Carver Owners Forum

The fwd HVAC is in the auto mode but never turns off. The salon/aft controller is also in the auto mode but it will turn off when temp is satisfied.

Edit: when I turn the fwd HVAC controller ON, the fan starts immediately. It stays ON regardless of fan or mode selection. It’s as if the fan is wired directly to the electrical power. I know I’ve checked the fan speed, but cant 100% say it changes speed? I’ll have to check that to be sure speed setting can be changed next trip to marina. This might warrant a call to customer service, if there is one? Could be something is incorrectly installed. It wouldn’t surprise me.

Just to clarify, there's a "fan" AUTO and a "mode" AUTO... are they BOTH in AUTO? The one pic posted shows that unit in "Dehumidify", which, according to the instructions: "the unit will operate in cooling mode and the fan will run on low speed"

If both are in AUTO, then you might try swapping the two controllers and see if the problem follows the controller. (they were identical units(other than size), right? ) Possibly you just have a defective controller.

Yup...take it off dehumidify....that is constant fan in a certain temp range near as I can tell....

km1125 wrote:QR_BBPOST Just to clarify, there's a "fan" AUTO and a "mode" AUTO... are they BOTH in AUTO? The one pic posted shows that unit in "Dehumidify", which, according to the instructions: "the unit will operate in cooling mode and the fan will run on low speed"

If both are in AUTO, then you might try swapping the two controllers and see if the problem follows the controller. (they were identical units(other than size), right? ) Possibly you just have a defective controller.

Only the fan is selected to “Auto”. The “Mode” is in the sunburst (Heat) selection.

I will swap them next time I’m at the marina to see what happens.

I couldn’t get the picture posted yesterday of the controller that is running the fan constantly. I kept getting a “HTTP Error” response.

Will see if it works from home WiFi:
The above picture is the controller that has constant fan on. I have tried it with Fan NOT in Auto mode with same results.

Side note....As you noted the ac pulls from the fwd bilge since it's a open shot. So stupid or lazy engineering in my opinion. On my 405 I removed the unit under the bed. Built a box and a return duct to the existing grille under the bed.this isolates the unit from pulling any bilge air it can now only pull cabin air. Then Reinstalled the ac unit in this box. Immediately you will notice a big difference in performance and smell. This is not easy because of space etc. But has made a big difference on my 405..

g36 wrote:QR_BBPOST Side note....As you noted the ac pulls from the fwd bilge since it's a open shot. So stupid or lazy engineering in my opinion. On my 405 I removed the unit under the bed. Built a box and a return duct to the existing grille under the bed.this isolates the unit from pulling any bilge air it can now only pull cabin air. Then Reinstalled the ac unit in this box. Immediately you will notice a big difference in performance and smell. This is not easy because of space etc. But has made a big difference on my 405..

Yes, it makes a huge difference! I completed that task last October and even installed a 10x12 grill with 1” filter. It’s an extremely efficient improvement. As you say, the performance is greatly improved and there’s no longer that bilge smell in the cabin. But the fan ran 100% of the time before I Did that.

I didn’t remove my unit. I just built an air handler box and cut the hole for the filter/return in the fiberglass. Then sealed off the OEM return hole. It had a piece of foam for a filter and was ineffective to say the least since all the return air was coming from the bilge, not the cabin.

Greetings folks!! Well I made it back from the land of tall mountains and cold weather. Return to the sunny south!!
And back on the boat again; continuing to HVAC fan issue.

I removed the wall controllers and the model numbers are different so I did not attempt the swap to see if that fixed my problem. One controller is Z5A35B and the other is Z5A35. Difference is one is the “Classic” and the other is the “Platinum”. I’m not sure about swapping them?

I did check that the fan speed does change when moving the controller selection.

Fan still runs continuously regardless of controller selection.

Looking for other recommendations!!

Followup from a previous question; the controller is in the heat mode, not the dehumidify mode.

Well the troubleshooting continues. Attached is a page from the FCF 12,000 Quick Reference Guide (QRG). The HVAC unit is the Webasto "Classic" model. The QRG indicates the fan will continue to run in the HEAT MODE and the COOL MODE after the compressor stops. These manuals are translated/written in broken English and sometimes key words are omitted or nor translated correctly. None-the-less, if the QRG is correct, this unit's air handler will continuously run as long as the Power is on regardless of the MODE.

Does anyone else read this differently or have hands-on experience? Any assistance is appreciated.

I think you're reading it correctly.

Actually if the fan is running on low all the time the unit is not on heat or cool it is better for conditioning the cabin by keeping air moving and mixing......efficiency would be better like that, keeps stratification to a minimum.