running the air conditioning on the trailer

duane.mosley

do they make a plunger type attachment for the through hull water pickup ? i need to trouble shoot my air conditioning and would like to do it in my driveway on the trailer if possible. when on the water this past weekend, we verified that the water pump is working and the fan comes on but not the compressor.

Cableguy Greg

It is called 'fake a lake'.

http://www.amazon.com/Alloy-Marine-Products-FAKE-A-LAKE-Inboard/dp/B00280COZO/ref=pd_sxp_redirect

duane.mosley

thanks.

duane.mosley

i have the marine air 7000 btu unit, model vcd7k/2. when i turn on the air, the water starts pumping, you hear the compressor kick on and you can feel it getting hot, but the air coming out isn't that cold. does that unit have to come out to be serviced? how much of a pain is it to get that unit out of the hole? i have a 2006 250ec and it is in the aft sleeping berth tucked under the helm seat.

MarkB

Maybe just needs gas recharged. 

raybo3

If it needs a shot of Freon then it has a leak. You should try to fix the leak then get it charged.

duane.mosley

So short answer is take the unit out. Freon doesn't evaporate so in order to check everything and be able to fix the leak, it has to come out. That's sounds like fun! Lol  I can only see two of the mounting brackets. I know there should be one on each corner so I'll just have to feel around for the other two. 

how long should that control wire be? I'm sure I'll need the control unit connected in order for it to function properly. Not sure my HVAC guy is going to want to crawl into the aft cabin, even though it's a lot cleaner then most places he goes. It is tight in there to try and work. 

duane.mosley

is there a way to bypass the control wire so i can pull the unit out of the boat and into the garage to service it?

duane.mosley

raybo3, here's one for ya. i have been doing my own mechanic work for over 20 years. i bought my own vacuum pump and gauges to do my own ac several years ago. i understand that freon doesn't evaporate and if it's gone, there is a leak(99.9% of the time, this time being the 1%) . i pulled my unit out of the hole that it was in and brought into the garage. there was no freon in the system at all. first thing i did was take my mightyvac pressure/vacuum gauge to apply pressure so i could do the soapy water test to find the leak. the pressure reading didn't budge! 15lbs first time for about 20 minutes. then bumped it up to 25lbs pressure and still didn't budge for 20 minutes. so i said what the heck, lets do a vacuum test. pumped it down 15inHG and let it sit for 20 minutes, didn't budge so pumped it down to 25inHG and the same results. so i put the motorized vacuum pump and proper gauges on the system and let it run for about 5 or 6 minutes.  pulled the system down to 25inHG bout an hour ago, and the gauge hasn't budged. so after spending a couple of hours doing several tests, i would say there is no leak in my system.  most of my experiences, all with cars of course, when the freon is gone there is a leak. i am really puzzled as to where the freon went.  i am going to pump the 10oz of r-22 the system calls for and see what happens.




what really stinks, i had a bad o-ring in the low pressure side of my dual gauges. if the o-ring would have been good, i would have realized that the system was holding vacuum without having to take it out!  after i used the hand pump and it didn't bleed off, i started investigating my dual gauges and replaced both o-rings in the high/low valves. holding steady like a champ now. oh well, just another aspect of our new boat that i got to figure out. i'll let ya know how it goes once i get some r-22

raybo3

Wow never heard that one before. Question is it possible that the shrader valve is leaking and you cant find it because the gauge is now hooked up to it???? It had to go somewhere.....LOL

duane.mosley

good point!!! that would be the only thing left. with the gauges connected, the valves are open so therefore not showing signs of leak. it would have to be the low pressure valve that is leaking. when i did my hand held pressure and vacuum test, i was using the low pressure valve, the high pressure valve was closed. i will switch tests and use the high pressure side just to see if that was it.  i will replace both valves before i proceed just in case.  thanks, that's why this forum rocks!!

raybo3

Good luck and keep us posted......

MarkB

That's exactly what I was thinking. Your connection must have been the piece that was leaking.

duane.mosley

I finally have cold air conditioning. I charged the system and replaced the water pump. I fell asleep on the boat watching the control unit waiting for HPF to kick on. Hour and half later I woke up cold, 66 degrees in the boat! Thanks all! 

raybo3

Glad your cold. 

Dude_Himself

What Marine Air unit was this, and what fittings did it have? I have a similar dilemma... got gauges, R-22, and a turbotorch. I'll buy a vacuum pump if it's something I can fix.

rasbury

that's one for the books, still say it was that valve and probably taking the gauge on and off messed with something in it and now it is holding as it should...has to be!

duane.mosley

only conclusion that we could come up with, the water pump was not pumping enough volume of water over the coil. due to the lack of water, it created high pressure in the freon line. the high pressure caused a leak through the schrader valve. it has worked the just fine since the new water pump was installed and the system was recharged.

dometic marine air 7000
the high and low pressure fitting where just normal schrader valves. my residential HVAC guy put his gauges on and carged the system. it has worked just fine since.

jhofmann

Where can you get R-22? All I can find is R-134A.

Handymans342

Online

Dude_Himself

jhofmann said:

Where can you get R-22? All I can find is R-134A.

I have 20# from back in the day for my residential HVAC, but the system, once I worked it over, hasn't leaked again since. It's quadrupled in price since.

Dude_Himself

Picked up one of these today - now I can flush the AC/Genny via the through hulls.

Handymans342

Nice

duane.mosley

i just bought a cheap plunger from home depot and put a female hose receptor on it. cost around 5 bucks and works great. i just used it again last week to test my ac before my weekend trip to the lake.