Can't keep rear of coach cool while driving. I run all three basement units. I have sealed windows, exhuast vents and entry door.Engine compartment insulation is still in good condition. Is there anything eles to try. Help!!
This is a complex question! According to our records, your coach is a 1986 model. A diagnosis is difficult without more information. However, broadly speaking, you could be experiencing a higher heat load (from exterior temperature and engine heat radiation) than the system is capable of cooling adequately or at least to your satisfaction, or the system may not be operating up to specification due to some malfunction or need for periodic service. The first, easiest step is to clean any filters, typically located at the return air grills. A dirty filter can drastically decrease the performance of the a/c. Once the filters are clean, check the temperature of the air at the return air grill and then at the outlets. You should see a minimum of 15 degrees F. difference, more preferably 20 degrees plus. If you do not see this much differential, the system is not functioning properly and you should see an a/c serviceman. If you have 15-20 degrees differential, it would still be a good idea to have an a/c serviceman give your system a "tune-up." Once you have verified that the system is functioning to specification and it is still not offering enough cooling for the back of the coach, you'll need to make design changes to improve performance. The first thing we'd recommend would be to add two or three inches of insulation to the engine "dog house," the floor between the engine compartment below and the bedroom and cabinets above. Probably the easiest way to add insulation would be to lay precisely cut rigid foam on top of the dog house, although, depending on the location, you might need to carpet over it for appearance sake. If you want to finesse the issue and really kill the snake, you might consider installing a new roof air conditioner over the rear area. Unless you are quite skilled and versatile, this is not a do it yourself project, but a competent RV technician could cut the hole, run power, install the unit, and finish off the roof and ceiling. Replacement parts have become a challenge for these older a/c units. You can check on specific parts availability by calling Newell parts at 1-888-363-9355. Please have available as much information as possible for any parts request, including make and model of the central air units (there are data plates on the units with this information).