Saturday, June 1, 2013

Water Circulation Woes...

As you may know we have been working on an engine room redesign/refit.  The start of this project was driven by the need to remove a rotted subfloor and add holding tanks.  To access all of this, essentially everything but the engine had to come out of the engine room and then start the process of rebuilding.

So the good news is we are really close and as we have been doing down this path, I have been planning how I would mount all of the pumps and strainers back in the engine room to make them easy to service.

The plan was to mount the water intake strainer for the engine and air conditioners on the side of the subfloor with easy access just sitting inside the doorway of the engine room.  I planned on using a single strainer for the air conditioner circulation pumps, so essentially water would come into the water strainer and then on the outbound side, I installed a tee fitting with one line going to the salon where the forward air conditioner water circulation pump is mounted.  The other side of the tee went to the rear air conditioner water circulation pump which was mounted in the engine room.

In the diagram below, Pump1 is mounted in the engine room and is a 1000 gallon per hour pump and runs water circulation for the owners state room air conditioner.  Pump2 is mounted in the Galley and is a 500 gallon per hour pump and runs the water circulation for the main salon Reverse cycle Air Conditioner/Heat pump

When we connected everything and ensured no leaks, we turned on the Air Conditioning in the main salon fed by pump2.  When the compressor kicked on, the pump did also and began circulating water and we had good discharge out the boat, I was feeling pretty good.  When we turned on the owner's state room air conditioner fed by pump 1, it would stop the feed of water through pump2.  I suspect this is due to being closer to the water strainer and also the fact that the pump is a higher capacity pump.  I really do not want to put another through hull in the boat so have at least come up with my next plan of action.

In the morning, I am going to remove Pump2, and just connect the lines together where the pump was.  I will then re-plumb the sea strainer to only feed to pump1, out of pump 1, I will locate a tee and feed water through both air conditioners.  The down side of this is that I need to either install a relay so that the pump kicks on when either Air Conditioner compressor runs, or I can connect Pump1 to it's own 110v breaker and just ensure that when either air conditioner is on, that breaker is on and the pump is running all of the time.

I do believe I may add valves to each output side from the pump so if I want to, I can turn off the water flow to either air conditioner if I need to service one without having to turn the other off.

I will be a little nervous wiring in the 110 volt pump to the breaker panel.  The good news is I can pull the shore power cord so I know that we will have no power coming into the boat while I am in there working on the back side of the distribution panel.  It should be a short cable run for the pump given it's proximity to the panel.  I will also need to disconnect the power to pump 2 from the inside of the Webasto Control unit in the forward salon.

Sadly, it looks like some more time in the engine room.  I don't mind it so much except after a few hours of being contorted into whatever position was required for the given job, I seem to end up with quite a few stiff muscles a few hours later.

All the while I was working on this today, Deb was sorting every single stainless steel screw, nut and bolt that I have managed to gather over the last 2 years of work.  She organized them all by size and put them in small waterproof containers.  She also sorted and organized all of the varied electronic, electric and plumbing spares and parts that we have on board.
In the last 2 weeks she has painted all of the bilges and storage behind the settees and the V-berth.  She started to organize and put the navigation station back together (we had relocated all of the items to another location when we rebuilt that).  She also cleared and organized the Galley and Tool storage.

June 2, 2013 - Update
The plumbing has been re-arranged and working as described above and outlined in the second illustration.  I opted for a seacock under the galley sink for the forward air conditioner rather than at the actual pump location.
Engine Room (Side of subfloor wall) | Left strainer for A/C and right strainer for Engine | Pump with split outputs