HELP, no heat

[Sharon_Jon]

Any help greatly appreciated. It's 43° in Spearfish South Dakota and the heat suddenly stopped working. We have a Dometic Thermostat, Dometic A/C heat pump and a furnace (I think Atwood) in our 2014 27 International.

Initially there was an E1 Error code. Then the furnace turned off. The stove continues to function and the 110 V and 12 V systems seem otherwise intact. We are on shore power and have been at the site for five days.

Read the manual, searched online and reviewed Forums. Found a similar thread [http://www.airforums.com/forums/f37/...a-105148.html]. Reset the thermostat. Held down the program key until program disappeared. Now zone one is blinking with a non-blinking "4" off to the right.

Using the mode switch the unit cycles through off, cool, and fan but not furnace or heat pump. This isn't mentioned nor is it anywhere online I can find. I've also thrown the circuit breaker marked A/C off and then on again several times.

Any help is greatly appreciated. . . Brrrrr.

[Foiled Again]

To reset inside breakers you have to push them down all the way before pulling them back up. Do your wall outlets work on AC power? If unsure reset the breaker on the shore power post.

At 42° your heat pump should work, colder it should switch to propane furnace mode... However a furnace sucks propane so you might be low or out. Try lighting a stove burner. And open the valve on the second tank if it's closed.

You don't say whether you have solar or a big battery bank and oversize inverter . Factory OEM lets you use very limited battery capacity thru the inverter.. to keep ypu from ruining your batteries, but even the bigger boondocking systems have limits.

If you set the thermostat to AUTO and 70 degrees the heat pump should start at 67 or so IF your shore power is good. And of course you could run to Walmart and buy a space heater for a short term fix.

The thermostat WAS designed by Satan. But the E1 normally happens when shore power is cut, a circuit breaker pops and/or the backup furnace can't fire.

Paula

[Sharon_Jon]

Thanks so much for your prompt reply.

I have reset the breakers with the correct procedure you describe. The wall outlets seem to work fine. Our space heater is indeed going.

The stove works fine, good flame from the burners. Both tank valves are already open.

We have standard Interstate batteries and a 50 amp Airstream solar panel and inverter. Our system has worked for more than a year of camping days.

Cannot set the thermostat to auto because it only cycles thru off, fan and air conditioner over and over.

Thanks for your thoughts and ideas, we will try turning off shore power at the pedestal.

[Sharon_Jon]

Turned off the power at the pedestal and found that the batteries are very low. But should be a factor when we are on shore power? We've been concerned about that problem and have an appointment with Lewster in Naples but not until February.

[glcmranger]

This happened to me. Your batteries are "Toast"! You need a minimum amount of 12v battery power for the furnace fan to turn on. The exact same error code and symptoms happened to me. I replaced the batteries --- Furnace started working again. It doesn't matter if you're on shore power or have solar. IF your batteries won't hold a charge, it's a mute point!

[Al and Missy]

Have you checked inside the furnace compartment for a fuse or circuit breaker? Go outside, open the door to the furnace and look around for a fuse, breaker or a loose wire. For some reason the control board in the AC unit doesn't know the furnace is there. There could be several reasons: low voltage, bad connection between the thermostat and control board in the AC unit, corroded furnace DIP switch on the control board, or a problem in the furnace itself.

Do you have a voltmeter? If the batteries are at 12.6 volts, the furnace should work. Unless you have a shorted cell, they should read good voltage while the converter is on. If your voltage is OK, you may have a bad connection between the thermostat and the control board in the AC, or the DIP switches that set the configuration may be corroded. Check the cable (like a modular phone cable) between your thermostat and the AC unit. Unplug each end, clean the wire contacts with an eraser, reconnect and reset. If that doesn't work, work the switch that tells the thermostat that there is a furnace present back and forth to clean the contacts, reset and try again.

If you read low voltage, say 10 volts or lower then the batteries have a shorted cell and are pulling the converter voltage down. Then:
1. Disconnect from shore power
2. Disconnect the negative terminals of both batteries and tape them up in plastic bags to prevent shorting to the frame or skin of the trailer.
3. Reconnect shore power
4. Reset thermostat and try again.

NOTE: This will disable your breakaway braking. Reconnect the negative cables or replace the batteries before moving the trailer.

This will remove the load the batteries are placing on the converter and system voltage should go back up to 12 or 13 volts. IF not, your converter is toast. Lights and other things might still work. I don't know the voltage tolerance of the control board and thermostat.

Al

[Sharon_Jon]

Al, thanks so much you're amazingly detailed step-by-step instruction. It worked! We first went outside and checked for loose wires. There were none. There was an on off switch which we switch off and on a bunch of times. Came inside and there was no change.

We next checked the batteries with a voltmeter. With the converter running readings across both was close to 14. We then came inside and remove the thermostat. Tried to clean by blowing and pushing off and on the phone jack. When we replaced the thermostat it showed only done four, hopefully as shown in the attached photo. We only have one zone. The thermostat still did not see the furnace nor heat pump.

We then reset the thermostat and it recognizes zone one and works. Perhaps one of the contacts in the switch outside or on the telephone-like connector was not clean. . At any rate, things are working now and hopefully will remain so. Your help is greatly appreciated.

[capt_ron777]

eVERYONE IS SO KNOWLEDGABLE. Thanking you in advance for your help. WE just-meaning today- picked up a 2017 26 FC from a friend who is already going larger. He has been on shore power for the summer and is not that familiar with the systems. Anyway, it is in our driveway and NOT yet hooked up to the house power. It's getting cold out, around 50 and since I've been "playing" with it all day I decided to try the heat on batt/propane to see how it does. Batt disconnect off. Set thermostat first to HP-nothing. Than changed it to heat and E7 came up. That in the booklet says no 120v- which I knew. But still nothing went on. Propane tanks open. What am I doing wrong? BTW, is it just me or is the AS manuel a pretty non-informatve booklet for such an expensive piece of equipment. Thanks so much.

[Al and Missy]

From the CCC2 Manual -
Press the MODE button to cycle
through the mode options. A mode is
an operation that can be performed
by the unit and is controlled by
the Dometic CCC thermostat. The
available modes are: OFF, COOL,
HP (HEAT PUMP), HS (Heat Strip),
FAN, FURN (Furnace), and AUTO.
The available modes are determined
by your system options.

You need to put the thermostat in FURN mode. HS (heat) is for electric heat strips in the AC unit which are an alternative to heat pump and require AC power to operate. Do you see a FURN mode?

Al

[Sharon_Jon]

We went we went out and came back to find E1 and the system not working again. Still only cycles through off, fan, and cool wrhen the mode button is pushed. . I've tried the same things as last time but can't now get zone one in operation. After the word zone in the picture the "1" is flashing and the "4" is on constantly. Any other ideas or appreciated.

[glcmranger]

As I mentioned before: REPLACE YOUR BATTERIES! Turn disconnect switch to STORE -- Wait an hour. Take voltmeter reading at the batteries. Any reading below 11.7 means batteries compromised and FURNACE WILL NOT TURN ON!

[Lily&Me]

One of the things it might be good to put on your must-have list, for just such furnace kaput occasions, is one of the small, highly efficient space heaters that many of us carry.

It won't fix the furnace issues, but they provide an amazing amount of heat and even visual comfort if you get one of those that looks like a tiny fireplace.

Our thermostat went out in the second year or so of ownership, and the space heater saved us from freezing solid when we were stranded during an ice storm in Missouri.

Just a thought for future events...

Maggie

[capt_ron777]

To Al, I think your response was to me. I am sorry, I meant to say furnace. That is what I put the mode into and it did nothing but said E7. One other question if you would, I'd like to get a fuel gauge for the two propane tanks. Any recomendations and where does it get placed. Is the present one- which on mine right now is showing all green with an arrow I guess pointing to operable tank- at all reliable? Thanks again

[capt_ron777]

sorry , just went back in to as and played with the thermostat again. Put it in different program- 1- and went to furnace and set temp to 70- inside temp is 39- and nothing goes on. Also this time didn't say E7, just showed set temp for 70 ,but no response. Am I not turning something else on?

[Al and Missy]

Originally Posted by capt_ron777

To Al, I think your response was to me. I am sorry, I meant to say furnace. That is what I put the mode into and it did nothing but said E7. One other question if you would, I'd like to get a fuel gauge for the two propane tanks. Any recomendations and where does it get placed. Is the present one- which on mine right now is showing all green with an arrow I guess pointing to operable tank- at all reliable? Thanks again

The regulator/gauge you have is accurate. If you have it pointed to the roadside tank and it is green, there is propane in that tank. When that tank gets low the indicator will show red, but it will automatically switch to the other tank. At that time, move the lever to the other tank. You can then pull the empty tank and get it refilled. You are supposed to be able to do that without turning the full tank off, but my regulator failed in such a way that propane from the good tank came out of the fitting for the empty tank. If possible it is better to turn the active tank off when you pull a tank. You can turn the lever at any time to check the other tank.

My trailer has gauges built in to the tanks that are monitored along with the water and waste tanks. I have now experience with adding any other means.

Al


Al

[Lily&Me]

Originally Posted by capt_ron777

sorry , just went back in to as and played with the thermostat again. Put it in different program- 1- and went to furnace and set temp to 70- inside temp is 39- and nothing goes on. Also this time didn't say E7, just showed set temp for 70 ,but no response. Am I not turning something else on?

Since you have a new rig, might call the service department at your dealership and see if they have any thoughts on this, in addition to what you are getting here.

Maggie

[Al and Missy]

Originally Posted by capt_ron777

sorry , just went back in to as and played with the thermostat again. Put it in different program- 1- and went to furnace and set temp to 70- inside temp is 39- and nothing goes on. Also this time didn't say E7, just showed set temp for 70 ,but no response. Am I not turning something else on?

The way I understand the system to work is the thermostat sends a signal to the control board in the AC unit to turn on the furnace when the temperature is lower than the set point. The AC control board then sends a signal to the furnace to turn on. At that point the blower should start. The intent for this is to purge the system of any residual propane before lighting and to ensure that the heat from the burner will be dissipated before turning on the gas. A "sail switch" confirms the presence of air flow and, after a delay, the gas is turned on and the ignition sparks to light the gas. The furnace will try several times to light the fire but if no heat is detected it will turn off the blower. In order to reset it, at least with my furnace, you must kill the 12V to the furnace either by the appropriate fuse/breaker, the store/use switch, or the on/off switch inside the furnace itself. Assuming it was working before, it may have tripped somehow. Open the outside furnace door and find the on/off switch. Turn it off, wait a minute, and turn it back on.

Then observe what happens. IF the blower doesn't turn on either there is no 12V at the furnace (check 12 breakers/fuses), the thermostat is not communicating with the control board, the AC control board is not communicating with the furnace, or the furnace control board is bad.

All of the above "in my experience", YMMV.

Al

[Foiled Again]

ZONE 1 is probably the only one that will do anything. Zone 2 is meaningless except for units with 2 A/C units.

[capt_ron777]

Al, thank you so much for your detailed explanations. I am off today and plan on going through the system as you describe. Hopefully will find the culprit. Appreciate everyone's time immensely. Will let you know. Ron.

[capt_ron777]

Well so after going through all the systems as outlined above, I found the problem. At the end I re-read the Thermostat booklet and after re-setting everything and going to only zone 1-you were certainly right Foiled Again, zone 2 only AC- it went to furnace and voila, the blower went on and than the furnace. Nice toasty heat, although the front vent is significantly stronger than the back- guess thats because it's right up against the furnace. Thank you all so much again. Have I said before that this forum rocks!! PS am I right that the AS manuel is lacking in detail.Ron.