Can you adjust chilled water temp on a Condaria aircon unit?

[Deleted User YDKXO]

My boat is fitted with a Condaria PCWM/FCL 12002 chilled water aircon unit. The temp of the chilled water is shown on the remote control panel and this never falls below 10degC. In fact the compressors seem to be set to cut out when the chilled water temp reaches 10degC and the indicated chilled water temp seems to range between 10degC and 12degC. The user manual for my boat states that the chilled water temp should vary between 7degC and 11degC but says nothing about adjusting the temp at which the compressors cut out. Unfortunately I dont have a user manual so I dont know how to adjust the cut off temp.

Anyone got any idea how to do this?

 

[Assassin]

I believe you can, but not sure how so cannot help here.

I believe Dometic took over Condaria and usually Dometic put their manuals online in their technical or user manuals section, so maybe worth a look.

 

[Mr Googler]

I certainly could on my (no doubt) older condaria.

There where 2 dials inside the main box on the chiller itself. One for min temp in air con mode and one for max temp in heat mode.

Old fashion dials. Turning the pointer hand in the centre with a screw driver adjusted the temp the compressor / sea water pump cut in and out at.

 

[Deleted User YDKXO]

I certainly could on my (no doubt) older condaria.

There where 2 dials inside the main box on the chiller itself. One for min temp in air con mode and one for max temp in heat mode.

Old fashion dials. Turning the pointer hand in the centre with a screw driver adjusted the temp the compressor / sea water pump cut in and out at.

Thanks. I did read on another forum that there were adjustable dials inside the electrical box but I checked inside my electrical box and there are no dials of any sort. There are 2 components which look like relays with pin type adjusters on the back but I dare not fiddle with them without knowing what I'm doing. I have searched the internet for a user manual under both the Dometic and Condaria brand names without turning up anything which is surprising because these are commonly used units particularly on Italian boats. Btw my boat is 12yrs old and I assume the Condaria unit is original

 

[Mr Googler]

Drop Edd an email

edd@midshipboats.co.uk

He’s Condaria UK agent. Super helpful guy...really good.

Mine was installed 1988.....he found lots of useful stuff like full wiring diagrams.

12 years old is brand spanking by comparison

 

[Deleted User YDKXO]

Thanks I'll try Edd

 

[MapisM]

the compressors seem to be set to cut out when the chilled water temp reaches 10degC and the indicated chilled water temp seems to range between 10degC and 12degC. The user manual for my boat states that the chilled water temp should vary between 7degC and 11degC

M, I suppose you mean the generic Ferretti manual, dontcha?
I'm asking because I've got the very same equipment on the DP (just a bit smaller: PCWM/FCL 9002, rated for 36k BTU vs. 48k of yours), and I can very rarely see a temperature under 9 degrees, where both compressors automatically cut out.
So, it seems that there's just 1 deg difference between your cut out temp and mine, which makes me wonder where the 7deg comes from.
Btw, the system is VERY effective in my boat: in a few occasions when I only had a 16A dockside connection available and I switched off one of the two compressors, it was still fine - just a bit slower in cooling down.

Anyhow, I also don't have any technical manual, and I'd be interested to keep one in my files, if you manage to find it.
If you can't, gimme a shout. I could try to ask it to a chap who services these things.

 

[Deleted User YDKXO]

M, I suppose you mean the generic Ferretti manual, dontcha?

Yup thats where the 7 - 11 degC range comes from. My system actually works fine but because the saloon is so big and like a greenhouse, the compressors are working continuously chilling the water to try to maintain the set temp. I'm hoping that if I can adjust the cut off temp lower, the chilled water will be colder, the saloon temp setting can be maintained better and the compressors work for less time

 

[Portofino]

My Frigomar chiller circulation water temp is 7 .
We have a digital display on the outside of the unit which shows that .
42 K btu .circa 2014 .

In humid times condensation forms on the outside of the lagged pipes ( obviously on any thing unlagged like the circulation
Pump itself .
So far no issues .

But I hear some have condensation issues of the connecting pipe work ,depending how ventilated the spaces are .
Cooling theses more will make that worse .
For clarity this not condensation from the air handler coolant matrix pipes ,thats normal and collected in the drip trays .
This is on the outside of the lagged pipes connecting the air handlers chilled water to the compressor.

Just something to be aware of if you are considering turning it down even more .

 

[MapisM]

the compressors are working continuously chilling the water to try to maintain the set temp.

I see your point, particularly ref. your greenhouse-like large side glasses.
Otoh, I wouldn't hold my breath ref. any practical difference you could achieve, assuming that the cut out temp can be lowered.
If in hot weather your compressors are already working continuously, by definition they couldn't cool further the closed circuit water, irrespective of the cut out setting...

 

[MapisM]

42 K btu

I guess it must have been retrofitted, reasoning along the lines of better safe than sorry...
42k BTU for your boat sounds way OTT, when compared to 36 on my DP and 48 on a F630!

PS: for the records, I had 17x2 on my old lady, whose internal volumes were just slightly smaller than the DP, just as another example.

 

[Deleted User YDKXO]

But I hear some have condensation issues of the connecting pipe work ,depending how ventilated the spaces are .
Cooling theses more will make that worse .
For clarity this not condensation from the air handler coolant matrix pipes ,thats normal and collected in the drip trays .
This is on the outside of the lagged pipes connecting the air handlers chilled water to the compressor.

Just something to be aware of if you are considering turning it down even more .

Thats a fair point L. Quite obviously somebody has set the compressors in my aircon unit to shut down at 10 degC rather than a lower temp. The question is why and you may have hit on the reason. The condensation from all 7 air handlers on the boat flows to a small sump under the master cabin which is cleared overboard by a bilge pump. We are regularly disturbed at night by the noise of this bilge pump kicking in when the aircon is on. It could be that the previous owner of the boat has increased the chiller water temp to 10 degC in order to reduce condensation and reduce the operation of this pump?

 

[Deleted User YDKXO]

If in hot weather your compressors are already working continuously, by definition they couldn't cool further the closed circuit water, irrespective of the cut out setting...

Not sure thats correct. I am watching the control unit right now. One compressor shuts down at 11 deg and then both shut down at 10 deg and the sea water pump also then shuts down. When the chilled water temp then rises to 11.5 deg, one compressor starts up again with the sea water pump and then at 12.5 deg both compressors start up again and the process repeats itself. If I can get the compressors cycling between, say, 7 deg and 9.5 deg then I'm sure it would make a difference to the saloon cabin temp

 

[MapisM]

Hang on, that's different from what you said ref. "the compressors are working continuously".
Which can happen, mind. Depending on external and also sea water temp, it is quite possible that the system runs so close to its max capacity that the compressor(s) must keep working.
Besides, are you reaching your desired temp inside, or not?
In my system, whenever the internal thermostat(s) reach the temp, it's the air handler(s) that goes in standby (i.e. fan goes off), but the compressors keeps working (or not) depending only on the cooling water temp - which usually is anywhere between 8.5 and 11.5, leaving aside the startup when it can obviously be much higher.

PS: as an aside, how can you tell when the raw water pump goes off? Do you have a telltale? The control panel doesn't tell you that, afaik.

 

[Portofino]

That’s the whole negative issue with ac ( as in current) powered AC ( as in Aircon ) .
The comps switch off and on to regulate the circulation water temp to the air handlers.

With the comp ( s) off there’s no need for the sea water cooling hence that s intermittent too , the pump(s)

Seperately the air handlers fan speed can vary too or maybe switch off .


Now with a D.C. ( as in n current ) Aircon comp motor ,It never switches off just slows down when deemed temp is reached and thus the seawater pump is running constantly too .This the USP of the Frigomar D.C. 410 systems .
They come in modules either 42 or 62 K btu .We have a retro fitted 42 .
View attachment 72915
View attachment 72916
Fitted under a bunk it’s also so quiet the occupants don,t know it’s running .

Air handlers just vary fan speed if the system is on auto ,but you can also like a car AC adjust the fan speed too .
Because every component is always running never off - comp , pumps air handler fans etc there’s no start up spikes .
Additionally there’s an “eco mode “ when this is pressed the power drain is reduced by 50 % and interestingly for Mike the circulation water temp is allowed to rise to say 10 from 7 .

So I think if Mike can find a way to shave off a few degree s off the circulation water temp then it will cool more the airhandlers .
You need to set the cabin temps to low ish so the system can chase it down ,that way it should not shut off easily .
Ie 18 when it’s 36 really inside .

If you are on dodgy shore power and have other power hungry AC stuff on while the comps/ pumps have turned themselves off then they may struggle to restart if conventional ac ( in current) due to spikes .
This could lead to somthing tripping
On the boat or dock either way hassle . This does not apply to the Frigomar system as it never switches off and when on runs at a ridiculously low amps due to the comp being dc powered not ac.

 

[Deleted User YDKXO]

Hang on, that's different from what you said ref. "the compressors are working continuously".
Which can happen, mind. Depending on external and also sea water temp, it is quite possible that the system runs so close to its max capacity that the compressor(s) must keep working.
Besides, are you reaching your desired temp inside, or not?
In my system, whenever the internal thermostat(s) reach the temp, it's the air handler(s) that goes in standby (i.e. fan goes off), but the compressors keeps working (or not) depending only on the cooling water temp - which usually is anywhere between 8.5 and 11.5, leaving aside the startup when it can obviously be much higher.

PS: as an aside, how can you tell when the raw water pump goes off? Do you have a telltale? The control panel doesn't tell you that, afaik.

Well I didnt want this thread to become a discussion on the general operation of my chilled water aircon system! When I said that the compressors were operating continuously what I meant was that they were cycling continuously, I have set the desired temps on all the air handlers on the boat at 23 deg. During the middle of the day at least, the actual temps shown on the saloon air handler control panels never gets anywhere near that (often high 20s at best) although the temps in the cabins are lower. So the saloon air handlers are working continuously during the day and never shutting down which means they are continuously calling for chilled water. Yes there is a tell tale on the main aircon control panel in the saloon showing when the chilled water circulation (CP) pump is operating and I can see that it operates continuously during the day. So the saloon air handlers are continuously calling for chilled water because they can never reduce the saloon temp to anywhere near 23 deg during the day time. That in turn means that the compressors are continuously going through their cycle producing chilled water

So what I'm thinking is that if I can reduce the chilled water temp that will mean that the saloon air handlers have more of a chance of reducing the saloon air temp to 23 deg and therefore shutting down. I dont for one minute believe that by reducing the chilled water temp, I can maintain 23 deg in the saloon all day and every day but if I can reduce the amount of time at the beginning and end of the day when the saloon air temp is above 23 deg, then the air handlers will be shut down for longer. Also, for those nights when we leave the aircon on in our cabin, I am hoping that a lower chilled water temp means less cycling on and off of the air handler and less cycling on and off of the compressor units as well which will mean a better night's sleep

 

[BartW]

hi Mike, fwiw

on my 29y old airco (also Condaria iirc) there is a box with mechanical gauges on top side, right between the two compressors,
there are also electric wires coming out of that box going to the big electric controll box,
so I guess there are the thermostats for the compressors.
this box and the gauges are only visible and accessible after taking away a top cover plate,
I'll check next week if I can adjust the compressor temp setting there (good idea by the way)
but we are a lot less sensitive for the higher temps than you brits, thats why we go to the med ;-)

 

[Mr Googler]

hi Mike, fwiw

on my 29y old airco (also Condaria iirc) there is a box with mechanical gauges on top side, right between the two compressors,
there are also electric wires coming out of that box going to the big electric controll box,
so I guess there are the thermostats for the compressors.
this box and the gauges are only visible and accessible after taking away a top cover plate,
I'll check next week if I can adjust the compressor temp setting there (good idea by the way)
but we are a lot less sensitive for the higher temps than you brits, thats why we go to the med ;-)

I think you’ll find that box is the high and low pressure cut out control for the high and low sides of the compressor. Reset switch there too. Was on mine from the same era

 

[vas]

mike,

I think the problem with condensation wont be on the airhandler exchange units (or whatever you call them) but on the pipes themselves (I think PF pointed that out)
You may end up with water running down bulkheads or whatnot (not familiar with the pipework on the Ferretti!)

further if I may say so, 23C is WAY TOO LOW, but I understand you cold blooded northerners want it that way.
It's beyond me how you survive the aft deck day time temps though

All around my house and office stats are at 27C or 26 the least (if I bother to turn it on that is). mind I never sleep even at home with aircon on. We had a family of Danes this summer and they immediately got it down to 22C and didn't manage to persuade them...
Boat I don't bother except for half an hour in the evening sometimes in marinas to cool the cabins (once in 15days this summer).

cheers

V.

 

[MapisM]

I am hoping that a lower chilled water temp means less cycling on and off of the air handler and less cycling on and off of the compressor units as well which will mean a better night's sleep

I'm afraid you might achieve the opposite result, if you think about it.
The fact that the central machine reaches its operating temp and cycles frequently indicates that it's doing its job nicely, if we leave aside the water temp for a minute. In spite of that, the air handlers can't bring the internal temp down to your desired level.
Btw, if that's what happens, waddumean "less cycling" of the air handlers? They are bound to run constantly, i.e. with no cycling at all.
Regardless, in this situation, the air handlers are to be blamed, imho.
Are you sure that their filters aren't clogged, restricting the air flow?
Alternatively, the units might be undersized and/or badly placed, but that's not the sort of corner cutting that I would expect from Ferretti.

Anyway, let's assume that the filters are ok, and for some reason the circulating water temp is set too high.
Let's also assume that by lowering it you get a more effective cooling - possibly reaching the 23deg (or whatever) that you wish to have.
The result is bound to be that the air handlers would cycle MORE than before, not less!
Otoh, possibly the compressors might need to run more constantly, hence cycling less.
But I suppose that the more annoying inside noise is from the air handlers...
Or can you hear the compressors from the main cabin even if there's the crew area between it and the e/r?