# Interlock baseboard heaters and ac



## Confused_drew (Mar 12, 2018)

Killed at any moment dam auto correct


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## splatz (May 23, 2015)

Confused_drew said:


> I know its a supper easy cct it just makes my head hurt lol


You sure about that? I bet it isn't super simple.  

The thread title is different from your question, interlocking AC and heat isn't too difficult.


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## Peewee0413 (Oct 18, 2012)

Ya i see no simple circuit to share equal run time, at least not one Ricky Bobby HVAC can diagnose later down the road when something needs repaired. Series relays will only stop the use of more then 1. 4 more latching relays to disable a unit once it turns off, and a 9th can reset the circuits. What if someone opens a door for 20 minutes in the hot summer. It must wait its turn. Well then install a PLC add temperature sensing and program so the one furthest from the setpoint gets priority. How does someone screw up.. Put 1 source and 4 loads? Fix the real problem not add more stuff to cover it up...only an engineer would add more to cover up their mess up.

Sent from my VS995 using Tapatalk


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## Dennis Alwon (May 9, 2009)

What is the actual problem. Is the load tripping a main breaker?


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## Dennis Alwon (May 9, 2009)

I would think you can get a contact switch that is sp dt that will work on the low voltage side of the a/c units. 1st one to the second to the 3rd etc. 

I did this with a water heater by using a dt t- stat in the upper and lower portion of the first unit that in turn fed the second unit only after the first was satisfied.


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## splatz (May 23, 2015)

I think that would work if these were all running on the same zone, you could use an alternating relay, but an alternating relay that cycles between four loads might be more expensive than a PLC. 

I am thinking these are four separate units on four thermostats. 



Dennis Alwon said:


> I would think you can get a contact switch that is sp dt that will work on the low voltage side of the a/c units. 1st one to the second to the 3rd etc.
> 
> I did this with a water heater by using a dt t- stat in the upper and lower portion of the first unit that in turn fed the second unit only after the first was satisfied.


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## MechanicalDVR (Dec 29, 2007)

Need a little more info here Drew. Are you talking 4 split a/c systems, PTAK units, or what? 

What is the issue of only running one at a time?


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## splatz (May 23, 2015)

This is just messing around I wanted to see if draw.io would work for some ladder diagrams but this might be a start...


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## wildleg (Apr 12, 2009)

like mech said, you need to be way, way more specific about your loads and your power supply system deficiencies if you really want a solution (from here).

have you even consulted with a good hvac/control guy ? there are addon boards that can easily provide this function with run of the mill splits.


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## sbrn33 (Mar 15, 2007)

splatz said:


> This is just messing around I wanted to see if draw.io would work for some ladder diagrams but this might be a start...


You are smarter than me. 
I used to be as smart as you but as I got older I decided not to give a ****.


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## just the cowboy (Sep 4, 2013)

Buy a click PLC from automation direct. free software and if you buy the E-net model no special cables. This way you can sequence who gets to turn on.


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## splatz (May 23, 2015)

sbrn33 said:


> You are smarter than me.
> I used to be as smart as you but as I got older I decided not to give a ****.


I am not, but, I am working on giving less of a **** anyways  

Do you think the diagram would work?


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## JRaef (Mar 23, 2009)

Go buy a "quadraplex pump controller", meant to alternate the run time operation of 4 pumps. It will have secondary sequences to add "lag" pumps when necessary, you will want to disable that. You only want to use it as a "lead" alternator only.


http://www.dwyer-inst.com/Product/Level/PumpControllers/SeriesQPC
http://time-mark.com/shop/alternating-relays/d471/


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## splatz (May 23, 2015)

JRaef said:


> Go buy a "quadraplex pump controller", meant to alternate the run time operation of 4 pumps. It will have secondary sequences to add "lag" pumps when necessary, you will want to disable that. You only want to use it as a "lead" alternator only.
> 
> 
> http://www.dwyer-inst.com/Product/Level/PumpControllers/SeriesQPC
> http://time-mark.com/shop/alternating-relays/d471/


I thought of this too but I think lead / lag is usually for one set of floats, I think this has four thermostats.


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## splatz (May 23, 2015)

By the way the OP aside, draw.io that @macmikeman mentions now and then is pretty good for making ladder diagrams.


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## just the cowboy (Sep 4, 2013)

splatz said:


> Do you think the diagram would work?


Yes it would work but with first units getting priotity. With a little programming you could build a FIFO stack and load the unit requests in order.


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