it in its box for several years.
The greenhouse exhaust fan turns on when the control reads less than 30. IE: when the dial has been turned to the extreme left. When I turn the knob to the right and the temperature numbers start to go higher, then the fan shuts off. I assume there must be an adjustment some place on the unit in order to set the dial at the required temp. and it will then turn on and off accordingly.Bruce.
Expert:  Daniel Plourde replied 4 months ago.

ok what terminals do you have in the control and which ones do you have the wires connected to?

Customer: replied 4 months ago.
The electrician did it, I have no idea. Do you want me to do something?
Expert:  Daniel Plourde replied 4 months ago.

i would pull the cover off and check the wires. make sure the power is off first. if there are three terminals they will be labled as C, NC, NO. you want the wires on C and NO

Customer: replied 4 months ago.
Please tell me where the wires should be connected. I can't understand if the fan works, why doesn't the controller? I think the same wire (black ?) comes and goes through the controller (?)
Expert:  Daniel Plourde replied 4 months ago.

as i said the wires should be connected to C and NO are there 3 or 2 terminals in the control?

Customer: replied 4 months ago.
Can you send me a wiring diagram since one was not in the box with the controller and the electrician had to work his way through on his own?
Expert:  Daniel Plourde replied 4 months ago.

this is a very simple switch. there is no wiring diagram. are there 2 terminals or 3 terminals?

Customer: replied 4 months ago.
There are 2 terminals. Today I reversed them and had no change in its operation. Plan to go to an electrical store for them to examine the controller. The problem remains the same.Bruce Hausser
Expert:  Daniel Plourde replied 4 months ago.
Ok if there are only 2 then it is just a single pole switch. That means that it is bad. It relies on the pressure of the refrigerant in the bulb to operate the switch based on temperature. Since it only works at 30* that means the bulb has list its pressure and it leaked out somewhere. The switch will have to be replaced
Customer: replied 4 months ago.
what is the next available control that you would recommend as a replacement and how much would it cost?
Expert:  Daniel Plourde replied 4 months ago.
Any line voltage cooling thermostat will work as long as it is rated for the lra ratting of the motor. They usually cost anywhere from $15 to $50
Expert:  Daniel Plourde replied 4 months ago.
If you have any more questions about this please let me know. If not I would appreciate it if you could rate me on my service by selecting one of the 5 stars. And thank you for using just answer
Expert:  Daniel Plourde replied 4 months ago.

did you have any more questions about this or did I answer everything for you?