Low Pressure message

[Dan Leff]

I have a 40' Sea Ray Sedan Bridge with 2 AC systems. The first system in the salon heat works fine with no problems. I keep getting a low Pressure warning on my master stateroom system. I have cleaned out the strainer but am still having the same problem. I have a couple of questions. I believe that both systems share the same strainer. If that is the case, which I expect, why would the salon system not be showing that same warning. Water temp shouldn't be a problem as its above 50 degrees. I have changed the air filter but don't think that would be causing the problem. Could there be a clog somewhere in the waterline to that system. If so, what would be best way to clear that. I'm pretty handy but this is my first boat with an AC system. Any suggestions greatly appreciated.

 

[Jaybeaux]

Try this thread.....

http://www.clubsearay.com/index.php?threads/cruisair-ac-had-fault-message-lo-ps.24062/

 

[RBB]

U sure you sure your system dosen't need charged. Thats what I think the low pressure
reading is. Is it showing on the control for the unit? If so it needs charged.

 

[Dan Leff]

U sure you sure your system dosen't need charged. Thats what I think the low pressure
reading is. Is it showing on the control for the unit? If so it needs charged.

Its a closed system so if I need a charge I would have a leak. Just trying to check every other option before getting someone out to look at it. Could a clogged water line cause the low pressure?

 

[RBB]

being several years old most need a charge to get the job done.
look at your a/c water discharge flow on the outside of the boat. If the flow looks low or weak just back flush with a dock hose couple times.

 

[Dan Leff]

being several years old most need a charge to get the job done.
look at your a/c water discharge flow on the outside of the boat. If the flow looks low or weak just back flush with a dock hose couple times.

Thanks, flow is good out of both water discharge holes. Looks like I will have to get someone out to check for a leak and recharge. Thanks

 

[RBB]

It being low on which ever gas it uses dosen't necessarily mean you have a leak. After several years
its a common thing. Shouldn't take a guy 10 minutes to top off. My guy dosen't even hook up gauges
just feels the air coming from the unit.

 

[Dan Leff]

It being low on which ever gas it uses dosen't necessarily mean you have a leak. After several years
its a common thing. Shouldn't take a guy 10 minutes to top off. My guy dosen't even hook up gauges
just feels the air coming from the unit.

Great, Thanks for you help.

 

[R-and-R]

This might be worth trying. Quite possible you have a partial blockage in the raw water system for the Master Stateroom A/C.

 

[Dan Leff]

This might be worth trying. Quite possible you have a partial blockage in the raw water system for the Master Stateroom A/C.

Thanks for the help. I did flush the system and had great water flow. I spoke to the former owner and he recommended pulling the control panel off and check the connection. I unplugged and plugged it back in. Works fine now with no low pressure readings. Not exactly sure why but it may have just been a loose connection. Has worked fine for the last week so hope that was all it was.

 

[ttmott]

Loss of raw water flow will generate a HiPs error not a LoPs error.
That LoPs error is the pressure switch for low compressor head pressure is tripping which means that the raw water temperature is too low to generate heat or you have a loss of refrigerant.
It could also be a combination whereas your refrigerant level is below the other unit on the boat and just low enough to trip with the cold raw water.
So, if the other unit is heating ok then I would say you are a bit low on refrigerant.

 

[Henry Boyd]

Dan,
Differing performance by the hvac units using the same strainer is very possible. We have four compressor units with four air handlers all running off the same strainer and raw water pump exiting through two through hulls. We had a plug in one of the branch cooling lines that shut down the front cabin while the helm and main salon were all running fine.

We have the Dometic Marine Air AIRRRRRRRR system. To switch between heating and cooling, the system has a shuttle (or poppet) valve that reverses refrigerant flow direction. On our model system this valve has a tendency to stick if heat is not used often enough. On ours the valve is located on the compressor unit and can be unstuck by rapping it with the handle is a screwdriver.