Attwood AC install

Topic: Attwood AC install (Read 2355 times) previous topic - next topic

Re: Attwood AC install

Reply #50 – September 16, 2019, 09:15:30 pm

I will go down to mine and shut off the ac for a little while and see if the aquahot comes on in the heat.. should be hot tomorrow so I will test it.. I will let you know what it does.

Re: Attwood AC install

Reply #51 – September 16, 2019, 09:23:30 pm

Thanks 😊

Re: Attwood AC install

Reply #52 – September 17, 2019, 01:14:40 pm

OK for the continuing saga of my ac install, if anyone cares....
took the cover off the ac topsides, its a ground signal coming from the ac. changed the jumper twice, no change. no signal coming down the wire. There is continuity on the blue wires at the circuit board.
Fans still turn on when 12 volts applied to the white wire going to the aqua hot.
Called Foretravel for tech support, awaiting their call back.
Called Aqua hot, spoke to a service tech. Not much help there. They told me to talk to Dometic.... that's a dead end unless I want to drive somewhere and pay them probably more than I paid for the AC to tell me they don't know much.
So at least the AC's are working well.
Think I will order 2 atwood furnace tstats and wire it up that way. Maybe one day I will pass a dometic repair place and get some answers.... unless Foretravel support is of some help.
I think its a missmatch between the old duo therm ac and this one in the wiring. The amount of wires between the two are much different and how they handle the furnace as well. You can see from the old units the wires are more and different.

Re: Attwood AC install

Reply #53 – September 17, 2019, 07:12:41 pm

Forget about the old harness and the old connections..

I went out to mine.. 90 degrees in it this afternoon... Aquahot will not turn on as the thermostat only goes to 85degrees so nothing happened..

Earlier when it was 68 degrees the aquahot turned on with the settings at 85 (at the thermostat).

WOrks as advertised.

Again on the connections for the Atwood... power connections 3 each (with ground). 12v for the thermostat and the blue wires (1 to the aquahot 1 to ground).

The 12v will need to be ran to the rear from the front (as it is easier than a new wire on the rear)..

thinking you need to order a sniffer (what I call it.. traces the wires and makes noise as you run it close to the wire so you know you have the right wire.. or a toner I suppose).. trace the 2 wires to the aquahot and make sure you have the correct wires when connecting to the blue wires..

Bob... I care buddy. I want to figure this out with you.

Re: Attwood AC install

Reply #54 – September 18, 2019, 12:19:31 am

Thanks David... was getting pretty down about the whole thing.
So perhaps it is just the fact that the temp is to high to make the furnace kick on. I ordered 2 atwood tstats from amazon and was going to just put them in. Now after reading your latest thread not so sure. It will be 2 months at least before it gets cool enough her in Corpus for the tstats to kick on. Maybe I will just wire it up and wait.
I am sure of one thing though, my wiring is correct.
I did trace all the wires with my multimeter. And I know for certain that the wire hook up is correct, and that the wires to the ac and aqua hot are good.
You would think that dometic would say something about that in the booklet that comes with it. Or that there ar jumpers on the board that control the ac and furnace. And what they do.
Ah well, December will be here soon.
Bob

Re: Attwood AC install

Reply #55 – September 18, 2019, 08:16:20 am

If you are able.. turn ac (front and back) to 60-65 early in the am... go out in a couple hours.. coach will be cool enough to test... if on 30amp just do the front... will get under 85 pretty quick... then test. Front is easier as the fans on the dash are easier to hear when they kick on

Re: Attwood AC install

Reply #56 – September 20, 2019, 09:43:40 pm

Quote from: DavidS – September 18, 2019, 08:16:20 am

If you are able.. turn ac (front and back) to 60-65 early in the am... go out in a couple hours.. coach will be cool enough to test... if on 30amp just do the front... will get under 85 pretty quick... then test. Front is easier as the fans on the dash are easier to hear when they kick on

Think I will wait till it cools off here and then try it. I purchased 2 atwood furnace thermostats just in case. The sensors on these units are in the ac on the roof as well as the Tstats in the coach. Don't think that will work David.
In the meantime, on to other projects....

Re: Attwood AC install

Reply #57 – September 20, 2019, 11:42:48 pm

Are your AC ducted? If so Tstat on the wall .. runs AC and aquahot (on the old tstat) .. thermostat controlled everything .. rear has the sensor in the bedroom..

When removing the old system you disconnect everything..

Everything on the new system runs off the thermostat now. 1 for living room 1 for the bedroom and no sensors now besides thermostats ..

If non ducted each Tstat is in the unit..

Pretty sure yours is ducted also. So the same setup as mine was

Re: Attwood AC install

Reply #58 – September 20, 2019, 11:52:43 pm

Yes ducted. Its to hot to have the aqua hot come one with the tstat it seems. All other sensors disconnected.

Re: Attwood AC install

Reply #59 – September 21, 2019, 12:57:34 am

That's what I figured..

Can't you turn the ac in early in the am and cool the front down under 80 degrees? Turn the aquahot on at 85 and see what it does? The suspense would kill me lol

Re: Attwood AC install

Reply #60 – September 21, 2019, 05:41:39 pm

David, looking at the atwood electrical schematic, there are sensors in the AC unit on the roof and I can't cool that area down. In fact, running the AC probably just heats it up.
It should start cooling off soon here and I might be able to see then. At midnight is still in the mid 80's and feels hotter due to the humidity.
I will try it next week though and see. I too want to make it work. I disconnected the front ac from the aqua hot, but its just a simple one wire fix. The rear I left on.
If I need to bypass it, I will do it below, at the solenoid near the aqua hot. Run new wires up to wear I want the TStats to be. I figure one in the bedroom below the atwood ac tstat and the other in the kitchen. next to the jack knife sofa. Easy wire runs.

Re: Attwood AC install

Reply #61 – September 21, 2019, 07:57:41 pm

Maybe I am missing something.. what good is a sensor if you have a thermostat? What good is the thermostat if you have a sensor?

Not understanding I guess.. I am sorry.. you can't turn the air on and cool the coach right now? At all? Front or rear?

Once cooled front or rear .. get it below say 80 then turn the aquahot on the thermostat and see if if the fans kick on

Re: Attwood AC install

Reply #62 – September 21, 2019, 11:31:29 pm

David there are sensors in the AC that monitor air flow, temp etc. Plus the sensor on the status. I tried putting a bottle of ice cold water on the tstat to see if that would do it, and it didn't work. So cooling the coach down probably won't either.

Re: Attwood AC install

Reply #63 – September 22, 2019, 12:30:32 am

On weds I went down and turned the ac on in my coach around 730 am.. put it at 70.. went back down in a couple hours and it was nice and cool in the coach.. turned the ac off at the thermostat and flipped it to furnace /heat.. turned the thermostat to 85 ( max heat setting) the aquahot kicked on.. it was 90 outside at the time..

Simple test to try. Takes a couple hours if the coach isn't cool already.. if cool already(under 78 ) flip the furnace/heat on and see if aquahot kicks on.

Again this is a simple test to see what is working or not.

Everything is controlled from the thermostat but if you can not get cooling.. your stuck.

Re: Attwood AC install

Reply #64 – September 22, 2019, 05:52:47 am

OK. I will try it now and see. Its 0451. Temp outside is 80. Will turn it way down and check it in a couple of hours.

Re: Attwood AC install

Reply #65 – September 22, 2019, 10:56:30 am

David, after a few hours I walked into the coach and it was so cold, my nose froze... and nope, the aqua hot fans did not come on.
At first I forgot to turn the theromastat all the way up, remembered and still no go. Then I checked the wiring.. one ground I had left off in the front ac when I put the covers on, fixed that, still no aqua hot fans. Turned on the bathroom aqua hot and yup, it came on no problem.

Re: Attwood AC install

Reply #66 – September 22, 2019, 11:21:14 am

Quote from: Bob and Julie – September 22, 2019, 10:56:30 am

David, after a few hours I walked into the coach and it was so cold, my nose froze... and nope, the aqua hot fans did not come on.
At first I forgot to turn the theromastat all the way up, remembered and still no go. Then I checked the wiring.. one ground I had left off in the front ac when I put the covers on, fixed that, still no aqua hot fans. Turned on the bathroom aqua hot and yup, it came on no problem.

Well on test down .. on to the next step .. maybe an email to the guy online that sells all the parts.. or join his forum

Re: Attwood AC install

Reply #67 – September 22, 2019, 10:58:08 pm

ok I couldnt leave it alone...Let me see if the attachment worked .. ok it did.. Bob check into this..

http://www.aquahot.com/files/service_manual/AHE-100-02S%20Service%20Manual%20Rev.%20B%209-27-2011.pdf if needed

Zones A B C are negative ground. See diagram to Tstat

Re: Attwood AC install

Reply #68 – September 23, 2019, 11:15:00 am

David, I went over that service manual with a fine tooth comb.
But you have to remember that Foretravel wires it first from the AC to the aqua hot.
They wire it from the AC to the solenoid which then goes to the aqua hot. I'm pretty sure there is no signal coming from the AC. I have not found any electrical activity from the blue wires to the Foretravel solenoid. When I checked for continuity, it was there.
The ONLY way I have been able to activate the aqua hot zone fans, is by applying a 12 volt source to the wire that goes to the solenoid. So that tells me that the AC is not doing that. And that tells me that either both units are defective, which I don't think so, OR, it's to hot to set off the furnace. Which is what I am going for. But since there are sensors in a roof top part of the AC, I think they are inhibiting the signal until it gets colder.
If all else fails, I will tie in to the wires below at the aqua hot and just use the simple tstat like in the bath. It will work.

Re: Attwood AC install

Reply #69 – September 23, 2019, 01:45:25 pm

Had me lost with the new pic lol... I think ... is it possible you fried the 2 relays? (not even sure if that is possible)...Doubt 2 unit would have the same problem unless maybe the same connection that was done was incorrect and is causing the same problem?.. Just guessing.. I can only tell you from experience and how it worked on mine.. same AC and Aquahot..other than that I cant see anything else going wrong on both (not impossible just improbable)..

Re: Attwood AC install

Reply #70 – September 24, 2019, 12:51:48 am

Don't think so. Maybe on the front one, but not the back.
Either way I have a plan.

Re: Attwood AC install

Reply #71 – September 26, 2019, 12:12:29 am

So I have been researching relays. The relay Foretravel uses is a simple automotive type B relay. Usually this is used to control a high current circuit. For the Aqua hot though, that is controlled by a ground signal, it controls a ground relay instead. 12 volts come from the ac unit to the wall thermostat, and when the furnace is called for a relay in the ac sends 12 volts to the relay next to the Aqua hot. This is wire A5 at the front ac and A7 at the rear. That goes to the relay down below, and enters at pin 86 the low current side. The other side of that is pin 85 and is ground. When energized the relay opens up pins 30 and 87. This is normally the high current side, but in this case is a ground signal. The Foretravel relay has 4 wires. 2 green ground wires and 2 white wires. The A5A and A7A go to the Aqua hot. So in order to send a signal to the aqua hot to turn on the zone, a 12 volt signal goes from the TStat to the relay, that then sends a ground to the aqua hot zone. Puzzled why they chose to do it this way. Since there is no high current running thru this circuit.

Anyway David, that is why there is both a ground signal and a 12 volt signal in this system. Took me a while to figure out why and how. Learned a bit more about relays in the process.

Now as to why the circuit is not going thru the AC circuit board is a mystery still. But I still think its about the temp outside. Either that Or both units I received are defective. Just don't believe that is the case though.

Re: Attwood AC install

Reply #72 – October 08, 2019, 08:47:21 am

So cold front came in and outside temperature is 74. Turned on heat mode and heat pump works fine. Turned to furnace and nothing. Tried switching the blue wires around and... You guessed it, nothing.
So I am going to give up on the Atwoods controlling the aqua hot.
Will just put in a simple furnace TStat.

My recommendation is pass on these if you have a aqua hot. Others have gotten them to work but I cannot. No signal is going through.
And each unit has different cables, so it's not that, or how it's wired everything else works.

Re: Attwood AC install

Reply #73 – October 08, 2019, 09:42:16 am

You can pop the covers off of the relay and close the switch by hand . When energized, 2 post have power. One post goes to ground and the last goes to power a system. Just like your pic. You can test the load path with a jumper wire and see if that passes power.
A simple test light will show if the ground for the coil is valid.
Some systems control the ground with steady power to the+ coil side and some control the power side .

Re: Attwood AC install

Reply #74 – October 08, 2019, 04:54:13 pm

I figured that since the aqua hot worked fine before the atwood install the solenoids were ok. But perhaps I should pop the solenoids out and check that before wiring in the separate TStats. Thanks for the suggestion.

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