How is an AC water pump connected to 3 Units?

[The Brockerts]

I have 3 split systems 16K btu AC units on my 48 Californian. They all run off the same paragon Sr Water pump. Each of the AC units have a controller board with a "pump" hot wire on a wire bus bar.

My pump has 1 wire, standard 10ga (white/black/ground) coming in so somewhere the 3 pump wire's are connected somehow.

Are all 3 of these hot "pump" lines just connected together somewhere or are they connected to a relay/switch?

I've trace these lines from both ends the best I can so far. Any additional tracing will require some serious digging and remove of stuff. I'd like to know how or what I'm looking for before digging any more.

This project falls under the description of "I need to know how my systems are working" as everything is working just fine.

If there is a switch/relay or some component involved then I need to have an extra on board as this boat is 32 years old and the pump is the same.

As a side note: I've added a vent for the Paragon Sr. pump since that pump puts out a lot of heat in my engine room. It cooled the engine room down 12-15 degrees and in South Texas heat every degree helps.


The Brockerts

 

[Tomas]

I have a 2 compressor split system. The pump and each compressor are connected to the pump relay. The compressor for the Salon is the master and the other is the slave. The pump relay is powered by the Salon unit and it must be on for the Stateroom unit to work.

 

[DavidM]

A/C systems with more than one compressor and only one pump, usually have a separate relay that controls the pump. As you note, it takes a good size pump to supply three 16,000 btu units.

David

 

[The Brockerts]

Ok, I'll continue to dig now that I know a relay is somewhere in inline, and it's just waiting to fail.

Yep, that pumps is putting out around 11 gal per minutes at 32 years old....wow

The Brockerts

 

[Bmarler]

I would think there would be a relay from each unit. They are likely located on the units them selves. Each relay output would be a parallel path to the pump. I’d start at the pump and work toward the ac units. Shouldn’t be too hard to see how it’s all connected.

 

[Porgy]

I don’t know what system you have but, here is an example of a Dometic pump relay. The wiring diagram is inside the outer cover shown removed. All three A/C units tie into it from their control boxes and it’s within a couple feet of the pump.

 

[The Brockerts]

Progy, The majority of my system is Dometic. I've got a box that looks very similar to that, unfortunately its behind a hot water heater and I've can't easily get to it. Now that I know it could be the relay I'm looking for it I'll see if I can track wire's to and from it before trying to move the hot water heater.

Thanks for the pictures !

The Brockerts

 

[The Brockerts]

Progy, The majority of my system is Dometic. I've got a box that looks very similar to that, unfortunately its behind a hot water heater and I've can't easily get to it. Now that I know it could be the relay I'm looking for it I'll see if I can track wire's to and from it before trying to move the hot water heater.

Thanks for the pictures !

The Brockerts

 

[OldDan1943]

One pump for 3 A/Cs? I hope you carry a spare pump.