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Discussion Starter #3 (Edited)
UPDATE: Aprilaire support told me to wire the G wire in series.

In other words, G from thermostat must go to G on the 60 control. Gf on 60 control must go to Gh on the dehumidifier. Gs on the dehumidifier must go to G on the furnace.

Proper wiring diagram:
 

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On your first schematic, there was a possibility of an undesirable backfeed when the fan (G) circuit would be energized by one of your humidity altering units and it would cause the condenser unit for cooling to start since some thermostats have the Y leg and the G leg tied together in the cool mode.

Alprilaire advised wiring the G and Y separating function of each device in series so either of your units can accomplish it.

You should be good to go now.
 

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Discussion Starter #5
2nd Update! First two pictures are incorrect. Aprilaire support just wrote back again and said this:

My apologies, I accidently mixed up the Gs and Gh wiring of the dehumidifier.

You must have Gf from the 60 control going to Gs on the dehumidifier. You must also have Gh from dehumidifier going to G on the furnace.


Here is hopefully the final wiring diagram of a Thermostat, Humidistat, Dehumidifier, and Humidifier all tied together.
 

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I'm not getting the logic of the series wiring (probably me being dense). If the Gf output of the model 60 goes to the Gs input on the dehumidifier and dehum terminal Gh powers up the furnace fan, how is power delivered to the Gs input on the dehumidifier if the humidistat is not calling for humidity? Not saying Aprilaire is wrong, I just don't see how it would work.
 

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Discussion Starter #7
All is working as far as summer goes. They way they had me wire it the dehumidifier 1850 will turn the furnace blower on when air sampling and dehumidifying.

What I can tell you is currently the Aprilaire model 60 Humidistat is turn off because it is summer. This must be just passing on GF to G.

What I am getting out of this is either device when not calling for humidity or humidity just passes the signal on via a dry contact. G to Gf, and also Gs to Gh. But in winter mode if humidity is needed beyond the heat cycle it send out signal via Gf. In Summer mode I assume if the dehumidifier needs to work beyond the cooling cycle it turns on the Gh. All other times the signal is just passed on.

This is just my theory since it is working fine at the moment.
 

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Your theory makes sense to me, the contacts would have to be closed when the device is off or the furnace fan wouldn't run for a/c. Good to learn something new. Makes me wonder if your original parallel method wasn't viable too.
 

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Discussion Starter #9
57TinkerMan I wonder too. I did want to share something Aprilaire just confirmed for me.

I am not crazy about the Aprilaire 1850 Dehumidifier each hour sampling the air, but I know it has to. So I got thinking maybe add a Humidity sensor in the living area, and also still have the 1850 be able to turn on the Furnace blower when it needs to dehumidify.

Aprilaire wrote back that this will work as long as I wire it like I sent them and I use a dry contact control like Aprilaire model 76 or similar. AND program the 1850 for EXTERNAL CONTROL. (not remote control)

I will be using and just ordered a Honeywell HumidiPRO Digital Humidistat/Dehumidistat Humidity Control model H6062A1000 just because I like the looks of this one over the aprilaire 76. Both use dry contacts to turn the dehumidifier on.

Here is my final wiring approved by Aprilaire.

Also note, A technician who thinks they know everything, will never learn new stuff. I have been a technician for 40 years and every day I learn something new. Share, Share, Share. Today I learned more about HVAC stuff then I thought I need. :smile:
 

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Not sure if you are planning to have both units controlled by one device, if so, the Honeywell Humidpro that you mentioned will only control one unit either a humidifier or dehumidifier not both. The control I mentioned in my first post will control both if that's your intention. About the same money too.
 

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I'm not getting the logic of the series wiring (probably me being dense). If the Gf output of the model 60 goes to the Gs input on the dehumidifier and dehum terminal Gh powers up the furnace fan, how is power delivered to the Gs input on the dehumidifier if the humidistat is not calling for humidity? Not saying Aprilaire is wrong, I just don't see how it would work.
Here's something that may help.

The reason for having the G leg run through these devices on its way from the thermostat to the furnace is to remove undesirable backfeed to the thermostat when one of these devices energizes the G leg to turn on the furnace blower. That is necessary because some thermostats have the Y leg connected to the G leg permanently. If the backfeed path to the thermostat was left in place, then energizing the G leg would also turn on the condensing unit via the Y leg. To prevent that, Aprilaire provides the internal switching to disconnect the G leg from the thermostat as it energizes it's own specific operation.

Using 2 control devices makes it necessary to have that "backfeed disconnect operation in series so that whichever unit energizes the G, the series path back to the thermostat will be opened. That gives each unit full control of the backfeed disconnecting process. That obviously would not work if you had it wired in parallel, as was first diagrammed, since one of the switches would always be closed (they are NC when the device is idle) rendering the other switch actions ineffective.

I hope I have explained that in a way to be helpful. It would be much easier to understand if Aprilaire would publish an internal diagrams for their devices but alas, I have never been able to find any for their products. They do seem to make it difficult for lots of people to install their products, pros and DIY'er alike.

As Aprilaire realized when they saw their error, polarity is important on the sequence of the series loop for obvious reasons. The flow must always be from the s to the f tagged terminals.
 

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Thanks for the refresher. This for me is a generational thing, I didn't play around much with the newer "stuff". I'm much more comfortable with the old electro-mechanical devices. That's why I like to peruse the forums, keeps me somewhat up to date on the technology. I'm sure I'll reach my technological saturation point all too soon.:sad:
 

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T I'm sure I'll reach my technological saturation point all too soon.:sad:
:vs_laugh: I reached mine years ago!! :devil3:

You're doing alright as long as you know what you don't know and how/where to get it when needed. If Google and Youtube had been around a little sooner, I could have had a little easier go of it... it was hard wingin' it back in the 60's. :wink2:

All the best, SD2
 

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Discussion Starter #14
Thank you surferdude2 for the information. Now this makes a lot more sense to me. ( that bit of information should be in the installation manual).:wink2:

57TinkerMan I am not planning to use one control for both. The Aprilaire model 60 does a great job for humidity. I will keep it as in the diagram and add the new Honeywell HumidiPRO as a Dehumidistat.

Thanks everyone for a great learning experience. :eek:nline2long:
 
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