Marine Air heat on 330 express

ReelCatch

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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?
 

DennisG01

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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.
 

ReelCatch

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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.
 

DennisG01

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At this point anything is a possibility - you'll know more after some further investigation. Truthfully, anything else would be guessing right now.
 

loubeer

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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).
 

ReelCatch

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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?
 

Fishtales

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I didn't know that the AC system provided much heat. Nice to know.
 

DennisG01

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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 :)
 

everwhom

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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...
 

drbatts

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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.
 

Ekea

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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
 

Half-Lit

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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 .
 

Automated14

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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 .
 

LadyG

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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.