420/44 DB Owners Club

[bbwhitejr]

Then when the slots get to the AC area is there an opening? this is where mine is sealed shut.

The slots are open into the area where the AC unit sets. When i relocated my temp sensor, I pulled the wire out through the open slot. The two openings are below the mattress platform. The entire area under that platform is open on my boat. In that opening sits the AC unit.

Bennett

 

[Tomco]

The slots are open into the area where the AC unit sets. When i relocated my temp sensor, I pulled the wire out through the open slot. The two openings are below the mattress platform. The entire area under that platform is open on my boat. In that opening sits the AC unit.

Bennett

That makes total sense to me ... my boat has probably been sealed up since new (sounds like irie's as well). Why did you relocate the temp sensor to under the bed space?

/Tom

 

[Tomco]

Do you get water flow and does the compressor kick in at all? Do you at least get cooling? I had a similar no heat situation this spring and turned out to be a fried triac switch in the control box.

How did you diagnose this? was this a replaceable part?

 

[Irie308]

I called a Dometic and told them my symtoms (Compressor not cycling and no water flow) and he said it sound as if it was the triac. I figured it was the cheapest option and something i could swap out myself before i called in the pros. But it sounds as if your compressor is working? As stated earlier the water temps will affect the units ability to make heat.

 

[Irie308]

Was curious what people have changed the light under the bridge to? The two chrome ringed lights under the bridge overhang. Was looking for LED white and possibly blue.

I couldn't find a bulb that did red and blue without swapping out the entire fixture so just went with the white led bulb replacement

 

[Irie308]

Wondering what cruise speed/rpm are for those with the 450C with full fuel,water and gear.

 

[Carpediem44DB]

I have a spare set of props from an unfortunate encounter with an unmarked outcropping of rocks... long story from the past. I am about to have a prop shop repair them and modify them from 24 to 26 inch diameter. I currently have 24X27 four blade props but have learned that the standard props were 26 inch. My WOT RPM is 2680 so I know I have some room for more prop. I am wondering what those of you with 44DBs with QSC 8.3 500 HDs have for size and pitch in your props and are you satisfied with the performance?
Thanks
Carpe Diem

 

[Tomco]

Wondering what cruise speed/rpm are for those with the 450C with full fuel,water and gear.

Haven't seen a comprehensive table of actuals for the 450's but one was done for the 480CE - check post #1070 & 1075 (page 54). There are a few posts along the way that peg the cruise rpm at around 2200 (~85% of max). Would need to know the fuel flow (and boost) in order to better tweak the number.

I still need to validate I have the correct prop before comparing numbers (need to resolve a bouncing tach issue first). The 6CTA thread is a good one to follow and the most recent posts go to getting this correct for our mechanical engines. Only then can you compare to someone else's (which arguably doesn't matter if yours is prop'd correctly).

/T.

 

[Irie308]

Yes, read over some of those numbers and have read up on the 450C thread as well but i'm not seeing any reference to what most experience fully loaded with gear. Granted this will differ based on how you are outfitted. For example we have a hydra platform and a 450lb dingy setup. Fuel and water tanks are generally full. The admiral also loves to bring everything plus the kitchen sink. However I just wanted a rough idea as to what to expect fully loaded at 2200 rpm as it seem to be the common/recommended cruise rpm.

 

[bbwhitejr]

That makes total sense to me ... my boat has probably been sealed up since new (sounds like irie's as well). Why did you relocate the temp sensor to under the bed space?

/Tom

I relocated the temp sensors on both units to get a "real time temperature." I also have the fans on intermittent so they come on with the compressors. This way, the temp and feel is as close to the same as our house as I can get it. The sensors are located in front of the fins on the unit and are measuring the air temp as it is pulled into the unit. This is quite different than the nominal temp in the cabin. I set the units on 74* in summer and 68* in the winter-same as we do at home.

Bennett

 

[douglee25]

I relocated the temp sensors on both units to get a "real time temperature." I also have the fans on intermittent so they come on with the compressors. This way, the temp and feel is as close to the same as our house as I can get it. The sensors are located in front of the fins on the unit and are measuring the air temp as it is pulled into the unit. This is quite different than the nominal temp in the cabin. I set the units on 74* in summer and 68* in the winter-same as we do at home.

Bennett

I've had mixed results doing this in the past. Try it and see, but I have also frozen up the condenser relocating the sensor.

 

[becnme]

I have a spare set of props from an unfortunate encounter with an unmarked outcropping of rocks... long story from the past. I am about to have a prop shop repair them and modify them from 24 to 26 inch diameter. I currently have 24X27 four blade props but have learned that the standard props were 26 inch. My WOT RPM is 2680 so I know I have some room for more prop. I am wondering what those of you with 44DBs with QSC 8.3 500 HDs have for size and pitch in your props and are you satisfied with the performance?
Thanks
Carpe Diem

You are probably propped correctly. 2680 is the RPM you want to achieve with the boat full of fuel and loaded the way you will use it. I am in the process of purchasing an 07 44 with QSC 500's that has 24x27 props and does not hit full RPM. As soon as I get it home I will have the pitch reduced. The proper way to decide on pitch is to check the fuel burn with the Cummins prop curve for our engines. The boat I am interested in was off by 2-3 GPH in the RPM range I want to run these engines. This will hurt these engines over the long run. As far as performance I would rather loose a little speed than run these engines out of the factory recommended prop curve.

 

[bbwhitejr]

I've had mixed results doing this in the past. Try it and see, but I have also frozen up the condenser relocating the sensor.

They work perfect in my case.

Bennett

 

[bbwhitejr]

I called a Dometic and told them my symtoms (Compressor not cycling and no water flow) and he said it sound as if it was the triac. I figured it was the cheapest option and something i could swap out myself before i called in the pros. But it sounds as if your compressor is working? As stated earlier the water temps will affect the units ability to make heat.

I am having issues with a compressor starting up at times on my newer unit. I emailed them today. When you called, did you talk to anyone in particular/

Bennett

 

[bbwhitejr]

I am having issues with a compressor starting up at times on my newer unit. I emailed them today. When you called, did you talk to anyone in particular/

Bennett

Sweet Jesus! A $40 repair! Dometic emailed me back and told me to do a factory reset-already did that 2 months ago. Tried this again-no go. I tried a few more things they suggested-no go.

A couple weeks ago, dtfeld, suggested it might be the run/start capacitor. I ordered one from Yachtaide Marine and got it this week. The last thing Dometic suggested was to change it.

We have not missed a beat since I changed it 4 hours ago. It is forecasted to be 96*+ for the next few days so this was a big win!!!!

Bennett

 

[Scott Walker]

Was curious what people have changed the light under the bridge to? The two chrome ringed lights under the bridge overhang. Was looking for LED white and possibly blue.

I must have ordered/tried 20 different LED bulbs with no success, UNTIL I found superbrightleds.com. I just received the 1142-B12-G: 1142 Blue Globe, and the 1142-WW12-G-2PK: 1142 Warm White Globe - 2 Pack. They both actually seem to work!!

 

[bbwhitejr]

Sweet Jesus! A $40 repair! Dometic emailed me back and told me to do a factory reset-already did that 2 months ago. Tried this again-no go. I tried a few more things they suggested-no go.

A couple weeks ago, dtfeld, suggested it might be the run/start capacitor. I ordered one from Yachtaide Marine and got it this week. The last thing Dometic suggested was to change it.

We have not missed a beat since I changed it 4 hours ago. It is forecasted to be 96*+ for the next few days so this was a big win!!!!

Bennett

Short lived excitement...Changed the capacitor on Friday afternoon and it worked perfect for about 16 hours. Back to doing the same thing. Compressor may or may not start and stay running. Gets progressively worse until resetting it won’t get it to run.

Sunday morning, reinstalled the original capacitor only for the unit to start up and run as it should when it would not on the new capacitor.....back to the drawing board. Will call Dometic on Tuesday morning. In their email, they mentioned a start relay, but don’t see it and have not a clue.....

More to follow.

Bennett

 

[searay495]

Thanks for the advice on the bulbs. Will order soon.

 

[Irie308]

Noticed that we have 2 vent filters on the head system. I don’t think this is original. I believe the original was such a pain to get to the po installed a second one behind the generator panel near the transom and never replaced the one on the holding tank. Wondering if there is any down side to just eliminating the one on the waste tank and just keeping the one behind the panel?

 

[searay495]

Irie, so funny you just posted this. I need to replace my filter and was going to ask for suggestions on how to get to it. Does anything need to be removed to get in there, or just contort yourself?