wifi honeywell thermostat control unit

[paulga]

Thats a conundrum.
It's 24v powered relay logic. The relays have a diagram on top. I'm assuming powered closed.
So if closed they are getting 24v.
Verify your meter settings and retest.

I think you are referring to the relay box on the top right corner. It looks similar to this ac contactor but does not have diagram printed on top.

If the air conditioner is working, should there be 24v b/t the red and green terminals outside of the control box?

 

[Turtle Blues]

Green outside the control box is fan. Red is 24vac. Jumping them together should energize fan. You will not get a voltage reading between them as you are at 2 points on the same side of the control loop. The other side is at the relay in the cabinet.

 

[Turtle Blues]

If a relay is pulled in you might get a voltage reading because it is seeing through the relay.

 

[Bmarler]

Use the ac setting on your meter Jay, not dc. It’s 24 volts ac coming off the transformer.

 

[paulga]

Green outside the control box is fan. Red is 24vac. Jumping them together should energize fan. You will not get a voltage reading between them as you are at 2 points on the same side of the control loop. The other side is at the relay in the cabinet.

Per suggestion from @Bmarler I tested the voltage again and got 26.5vac b/t the green common wire and the R terminal. I was prejudiced by the safe and low voltage level thinking it was dc.

The green wire is attached together with a yellow wire to the relay box using a 3 way quick disconnector. Is it common practice to add a second 3 way quick disconnector in order to add the C wire?

 

[Bmarler]

In that particular box I’d say anything goes. It won’t hurt to add another splitter.
Personally, I’d be embarrassed to say I built that. Oh well, it probably looks fine with the lid on.

 

[Turtle Blues]

Ouch, that was just hurtful.
I'm the dinosaur that remembers when it was state of the art.
That box was assembled by a human, standing at a workbench, in Florida, in a building without AC. Long before pressed circuit boards took over the industry.
OP will be able to add a wifi stat for about $100.
A micro air wifi stat and compatible board to retrofit current products will run about 8 boat bucks.
So much for digital circuitry making products less expensive.

 

[Bmarler]

My wife and I build industrial control equipment. So we are certainly up to speed on best practice when it comes to wiring a panel.
I didn’t mean to offend with that comment, and am very apologetic if offense was taken.

 

[paulga]

In that particular box I’d say anything goes. It won’t hurt to add another splitter.
Personally, I’d be embarrassed to say I built that. Oh well, it probably looks fine with the lid on.

Thanks. now i'm clear what to do.
we are looking at a control box that was made at least a decade ago. i'm sure nowadays their internal design has become more simplified and organized

 

[Turtle Blues]

No, no offense taken. My attempt at humor did not come off as intended.
Hopefully we have sorted through the wiring to the point that OP can get his wifi stat operational at a fraction of the cost. Hoping that this R22 unit still has some life left in it.

 

[Bmarler]

I’m still running an r22 unit too. It came uninstalled with the boat when we purchased it.
I did a temp install thinking I’d replace it in a year or so, but it just won’t die…

 

[paulga]

Hmm, I can't say yes to your question, looking at your photo neither wire goes to the stat base uninterrupted, but that doesn't matter. Verify with a meter that the red wire is what eventually lands on the R terminal on the base.
Green landed on the stat base according to standard color coding would be the fan.
The module you have above is intended to save you from having to pull an additional wire.
It splits what is wired through it to derive a constant common which it identifies as K.

I want to confirm the wiring after adding the c wire thermostat

1. from the control box, the terminals R,G,W,B will be wired to the c wire adapter's EQUIPMENT Rc,G,W-O/B,Y ?

2. from the c wire adapter's THERMOSTAT section to the thermostat base: Rc goes to RC (jumped to RH), W-O/B to W. Then how to wire the other two terminals K and C?

 

[Turtle Blues]

That should be answered on about page 14 of the installation instructions for the thp. Sorry limited to marginal phone service - not trying to dodge the question but I cant quite make out what the page shows.
Instructions appear straight forward for landing your equipment connections so thought would be to just add wires as necessary from the module to your new stat base per the Honeywell diagram.

 

[paulga]

That should be answered on about page 14 of the installation instructions for the thp. Sorry limited to marginal phone service - not trying to dodge the question but I cant quite make out what the page shows.
Instructions appear straight forward for landing your equipment connections so thought would be to just add wires as necessary from the module to your new stat base per the Honeywell diagram.

Thanks.
I found a two page manual on the resideo website.

"G and Y wires are converted to C and K"

 

[Turtle Blues]

I would caution to make sure you are correct with the specific product you end up using. The diagram above does not look the same as the Honeywell products you referenced. The devil is always in the details.