Why is it HOT in Your Engine Room?

Hot summer afternoons create the need for air conditioning. What do you do when it's not keeping up?

Ten pm and my phone rings. Late night phone calls are never a good thing…

Lucky I had my new client’s number ID’d in my phone so I answered. First thing I heard was “Sorry to call so late BUT the air conditioners are not cooling and I hear a noise in the engine room. I went down there and it is hotter than earlier today and I did not run the engines. What should I do?” Did I mention he is in Florida… in the summer?

It’s Who You Know & WHAT You Know

A little background will set the stage for you. This new boat owner has literally just bought his perfect boat. He has not yet attended our two day Introduction to Boat Systems course. But, he has previously owned a boat – 20 years previous. I am scheduled to help them cruise their new to them boat from the purchase location to their new home port next week. They are aboard the boat a few weeks early to sort things out. He’s reviewing our Spare Parts list, checking on charts and other supplies before my arrival.

Being in Florida he and his mate want to enjoy the marina life for the weekend aboard their new toy. By their insurance rules they are not allowed to operate the boat until a licensed Captain could train and verify their competency – my role. But they are permitted to be aboard the boat to start their adventure. Of course, air conditioning is an important part of everyone’s summer adventure, no matter where you are.

What’s that Noise?

I hope you know the drill- what order of items to check and why. (If you don’t click here to learn about our Introduction to Boat Systems seminar.) First, find the noise and the source of heat. I asked him to listen and feel the electric water pump near the sea strainer intake and the outlet with a manifold of two or more discharge hoses. Found it.

Next, go to the alternating current circuit breaker panel to locate the air conditioner circuit breakers. Found them. He needed to turn off the Saloon, Master berth and Guest berth air conditioner circuit breakers. Done. Finally, he looked for the air conditioner water pump circuit breaker to turn off the pump itself. Found it and turned that off.

Know Before You Go!

This job can really get messy but a little bit of knowledge will go a long way. Therefore this is not the time to be watching a YouTube video, although it may have helped you to at least know what it looked like.

Next, get a bucket and bring it back into the engine room where the pump is. Then, follow the hose to the sea cock/through hull valve and turn it off. Open the sea strainer top and pull out the basket and check for debris. LOADED! It was full of YUK and that yukky debris restricted water flow to the air conditioner cooling water pump system. The rest is easy but yes, still a little messy.

Here is the WHY. I asked a few questions regarding the earlier part of the day. He said the air conditioners were cooling fine while they were cleaning the boat and exploring the different systems aboard. Later he noticed one air conditioner digital panel showed HP but did not know what that meant. I asked a few more probing questions then came out with the biggie, “Did you have a SCUBA Diver clean the bottom of the boat today?” Yes, why?

Unfortunately the diver did not ask the boat owner to turn OFF the air conditioner while he was scraping the sea life off the hull so the air conditioner cooling water pump sucked in everything scraped off the hull like a vacuum cleaner. The strainer actually did it’s job. Of course, all this debris clogged the strainer protecting the pump and thus no cooling water.

Understand What Your Equipment is Telling You

Why the HP reading? High Pressure occurs when there is not sufficient cooling and the Freon refrigerant in the air conditioning compressor overheats causing high pressure and the system shuts down to protect the compressor but the fan may continue to run blowing warm air.

Moral of this story

  1. Turn off the air conditioner when a diver is cleaning the bottom of the boat. (You may also want to disconnect the power but that’s another story for another day.)
  2. Learn what to know before you go cruising.
  3. Ask Captain Chris about basic owner maintenance in our two day classes in Vero Beach.
  4. Call 772-205-1859 and let us help build your cruising confidence.