Aircon and sump cleaning advice

Andy Bav

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kent. Boat in Sant Carles
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We are really enjoying the boat, and in this heat the air-con has really come into its own. We left her in mid July, and are back on her now, but noticed that there is a slight smell (not pungent by any means, just a noticeable background "whiff") in the air when the aircon is on - basically 24 hours a day. Having never had aircon before I wonder if there is any recommended regular maintenance I should be undertaking to keep the system fresh and clean. The filters were cleaned yesterday.

I also note that one shortcoming of a V42 is that all water waste is pumped overboard via a bilge pump in a sump. The sump that jointly collects the sink waste and the mid cabin shower water is very dirty, which I think is contributing to the smell. The challenge I have is getting any cleaner to stay in the sump for any period of time, as the float switch empties it. I will isolate the fuse to the sump pump and pour some bilge cleaner - which in Spain looks like Jeyes Fluid - into the system, and leave for 10 minutes or so, and then flush with fresh water. Do the collective think that Jeyes Fluid would be too harsh / corrosive for such an operation ?
 
AC should have a drain pan under the units .
This should be drained away into a sump box or bilge .If bilge find out which one ,if they are segregated .
Alternatively the units may just have a try which kinda collects a little condensation., but not really designed to fill up in normal operation .
Either way it could be the liquid under the units ,evaporating off when you left and now forming a sludge/crud of basically micro organisms -smelly bugs picked up while the air circulates --off the boat users .
They have now multiplied in the heat /moisture .
So the plan of attack is antibacterial ,- viruses and spores don,t smell .
Add some thing like dilute detol , corsodyl mouth rinse ,or toilet duck .
Pour it carefully down the side of the unit into the pan (s)

Be careful adding bleach agents due to risk of corrosion .

With regard to stationary sump boxes left in the Med-agian last thing before you leave pour a dilute antibacterial .
A few weeks soaking will keep the nasty bugs away .
Pour a bit down the sink /shower u bends too

When you return everything will be nice n fresh .
Corsodyl mouthwash comes in mint flavour too .
 
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We are really enjoying the boat, and in this heat the air-con has really come into its own. We left her in mid July, and are back on her now, but noticed that there is a slight smell (not pungent by any means, just a noticeable background "whiff") in the air when the aircon is on - basically 24 hours a day. Having never had aircon before I wonder if there is any recommended regular maintenance I should be undertaking to keep the system fresh and clean. The filters were cleaned yesterday.
I presume you have chilled water type aircon with the compressor unit in the engine bay which distributes chilled water to air handlers around the boat? The air handlers normally collect air from a vent low down in a cabin, pass the air through the chilled water heat exchanger and then blow the air out through vents high up in the cabin. IMHO the only way that the cabins can get whiffy with the aircon working is if the air handling system is picking up whiffy air from the bilges. You say you've cleaned the filters. Which filters? The filters on the air intake side? Have you checked that the pipework between the intake vents and the heat exchanger is properly fixed and not drawing air in from the bilges. Might be worth checking the actual heat exchangers, if you can, to see if there is any mould growing on them. Ultimately if your bilges are fresh and the air in the boat is fresh there should be no reason why the aircon air is whiffy

I also note that one shortcoming of a V42 is that all water waste is pumped overboard via a bilge pump in a sump. The sump that jointly collects the sink waste and the mid cabin shower water is very dirty, which I think is contributing to the smell. The challenge I have is getting any cleaner to stay in the sump for any period of time, as the float switch empties it. I will isolate the fuse to the sump pump and pour some bilge cleaner - which in Spain looks like Jeyes Fluid - into the system, and leave for 10 minutes or so, and then flush with fresh water. Do the collective think that Jeyes Fluid would be too harsh / corrosive for such an operation ?
Not sure thats going to do any good. In fact it might damage the pipework if you do it too often. Also its probably against the marina environmental regulations. Take the top off the sump and clean it out by hand with a sponge and soapy water. In fact in time you will probably have to do that anyway because the float switch will get clogged with detritus and stop working or if its a magnetic type get coated with slime. Sorry its a horrible job but all the solids that drain out of the shower (eg hair) and sink will collect in the sump and eventually stop the float switch working so get in there and make sure its totally clean and free of solids and slime. I clean the sumps on my boat once a year and nobody else volunteers to do it:disgust:
 
Thanks for the comments - it was the air intake side that was cleaned (actually, I am not on the boat until the weekend, but the wife is and a good friend had that pleasure of doing that task :-)) ) They also sprayed a very diluted Milton solution in the air intakes - which I guess is along the lines of the mouth wash solution suggested. The heat exchangers looked clean when I looked at them last (July).

As regards the sump, I was trying to avoid MikeFs obvious solution :ambivalence: - but I guess that's the only way. I have bought some antibacterial solution (which was ridiculously expensive) and I think I may give that a try before entering the dark world beneath the berth. I have already replaced the forward cabin shower sump pump, that was not so bad as it only contained shower water, but the rear cabin sump services the mid cabin shower AND the kitchen sink - that is likely to be a whole different story. Wish me luck ! :disgust:
 
It could be worse. You could be having to take a blocked toilet apart;)
 
Milton,s a dilute hypochlorite --it's bleach a no no where metal is concerned .
Ok ish once in while but repetitive use = corossion ,it especially like crevices of stainless steel .
It's for plastic none metallic stuff ,potties, baby bottles etc
 
For the drain sump .
Perhaps try a toilet cistern block in the pump sump.
Alternatively a slug of toilet blue with some clean water introduced via the shower or sink outlet.
 
I had exactly the same issue, washed out the shower sump and all is hunky dory.

I'll monitor it and wash out as required and flush through with fresh water before I leave for any length of time.
 
A small amount of a simple biocide added to the AC drain pans before you leave the boat will sterilise any stagnant water puddles. Not much will be needed, and I would use some ordinary household bleach watered down say 4:1. If you can get to the cooling coil a thorough spray allowed to drip down into the drain tray will clean out any dust or dirt gathered on the coil too.

Spa shops also offer biocides that are very effective on water borne contaminants and will be harmless to stainless steel and other metals. Because these are intended to be used with quite high volumes of water they are quite cheap for the tiny quantities that will be needed.

For those using chilled water that will sit stagnant and warm when the boat is not in use a suitable biocide should be added to the water circuit too. Stagnant water = Legionella = very unpleasant and sometimes lethal Flu like illness. Shower heads are also a breeding ground for legionella, so an occasional soak in bleach is also a good precaution.
 
Thanks for all you responses - very much appreciated.

As this boat has more complicated systems than the Bavaria, its clear I need to re-adjust my regular domestic maintenance regime - especially when she is sitting in 39 degree heat - so very useful tips all round
 
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