HVAC unit problem.

rinker312

All,  I had a problem last Sunday when I went down to the boat.  I turned the heat on, and got no heat, or water flow.  Week before heat worked great.  I turned the AC on, and it worked just fine and got water flow.  I have a friend across from me who is a HVAC specialist and he took a quick look at it.  he said that the reversing valve is kicking in (can hear it click when the unit switches over to heat), but the compressor and the water pump are not turning on.  Blower turns on also.  He doesn't know much about the marine units, but he suspects from looking at the manuals and some of the diagrams that the problem is with the thermostat unit.  Not sure why he suspects this because the thermostat is kicking over to heat and the heat light is turning on, but he thinks that little thermostat is controlling some of these other functions also.  I think the manual called it a passport or something like that.  Is anyone on here familiar with these units, or ever have a similar problem?  Any help would be greatly appreciated.  Thanks.

MarkB

Is your water pump primed?  The compressor won't kick on unless it detects water flow.  No water, no heat.

rinker312

Pump works fine. I switch to ac and got no problems. 

MarkB

OK. Do you have the manual, if not go online and look up your model. You need to know the program method and codes. I'm not sure this is the problem, as it worked in heat the week before, but worth a try. Check program code that sets to cool/heat/auto and ensure it is in auto so it switches to cool or heat based on temperature.  However, I am thinking there is a fault somewhere, maybe high pressure, preventing the compressor from coming on.  You can also call the manufacturer's customer support and they will provide guidance.

pepmyster

Had similar problems with mine, all kinds of weird stuff happening, talked to a hvac tech after I verified what I could, seems to be the mother board on the main unit itself. Removing the whole unit in the spring. Replacing with a new one.

rinker312

When you say motherboard.  Where is it?  Is it part of the wall thermostat assembly?  There doesn't seem to be anything like that attached to the unit itself

pepmyster

Correct, exact. The board is none serviceable.

rinker312

Just an update on this. A few weeks ago I called the company and got a service tech. He felt the problem was the programming in the thermostat. So I tried changing that and it didn't help. So after some messing around I accidentally held the button down too long and reset the factory defaults. That did the trick. Now heat and air are working fine.  

MarkB

LOL! Well that was a good mistake!

bella-vita

I had to prime mine last week first time using it this season worked great after that my machanic had to show me how to prime it

bella-vita

I had to prime mine last week first time using it this season worked great after that my machanic had to show me how to prime it

rinker312

For the first time ever I had trouble priming mine also after cleaning the strainer. How did he show you to prime it?  I got mine working but not sure if there is a better way.    Thanks 

rasbury

Have not had to prime mine yet.....would like to know how just in case!

Dream_Inn

You can prime by pushing water thru the external hull where it comes out (Just put the hose on it and pull the trigger).  Or you can simply go for a ride and that will prime it as well. 

bella-vita

Their is a  centrifical pump underneath the bed in the aft cabin which sucks the water in brings it to the HVAC motor there was air in the line he disconnected the hose from that pump let the air out only took a few seconds reconnected it  after that it was all good 

seguir

I had a air lock, all I had to do was turn on the A/C and unscrew the strainer a bit and it primed itself.

06Rinker270

I am having the same issues with the AC and Heat.  I dont think the AC will kick on because its too cold but I cant get the heat.  I am on Auto.  It starts on and then kicks off.  I got an HPF error last weekend when I tried AC.  Looked over manual and followed their troubleshooting steps but no go.  Took off the strainer.  Next I will try priming.  Does a HPF code come on if its not primed?

Handymans342

Yes you will get that code with no water flow.

Handymans342

You could also try taking off the discharge hose from the AC unit and blow air or water thru to make sure that is not clogged. 

06Rinker270

yea I should probably take off the hose that leads from pump to the AC as well.  It was just working before I took it out last November so I dont know how it would have gotten clogged unless something made a home for itself in the thru hull.  

Handymans342

I had mud daubers make a nest in some of my thru hull fittings. 

06Rinker270

I will give the priming a try this weekend and also push water through the pump discharge and the AC discharge. 

Also I noticed a small about of blue liquid coming out of the pump.  Think a seal might be leaking...

Handymans342

That may be the oil for the pump. I think the pump is oil cooled. 

JC290

on mine once i got the pump to take a prime i had to remove the hose at the unit coming from the pump just enough for it to push out the air and a little anti-freeze and been working like a champ. 

Stodge

I'm still looking for options with mine.  My display says it's 30 degrees warmer than it is.  And of course the Passport II are not easy to find any more.  I don't know if the issue is in the display or the board.  Murphy's law says which ever one (display or board) I replace will not be the problem.

JC290

Betting the board. Did you try resetting to factory settings and go from there

Stodge

Yes, and I unhooked the the air return sensor.  Even tried swearing. 

JC290

Well if the swearing didn't work I gotta say it's really broke lol. I will see if I can get answer for you but it won't be until this weekend

rasbury

if it displays the wrong temp, you can reset the ambient temperature. Mine had the same problem, it showed the temp inside at 67 so I could only set the air to 65- it would only cycle for those 2 degrees and cut off. Was sort of comfortable but the one day we went out when it was cold, darn thing about cooked us out. I reset my temp this weekend and man was it blowing some cold air!

Stodge

The temp setting you mention only allows you to go + or - 10 degrees.  I need to adjust it down over 30 degrees.

rasbury

If your talking about the temp of what the air temp is, you can change that to what ever you want- if you have your manual there are all sorts of changes you can make to the settings but be careful as when I was fixing mine, I did something where it would only heat- there is also a reset to factory settings option if you mess it up but the process is push on the power button and hold it, P1 comes up....I moved through to P5 I think it was and then I could set the temp for what the interior of the boat is to anything I wanted- as I said, mine was saying it was 65 degrees when it was 85!