rcoon2 Report post Posted July 27, 2018 Hello everyone. My coach is a 1995 beaver marquis. The rear AC stopped working for some reason. Just makes a loud crunching sound when i turn it on. I am guessing it's coming from the compressor. The roof top air conditioners are original to the coach, given its age i am not interested in wasting time troubleshooting the bad unit. I plan on moving the working AC from the front to the back and putting a heat pump up front. Are there any trick to figuring out what to replace the faulty unit with. The current AC units are Duo-therm 13,500 BTU ducted air conditioners. I plan on bumping up to 15K BTU heat pump. Am i confined to putting in duo-therm units or does it not matter? I plan on replacing the thermostat as well. The thermostat needs to operate the aquahot system as well. Any helpful ideas / guidance will be gratefully appreciated. Thanks, Rick Share this post Link to post Share on other sites
manholt Report post Posted July 27, 2018 A 15,000 BTU with Heat Pump is going to draw more Amps! Since your keeping your coach, I would replace the 3 Duo-therm 13,500's & Thermostat...heat strip on the front. They are 23+ years old. Share this post Link to post Share on other sites
hermanmullins Report post Posted July 27, 2018 Rick, I was looking into doing the same as you. I was going to replace my rear unit, a Dometic 13,000 btu with a 15,000 btu/heat pump 9my unit has a heat pump. Dometic said it was no problem but would need a new thermostat but that it would use the same wiring. A call to Dometic will get all the information you need. Do you plan on doing it your self or hiring it done? Also I would just replace the rear and not move the front one. Since the front one is also 23 years old also, it may not be long before it also dies on you. Then you can up grade it to. Good Luck. Herman Share this post Link to post Share on other sites
richard5933 Report post Posted July 27, 2018 Every roof-top I've seen being sold will fit into the same opening, so you are not limited to the Duo-Therm. We had an Atwood Air Command 15K unit with heat pump and liked it very much. Not terribly noisy and both the heat and a/c seemed to work for us. Depending on how your current unit is installed, you may or may not need a new thermostat. If you are switching from 13.5K to 15K, you'll need to do a little homework first. First thing to check is the rating of the circuit that is powering the a/c unit - is it 15 amps or 20 amps? Remembering that you don't want to consistently run a circuit at more than 80% of the rating, get the numbers on the new unit and see what will work within the limits of what circuit you've got. Some of the newer 15K units will actually run on the same current draw as the older 13.5K units since they are more efficient, so you might not have any problems. When we installed the Atwood, we did the work ourselves. To get the unit up to the roof we had to be creative since I didn't feel safe lifting it on my shoulder while climbing the ladder. What we did was did was use one half of a 40-foot extension ladder as a ramp. I built a 'sled' (out of a piece of scrap plywood with two bottom side runners) that could run up the ladder ramp. Then I strapped the Atwood to the sled. We drilled a hole in the end of the sled for a rope, and then just pulled it up the ramp from the roof of the coach. Once it got to the top end of the ramp I tied it off and then lifted the Atwood from the ramp to the roof. It was slow, but I was able to get the Atwood onto the roof without injury or damage. Of course, you'll have to have a long enough ramp to make this work depending on the height of your coach. Share this post Link to post Share on other sites
rsbilledwards Report post Posted July 27, 2018 New territory here for me...Really, the difference between 13.5 and 1,500 is a noticeable difference? Addition of a heat pump/ an explanation would help a lot B Share this post Link to post Share on other sites
richard5933 Report post Posted July 27, 2018 56 minutes ago, rsbilledwards said: New territory here for me...Really, the difference between 13.5 and 1,500 is a noticeable difference? Addition of a heat pump/ an explanation would help a lot B When we installed the new 15K BTU Atwood, the current draw was rated as the same as the 13.5K we were replacing since it was a more efficient unit and able to make more cold from the same current. There might be only a slight increase in cooling capacity, but since the difference in price was minimal we went with the larger capacity. The heat pump is an alternative to the heat strip. Where the heat strip works basically the same as a hair dryer by using electric current to heat the element, the heat pump in essence runs the a/c unit in reverse. Instead of absorbing heat from inside the coach and dumping it outside, the heat pump absorbs heat outside and dumps it into the coach. The only downside with the heat pump is that they don't work in extremely cold weather. We tested ours down to the upper 30s outside temp and it made heat nicely. Don't know what the actual limits are. The main purpose of the heat pump inside the a/c unit is not to replace a furnace, but rather to take the chill out of coach on a cool morning. Much easier to just flip a switch and run the heat pump for a few minutes than to get the LP system fired up in our coach, especially just for a few minutes of use. The heat strips would do the same thing, but generally are not as efficient and they tend to have a strange smell unless they are used often. Share this post Link to post Share on other sites
rcoon2 Report post Posted July 27, 2018 Thanks for the info everyone. My two air conditioners are on separate 20 amp breakers and pretty much all the 15K BTU units seem to be about equivalent to the current draw of my 23 year old units, so no problem there. Yes i am going to install myself. My wife had a good idea for getting them up to the roof. We are going to rent a man lift to trim some of our trees so we will use that as long as the timing comes out right. Thanks to all and I will update as soon as i get them installed, have a good day, Rick Share this post Link to post Share on other sites
kaypsmith Report post Posted July 27, 2018 Rick, that is great news and the manlift should work nicely. Bill, the heat pump is as Richard describes it and the way it works, most of them also come with heatstrips to be installed, because the heatpump becomes very inefficient below about 40 degrees. The big advantage in using over a regular AC is the fact you wont need to use propane or whatever fuel you currently use nearly as often, also by utilizing the compressor nearly all year, the units normally have a longer longevity due to the unit is exercised almost year round. I'm sure that you are aware that auto makers added AC to the defrost capability in their cars for the same reason, exercise the unit during the winter months. 1500 btu is a little over one tenth of a ton in AC and is very noticeable in most cases. Share this post Link to post Share on other sites
manholt Report post Posted July 27, 2018 The down side is the amount of current the heat pump uses on start up and on/off cycling....Aqua hot will run on both elect. & diesel for furnace with less spike on current. Share this post Link to post Share on other sites
five Report post Posted July 29, 2018 On 7/27/2018 at 5:16 PM, manholt said: The down side is the amount of current the heat pump uses on start up and on/off cycling....Aqua hot will run on both elect. & diesel for furnace with less spike on current. We have a heat pump on our rear unit....very seldom use it. Much quieter to use the Aqua Hot (on electric) and/or floor heat. Share this post Link to post Share on other sites
manholt Report post Posted July 29, 2018 FIVE. We have the same! I only wish I had the Oasis, rather than Aqua Hot. Floor heat is set at 80 and works good...on now! 66 degrees and rain at 7,150' elevation, will be 54 in AM ! Share this post Link to post Share on other sites
rcoon2 Report post Posted July 29, 2018 All good ideas gentleman, however my aqua-hot system is as previously mentioned 23+ years old and has worked on diesel (since i have owned it) a total of 3 hours after a tune up! The system works well enough on electric for domestic hot water but is inadequate to keep the coach warm even in a mild florida winter. Also the 23 year old hydronic heat exchanger fans are anything but quiet.I suppose i could shell out several hundred thousand and upgrade to a new coach or $10+ grand for a new aqua-hot system. Nope i think i'll be putting a $1500 heat pump to the test and see how that works. Talked with Dometic on Friday, they were able to give me a "direct replacement" for my aged air conditioners as well as upgrades to the thermostats. Any idea where is the best place to order them from? Thanks for your thoughts everyone. Share this post Link to post Share on other sites
richard5933 Report post Posted July 29, 2018 Where are you located? I got my unit through a small shop in Elkhart, IN. Share this post Link to post Share on other sites
manholt Report post Posted July 29, 2018 Dometic comes to mind. PPL in Houston, Texas. Amazon. Take your pick....I would go with Dometic Direct or someone they recommend! Share this post Link to post Share on other sites
rcoon2 Report post Posted July 31, 2018 I am Located in northern Florida, just sold my house in Northern WIsconsin! Dometic only recommends service centers which is probably the easier option. But I like to do my own fixin PPL seems to have the best price but oddly enough they do not sell the appropriate thermostat. Guess I can go PPL for the AC unit then go Amazon for the thermostat. Thanks to all, Rick Share this post Link to post Share on other sites
manholt Report post Posted July 31, 2018 Hope you update us! Share this post Link to post Share on other sites
rsbilledwards Report post Posted July 31, 2018 Rcoon2 You are doing exactly what I would do. Share this post Link to post Share on other sites
kaypsmith Report post Posted July 31, 2018 Here is a place that I have done business with for many years, located in New Port Richie Fl. https://www.dometic.com/en-us/us/find-a-dealer/united-states/florida/new-port-richey/family-rv-center-ii-4158-marine-parkway Might be worth giving them a call. Share this post Link to post Share on other sites
ivykrewe Report post Posted July 31, 2018 Try RV Parts Country. 15K Dometic Penguin II heat pump $958. plus shipping. Several thermostats to choose from. I am going to change 2 of mine. Share this post Link to post Share on other sites
richard5933 Report post Posted July 31, 2018 If you have a place near enough to drive to, you might consider going to pick up the unit if at all possible. The place that I purchased from warned me that the a/c units are not typically packaged for individual shipping. They usually arrive to a dealer on a pallet - when they break the pallet to ship the units individually they are just labeled and shipped out as they are with no additional padding/packing. I drove from Milwaukee to Elkhart IN to pick up our Atwood to make sure that it arrived without damage. If you read the reviews on Amazon (or other online retailers) you'll read about people that had units damaged in shipping. Share this post Link to post Share on other sites
manholt Report post Posted August 1, 2018 Good Point. Share this post Link to post Share on other sites
kaypsmith Report post Posted August 1, 2018 I have bought 4 from Family RV to date, all shipped, all crated, and arrived with no damage, that was part of their $99.00 shipping cost. Share this post Link to post Share on other sites
richard5933 Report post Posted August 1, 2018 37 minutes ago, kaypsmith said: I have bought from Family RV to date, all shipped, all crated, and arrived with no damage, that was part of their $99.00 shipping cost. Glad to hear that at least one dealer knows how to properly package things for shipping. Share this post Link to post Share on other sites
rcoon2 Report post Posted August 1, 2018 Thanks for the input everyone. Apparently there are many models of Penguin II AC / Heat Pumps. I went down many rabbit holes chasing the illusive sub $1000 penguin only to find it was the wrong part number I searched many online sources with seemingly good prices. But once you dig into the meat of the offer, add in shipping and wait time they turn out to be not such a good deal. The cheapest i found was PPL $1200 ish, But when you add in shipping it wasn't that great of a deal and unfortunately they didn't stock the unit so it was a minimum of 2 weeks out. Turns out Amazon had one of the higher prices $1442 but no shipping cost and delivery next week! Plus if there is damage amazon usually makes it insanely easy to return items. Not trying to promote amazon they don't always have the best deals just worked out this time...i hope Now back to my bathroom floor tiling project! Have a good day all! Share this post Link to post Share on other sites
manholt Report post Posted August 1, 2018 Thanks for the update! Hope it works out for you, flooring included. Share this post Link to post Share on other sites
