Marine Air heat on 330 express

ReelCatch

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Location
Newburyport, MA
Model
Express 330
Hey guys, I’m new to this forum. Currently in the process of purchasing my first GW 330 ex. When I went to run the a/c and heat I couldn’t get any heat out of the vents, just the fan would blow. A/C seems to work fine. Any ideas what it could be?
 
Was water flowing out the thru-hull? Did you open the seacock? It's a heat pump - basically the same as a heat pump in a house, but it uses water as the medium instead of of air.
 
the a/c seacock is open. I didn’t look to see if water was cycling out the thru hull, I will look next time I’m at the boat. Could the heat pump be bad or maybe a clog? Thanks for the reply.
 
At this point anything is a possibility - you'll know more after some further investigation. Truthfully, anything else would be guessing right now.
 
Also, look at the control panel - it will tell you if the electronics are saying that the heater's on or the A/C is on. Did you adjust the desired temperature high enough to kick on the heat?? Then check the water flow out of the lower port side of the hull - if the heat pump has failed, they are available and fairly straight-forward to replace. Another thing to investigate - is the seacock working properly?? If not exercised regularly, it could stress break and be the problem (it happened to me).
 
Thanks for the reply, yes I figured out how to get it on the heat mode vs A/C, you can heard what sounds like a pump turn on. The seacock valve is open or at least when I turned it on the quarter turn valve arm moves up. I will look next time at the boat to see if water is coming out the thru hull. Is the pump the same for the heat and A/C?
 
I didn't know that the AC system provided much heat. Nice to know.
 
I didn't know that the AC system provided much heat. Nice to know.
I should clarify, though, that MOST systems are a reverse-cycle. I don't know, but I "suppose" there are systems out there that are not - there by only being AC only. I can't say what's on the OP's boat at this point.

But, yes, they do a nice job with heat... until the water gets too cold of course :)
 
I'm pretty sure the AC on my 03 330 Express is the original, and it is AC only! (no heat option). There isn't a heat indicator on the control panel...
 
If the A/c is running and blowing cold air then it shouldn't be a water flow problem. The heat on my 305 works well. Keeps the cabin nice and toasty on those cold days.
 
any chance there is an ambient temp cut off? ie it will only heat if its below XX degrees outside/water temp? complete guess here
 
Hey guys, I’m new to this forum. Currently in the process of purchasing my first GW 330 ex. When I went to run the a/c and heat I couldn’t get any heat out of the vents, just the fan would blow. A/C seems to work fine. Any ideas what it could be?
If your ac works fine but you’re not getting heat in heat mode it could be a reversing valve .
 
If your ac works fine but you’re not getting heat in heat mode it could be a reversing valve .
exactly, AC working means the pump works and water is flowing or the air would not get cold. I have an '04 330 with original AC which cranks... tried heat one time last fall and could not get it to come on but I think I wasn't operating the controls correctly. They are a text book model of a control NOT being intuitive at all lol. I didn't put much effort into it as I don't use the heat... just wanted to see if it worked. I didn't even google it or look at the manual. maybe this fall now that it's a little Nipply out .
 
What type of AC is it? If it’s dometic the controller might be on P01( Heat only).
P00 = both cold and hot
P01=Heat only
P02=Cool only
Turn on unit via controller and hold power button for more than 10 sec. Indicator should illuminate the mode.