Community Forums

chboone · 07-21-2015, 10:55 PM

Quote:

Originally Posted by 70gsconvt

I called one place and told them the model number I wanted and I needed the upper unit along with the seal. They quoted me for the units and then started telling me how I needed control adapter units that didn't come with the upper unit. What the heck would that be? I would think a new upper unit would come ready to go, especially if it's going to be connected to a new thermostat. I may have to call Dometic to make sure I'm getting the right stuff that'll hook up to the wiring that I currently have in the wall and make sure I'm buying just what I need. I can get both upper units for $900 brand new with the seals, but that's it. No inside anything and no thermostat. I wish I wasn't on the road right now. Internet is sketchy at best so it's tough to connect with everyone I want to.

If you look in the return air above the filter you will see the control box in each AC unit. To change to the 5 or 10 button Comfort Control the control boxes need to be changed to match the new thermostat. There are dip switches in the control boxes that need to be set for #1 and #2 AC, furnace and if you have heat strip or heat pumps. There is also a number of wires that need to be connected in each control box.

okrvrepair · 07-22-2015, 10:06 PM

You do understand there is no switch for #1 ac right?

chboone · 07-22-2015, 11:25 PM

Quote:

Originally Posted by okrvrepair

You do understand there is no switch for #1 ac right?

If your asking me, I would have read the instructions again, it's been a couple of years since I replace the 4 button with the 5 button control. I do remember having to change some of the dip switches in zone 1 for the furnace, heat strip and I thought for which zone it is.

70gsconvt · 07-24-2015, 10:37 AM

OK so I'm going to have to buy two control boxes, one for each unit, and wire them into the new thermostat?

trode · 07-24-2015, 12:23 PM

As I am reading this and thinking about my "groaning" rear unit and it's possible replacement, I realize my set up is entirely different, I think. I have a 2004 National Seabreeze with 2 units, they are on a common duct system but are separately controlled by individual thermostats, one in bedroom one in living area. I love this system, since at night when sleeping I can run only the front unit and reduces noise significantly in bedroom, conversely when we are up front in the evening watching TV we run the rear unit and, again, don't have to deal with the noise. Day time with sun on unit in hot weather is really the only time I need to run both units at same time. That is a rare, usually run just one.

SO....I assume replacing only one unit is no issue with this set up as the only thing they have in common is duct work. True?

BFlinn181 · 07-24-2015, 12:27 PM

Quote:

Originally Posted by trode

As I am reading this and thinking about my "groaning" rear unit and it's possible replacement, I realize my set up is entirely different, I think. I have a 2004 National Seabreeze with 2 units, they are on a common duct system but are separately controlled by individual thermostats, one in bedroom one in living area. I love this system, since at night when sleeping I can run only the front unit and reduces noise significantly in bedroom, conversely when we are up front in the evening watching TV we run the rear unit and, again, don't have to deal with the noise. Day time with sun on unit in hot weather is really the only time I need to run both units at same time. That is a rare, usually run just one.

SO....I assume replacing only one unit is no issue with this set up as the only thing they have in common is duct work. True?

My RV has a similar system. You just have to make sure the A/C you're replacing is compatible with the thermostat that controls it.

70gsconvt · 07-24-2015, 10:47 PM

Go up on the roof and verify the brand and then on the inside when you take the cover off you can get the model/serial numbers. Then call the manufacturer like I did with Dometic. They are very helpful helping you get the correct replacement that'll work with your coach's current wiring. Good luck.

chboone · 07-24-2015, 11:24 PM

Quote:

Originally Posted by trode

As I am reading this and thinking about my "groaning" rear unit and it's possible replacement, I realize my set up is entirely different, I think. I have a 2004 National Seabreeze with 2 units, they are on a common duct system but are separately controlled by individual thermostats, one in bedroom one in living area. I love this system, since at night when sleeping I can run only the front unit and reduces noise significantly in bedroom, conversely when we are up front in the evening watching TV we run the rear unit and, again, don't have to deal with the noise. Day time with sun on unit in hot weather is really the only time I need to run both units at same time. That is a rare, usually run just one.

SO....I assume replacing only one unit is no issue with this set up as the only thing they have in common is duct work. True?

You can do the samething with the single Dometic 4 or 5 button Comfort Control. Just select which zone 1 or 2 (front or rear) you want to run, the AC's supply are a common duct system. Temperature sensors are in front for zone 1 and in bedroom for zone 2. Don't know what interface between the 12V thermostats and the 120V AC's they used for your system and if replacing the AC's would require replacing the interface. With the Dometic Comfort Control you don't need to replace the control boxes unless your upgrading the thermostat as long as they are compatible with the new AC's.

70gsconvt · 07-25-2015, 08:41 PM

Like I've said, I plan on just replacing both units and the thermostat, so I'm hoping that I don't need to buy two new control units to go along with them. I'm thinking they're already setup for the newer thermostat. I'm going to call Dometic next week and make sure on everything before I buy the units/theromstat.

Hit_the_Rhod · 07-25-2015, 09:05 PM

x 4 on the heat pump!!!

figallegro · 07-25-2015, 09:30 PM

I say no to a heat pump due to being inoperable in lower temperatures. My former coach had two 15K A/C units with heat pumps. When we were in temps of 40 degrees or less, there was little or no heat. Our current older MH has one a/c unit with a heat strip which has worked well in cold temps. While at a rally this week, I talked with a Dometic rep and heat strip models are available and use the same or a little less power and are a little less expensive than a heat pump. Thinking of upgrading to a larger A/c unit to better handle our cooling needs and will go with a heat strip after experience with both. Talked with a few others and they agree on the heat strip if they replace their heat pumps as they also experienced cold temps without heat and had to run their furnace.

chboone · 07-25-2015, 11:30 PM

Quote:

Originally Posted by 70gsconvt

Like I've said, I plan on just replacing both units and the thermostat, so I'm hoping that I don't need to buy two new control units to go along with them. I'm thinking they're already setup for the newer thermostat. I'm going to call Dometic next week and make sure on everything before I buy the units/theromstat.

If your upgrading to the 5 button or any other from the 4 button you will need new control units

Hit_the_Rhod · 07-26-2015, 08:30 AM

Only the original poster can answer what system will work best for him/her, however some things to consider when deciding whether to go to a heat pump or not.

- Cost, they are more expensive to purchase
- Age of coach, or how long you expect to keep it, doesn't make a lot of sense to go high end on an older coach you plan to sell in two years.
- Installation, this is a wash, as the labor involved is the same either way
- Ambient air temperature- yes, heat pumps are not efficient at lower temperatures, that's where your current usage (and possible change to usage at a later date come into play, for instance retiring soon, and going full time may change how you use your coach) will come into play.
- How do you use you coach, for instance, if you use it for longer stays in cooler (not COLD) climates where you will be using the heater, many parks charge you actual electricity used, not just a flat rate. Heat pump will return a savings on that as long as the temp falls within range of efficiency for heat pumps. Heat strips can be EXPENSIVE to use for longer periods!

Just my $1.89 worth (2 cents adjusted for inflation!)

TQ60 · 07-26-2015, 09:27 AM

Heat pumps are free heat when not paying for electric and if properly setup with lp furnace they both interplay to get the job done.

Contact dometic with your existing model and serial number and detail of what you wish to do and they can supply a complete list of what you need to get it done down to the screws.