Chasing a HVAC controller that is easy to operate!!!

[jmcnaught]

I have been frustrated by the seeming lack of HVAC controllers which are easy to program and straight forward to use.
I am chasing something with a 7 day timer, which can operate a relatively simple setup of a couple of split AC units.
I am in the design field, and have had a number of clients say the controllers are too hard to use, but we have been unable to source any which do the job any easier.
Anyone with experience in this who has found something which works - I would love to hear from you.

 

[stoov1]

I am going to take this thread one step further. I am looking for an inexpensive controller to handle a small split system with a modulating steam coil. I understand (and agree with)the comments about not allowing everybody to manipulate the controls but this was not the intent of the original query. The fact is that the manufacturer's have not adequatly filled this need. They have jumped from pneumatic controls into DDC without adressing application for simple and less complicated controllers. I would greatly appreciate information on a simple stand alone controller that can be programmable for the operation of a 5 ton split system and provide MODULATING control of a steam reheat coil. I have had no luck. What is happening is that a $4,000 HVAC system is requiring $4200 in DDC controls. I have talked with JCI, Trane, and Honywell with no luck. Any info on this would be a great help. Thanks.

 

[jmcnaught]

Stoov1,
This is a very similar problem to the one I encountered. It is the modulating controls that are difficult to have in a small system. Maybe I was too general in my initial outline.
Also, the ability for the client to operate the system easily is important in this case, although I realise in most cases the above comments are correct.
Will approach the above companies and see if they can help. (Have already questioned Hevac, Honeywell & Trane to no avail).
Jmac.

 

[ClydeMule]

JMC,

I am not quite sure what you mean by "programmable." If it means a device that is programmed by setting a large nuimber of parameters, then I can't help you. Sorry. However, if you are looking for a controller like a PLC, that ships to you totally blank (does nothing when you plug it in), then I would recommend looking at CAREL. They have a controller called the PCO (pico) that comes in a variety of configurations, that can be programmed to do whatever you want. The programming is a little tricky, it is a graphical programming interface, but quite different from standard ladder relay logic. All of the PCO come with Analog and Digital I/O. Your garden variety PLC only come with Analog I/O at a premium price. THey also manufacture a wide range of temperature, pressure, and humidity probes, as well as fan speed controllers. There are built in functions for calculating wb and DP temps, and other HVAC calcs. The analog outputs are 0-10 VDC for controlling a valve, or you can get ones with an SSR output.

If you have to program it yourself, then you have to buy the software. That will make it expensive. But if this is something you can ujse more than once, then the one time expense is worth it.

I have used and programmed many of these controllers and have not come up against any HVAC application where I could not use this controller.

Check out

http://www.carel.com

or

http://www.carelusa.com

Hope this helps.

Clyde

 

[cooltec]

Check out this controller from Com-Trol. I have worked in the supermarket field of HVAC/R for sometime and we use this extensively. It can also control your lighting, alarms and monitoring runtimes, maintainence, ect.

http://www.ies.invensys.com/pdf/MCS-4000.pdf

I have used it for years with very good results.

 

[wj33]

Try

http://www.viconics.com/