Chiller troubleshooting

With a chiller system air temp readings at the air handler isn’t that important as it is completely dependent on the chilled water temp.

to cool the boat properly, it needs to be below 50 degrees and during the day all three chillers need to be on to get there.

One critical factor is sea water temperatures. When i run pump nr 1 with the new impeller above but eroded body, coil temps are 5 degrees higher than on pump nr 2, condition unknown.

Not a big difference in amps though , at most 1 amp per chiller, but it seems like the breaker holds longer

At this point, i need to get the pumps rebuilt or replaced.

Each pump and chiller has its own breaker inside the cruisair cabinet. For some reason Cruisair set up the whole thing to be fed by only two lines from the main panel.

made a few calls today, complete Scot pumps as well as head assemblies are back ordered. No eta. Going to try the spare I have on the 84. Same model

Update.

i replaced one of the two sea water pumps with a rebuilt one 3 days ago and so far so good. The breaker hasn’t tripped and I have been able to get the loop at a constant 47.5 to 49 degrees since. Makes a big difference inside the boat. Obviously

i m having another spare rebuilt as well and will swap it for the second pump, which I suspect also has a lot of erosion.

Breaker has been holding fine till last night after returning to dock. Quickly realized that the middle coil on chiller nr 2 was much hotter than the others. Each chiller has three coils.

back flushing the whole chiller didn’t help has the water took the easy path they the other coil. Disconnected that coil and sure enough... this came out.

In this case the coil was so hot that just touching them revealed the issue but other wise an IR Gun is a great tool. A few weeks ago I wrote the temps on the coils to have a baseline. Very useful.

Strainer basket had a small crack. It’s a plastic groco. I m ordering a new one and in the meantime used a zip tie to close the seam.

next haulout I am putting an external strainer on the air con. I ve had them on my own boat for 3 years now they work great. I m in the next slip and no issue with stuff coming on and no strainer to clean.

They re also called South Bay strainers. Instead of having wide slots, they have a bronze mesh which is removable and replaceable in the water (diver). The mesh prevents stuff from being ingested. Works really well.

Air runs 24/7 inches under way. I installed the same type for the mains when I repowered. No issues.

I ve instructed my diver to brush them every month.

The crap the diver shakes loose is so small (fitting thru the mesh) that it s no worries.

I ve been using these for years on various boats and it s been great.

another issue with slots is that plastic bags get stuck in them and don’t come off unless you go remove them... usually on a Sunday morning at 7am. Used to happen at least twice a year. With the mesh as soon as the pump shuts down, the plastic bags floats away.