Those familiar with the AquaHot system in coaches know there are heat exchangers (aka heat registers) dispersed in various locations throughout a coach in which hot RV specific anti-freeze flows. Small fans on the backside of the heat exchanger blow thru the registers subsequently blowing warm/hot air into the coach, providing heat.
From what I’ve read most Monaco’s have an AquaHot main unit however the heat exchangers are not AquaHot brand but made by another company called “HeaterCraft”? While the fans on Monaco registers work well in terms of air-flow some people complain they are noisy. I am one of those people.
Knowing AquaHot sells it’s own comparable heat exchanger that are actually marketed as being “quiet” I set out to see if I could use the AquaHot brand fans on my Monaco registers, thus making them “more quiet” so they won’t give me an annoying headache the next time I listen to them run non-stop in an Oregon winter with a foot of snow outside 🙂
I ordered 2 fans from AquaHot which are shown below (San Cooler 92). The plan of attack regarding the fan replacement was to simply replace the fans in the forward heat register under the drawer in the center console near the driver cockpit. If I could notice a definitive decrease in noise with similar output I would order more to retrofit a few other registers I find noisy (e.g. bedroom).
After removing the slide-out drawer I had full access to the back of the heat register where the fan cage is screwed into rear of register. It is somewhat tricky getting access to the 4 screws that fasten the cage to the back of the register. I used a flashlight and a mirror to assist in locating and removing which I found easier than re-installing later on.
The location with drawer removed, as well as the fan cage.
OEM Fan cage on bottom, new fan shown on top.
The label side of the fans face the heat register. You can see the protective metal screens on the other side of the fans in the picture above which fasten to each fan via 4 screws and also fasten the fans to the cage itself.
Simply remove the fans from the fan cage. The red(+)/black(-) wires from each fans are spliced together and attached to the larger single red/black wires that run from the control unit outside.
The new fans are a direct match/fit to the OEM fan cage. Hooray.
The new fans installed and wired up in the new cage. Ready to be re-attached to the rear of the heat register.
That’s it for pictures. Getting the fan cage re-attached to the rear of the heat register is fun. The screws are small/tiny and you are doing it basically blind with exception of a mirror and flash light…but after a few minutes I managed to get them all in and snugged down.
I then turned on the forward thermostat to “Furnace” which activated the new fans. Wife and I could tell immediately they were quieter but they are NOT silent …which we weren’t expecting. They are probably 50% quieter if I were to guess. I think we had a bad bearing in one of the OEM fans which is why it was annoying to listen to.
All in all a decent test/upgrade. Not sure I’ll retrofit all my registers at this point but will if/when the others start emitting noises indicating they are going bad.
The one I would really like to replace is our 3-speed fan under the kitchen sink area that blows heat out of 3 separate round plastic ducts under the kitchen cabinet area. However I’ve learned this fan is a large squirrel cage type fan, not computer fans as shown above. However it’s definitely annoying and has problems so that one is on the to-do list next.