AC update questions (bear with me)

[Whitelighter]

Seralia has the orginal AC system fitted in the mid 90s by Condaria (now part of the Dometic group).

The system works (yay) but is quite low power by modern standards.
The big issue is the fans in the cabins are very noisy and while I know I could spend £20,000 on a whole new system Id rather not.

The system is a split (is that the right term) system which has the following components:

In the engine bay there is the compressor unit which has the raw water inlet and the heat exchangers to heat/cool the circulated water.
In each cabin there is an air handler to which runs the refrigerated water (not coolant, deffo water).

The system isn't smart. The compressor unit is either on or its off, and it just keep the circulating water at a set temp (8C in summer, 25C in winter)
The air handlers in the cabins are either on or off, with two fan speeds (loud and very loud). The air handlers and the compressor bit DO NOT talk to each other.

I can run the air handlers with the compressor off an vice versa.

What I cant believe is the handlers were designed to be this noisy. What Id like to do is upgrade them to quieter more efficient units that provide more cooling. I am assuming bigger handlers might achieve this.

Last I spoke to Dometic they just wanted to sell me a £20k digital new system.

Any thoughts?

 

[jrudge]

Seralia has the orginal AC system fitted in the mid 90s by Condaria (now part of the Dometic group).

The system works (yay) but is quite low power by modern standards.
The big issue is the fans in the cabins are very noisy and while I know I could spend £20,000 on a whole new system Id rather not.

The system is a split (is that the right term) system which has the following components:

In the engine bay there is the compressor unit which has the raw water inlet and the heat exchangers to heat/cool the circulated water.
In each cabin there is an air handler to which runs the refrigerated water (not coolant, deffo water).

The system isn't smart. The compressor unit is either on or its off, and it just keep the circulating water at a set temp (8C in summer, 25C in winter)
The air handlers in the cabins are either on or off, with two fan speeds (loud and very loud). The air handlers and the compressor bit DO NOT talk to each other.

I can run the air handlers with the compressor off an vice versa.

What I cant believe is the handlers were designed to be this noisy. What Id like to do is upgrade them to quieter more efficient units that provide more cooling. I am assuming bigger handlers might achieve this.

Last I spoke to Dometic they just wanted to sell me a £20k digital new system.

Any thoughts?

A few ideas.

There is a company ( coastal rides also ) that sell new old stock air handlers but I suspect you are playing with fire if you mix brands as they will probably expect different control signals

You coul
1 replace motors if old and noisy
2 by a fan speed controller on eBay and try one. If you slow it down the noise may reduce significantly with not much impact on cooling.

 

[BartW]

Hi jez,

I have exactly the same system in BA,

regarding the air handlers,
we clean the filters regularly, (better airflow)
and I have put a few drops of oil on the fan motor bearings, this made them significantly more silent.
but they are still more noisy then a modern system.

we have 2 compressors in the central unit, which can work in parallel for more cooling power,
but we hardly ever switch them on both, because me and my wife prefer less cooling than most brits ;-)

I'm afraid that any upgrade of any part of the system will be costly,
there is a lot of preparation and labour involved, for just replacing the air handlers...

 

[Mr Googler]

My old condaria system had thermostats in each cabin...this would turn the fans on or off....should be easy to fit to the fan power supply.

My fans had 3 speed settings which again should be doable.

This was all put in 1988 and wasn’t noisy at all.

http://www.midshipboats.co.uk/

Have a chat with Edd.....bit of a condaria / dometic guru

 

[BartW]

My old condaria system had thermostats in each cabin...this would turn the fans on or off....should be easy to fit to the fan power supply.

same on mine, its just a basic themostat with a on / off contact, in series with the fan min/max/off switch

 

[petem]

A few ideas.

There is a company ( coastal rides also ) that sell new old stock air handlers but I suspect you are playing with fire if you mix brands as they will probably expect different control signals

You coul
1 replace motors if old and noisy
2 by a fan speed controller on eBay and try one. If you slow it down the noise may reduce significantly with not much impact on cooling.

J, what control signals are you talking about? Jez said that the compressor and handlers aren't linked.

Instinctively, new fan motors feels like the way to go. I wonder how generic they are?

 

[Portofino]

Silent airco is out there boys .

You have all probably heard me witter on before about this topic = silent airco .
Mine being a hotel day boat based in Capri was not originally specced with airco .
I took that as an advantage, it would have had some system similar to Jez and Barts or worse self contained units .
The previous boat had noisy ac , it was difficult to sleep .

I did a fair bit of research , spoke to various people and the local S/Skr chaps put me in touch with a Italian guy who works the CdA replacing noisy airco , surprisingly on new boats for the same reason noise .
He’s doing a roaring trade ripping out noisy airco , it’s a very common problem .

Frigomar

That’s the brand . google + u tube for details

There’s a added technical advantage over its super silence it’s very low power consumption. Lack of start spikes + much more .
The main chiller ( there smallest ) is 42,000 btu and it lives under a bunk in the rear cabin .Any occupants can’t tell it’s running .

They do separate air handlers all sizes n shapes ck out the website .
The whole system is “ smart “ but if you ask I guess they could supply compatible switched air handlers for your engine room 1/2 .
So buy the Frigomar silent air handlers first and mate them to the chiller .

Beauty of Frigomar is you run it on an inverter ( low power consumption remember) which I do while running the engines .
So by the time you arrive at port from a day out the boats ice chilled below = Nice .
Then I just switch to shore power - easy .
It’s stays on until we leave next morning. You just don’t hear a thing .:encouragement:

Advice is free .

 

[MapisM]

Last I spoke to Dometic they just wanted to sell me a £20k digital new system.

Why am I not surprised? Try to speak to Ferretti, and they will want to sell you a million+ new boat...

First things first, J: can you check the exact model of your chiller unit (the one in the e/r)?
Chances are that it's called "PCWM/FCL", but what really matters is the number that should follow (either 4500, 6000, 7500 or 9000, I guess).
On that basis, we can understand whether the system really is "low power" as you say, or it isn't working as it should.

Next, fancoils: obviously, they are as critical as the chiller to the overall effectiveness of the system, but unless you can see any leaks around them (beware: a bit of condensation is normal, and shouldn't be confused with leakages), the only problem they might have is a clogged filter.
When I bought my boat, a replacement of all filters was all it took to enhance the system efficiency dramatically.
Their noise does depend on the fancoil motors of course, but not only.
Placement and the material surrounding them also matter. A lot.
On a Ferretti 57, whose interiors are mostly made of grp liners (as opposed to wood in mine), I heard the very same Condaria system which I have in my boat running in the cabins, and the noise difference was like night and day.
I can't remember if they already used grp moulds for the interiors, when your boat was built.
But if they did, even new fancoils might not improve noise as much as you would like, I'm afraid.

As an aside, why do you think that the chiller and the fancoils not "talking to each other" is a problem, in practice?
The chiller must keep the circulating cooling liquid (btw, there should actually be some glycol mixed with water, but this is marginal) at the preset temperature, and the fancoils are driven by each thermostat. What else would you want them to do?

 

[markc]

Hi have a Condaria system too. The air handlers have a 3 speed fan and a thermostat and they are only noisy if on full whack, so maybe a little oil in the bearings as BartW suggest? Also is the water pressure in the chilled water part high enough because I had a leak and the pressure was low = rubbish cooling.

 

[MapisM]

Apropos of AC update, I hope WL doesn't mind if I use this thread rather than opening a new one for a rather peculiar, but still AC-related, small problem that I've got with my system.
Btw, chances are that the components I am going to mention were fitted also in Seralia.

In each cabin, I've got these very simple thermostats.
In spite of their age and old school technology, they still work well.
With the exception of one (in main cabin, as it happens) which doesn't react as promptly as the others to temperature changes.
I mean, with other thermostats, after they switch the respective fancoil off (when the preset temp is reached), they turn it on again as soon as they sense a small temperature difference, half degree or so. So, the cabin temp remains very stable and comfortable.
With the main cabin thermostat instead, it takes about a couple of degrees before it turns the fancoil back on, and that is a bit annoying.

Bottom line, I should replace the thermostat, which is no big deal since it's still available.
But while looking at it, I came across this slightly more modern model, which includes an adjustable differential between 0.2 and 2 degrees, that sounds nice.

BUT, I stumbled on a spec difference which is puzzling me.
For my old thermostat, the webpage I previously linked specifies:
"1 potential-free changeover contact output: 10(2)A / 250V"
While the newer one shows:
"1 potential-free changeover contact output: 5(3)A / 250V"

Now, WTF does the difference which I highlighted in bold mean?
Thanks in advance!

 

[markc]

Sorry, I can't answer your question P, but if you end up buying them, maybe I can join to make a bigger order as I would like to replace mine at some point (5 or 6 I think)

 

[Whitelighter]

same on mine, its just a basic themostat with a on / off contact, in series with the fan min/max/off switch

Thats also the same in mine - grey boxes with a thermostsat. I didnt mention that because I figured it wasnt important

 

[MapisM]

Sorry, I can't answer your question P, but if you end up buying them, maybe I can join to make a bigger order as I would like to replace mine at some point (5 or 6 I think)

I wouldn't hold my breath on quantity discounts, but I'll keep in touch before placing an order, M.

Btw, since you mentioned that your air handlers have 3 speed fans, that is also true of my boat, but I found that just by coincidence, looking at the label on one of them while replacing the filter.
I wasn't aware of it because the builder conveniently placed the fan speed switch near the bed, and used a plain vanilla single pole double throw switch (of the same series of lights switches), connecting the two positions to the lower and higher speed, hence leaving the mid speed unavailable.
I didn't bother fiddling with these connections to gain control also of mid speed, also because the lower speed is more than enough in all cabins, but I'm saying this just in case BartW, WL or anyone else is interested: chances are that also their fancoils are 3 speed, but with just 2 actually connected.

 

[jrudge]

J, what control signals are you talking about? Jez said that the compressor and handlers aren't linked.

Instinctively, new fan motors feels like the way to go. I wonder how generic they are?

I know there are currently none. However if you put a domestic init in for example it is expecting control signals for things like reverse cycle etc so without them I am not sure what would happen

 

[markc]

I know there are currently none. However if you put a domestic init in for example it is expecting control signals for things like reverse cycle etc so without them I am not sure what would happen

On my system, which I suspect is very similar, the change from heating to cooling is done on the compressor, not on the individual control units. The only local control is the fan speed, the thermostat and if you are reading warming or cooling from the thermostat (just reverses when the fan comes on and off), apart from that, chilled or heated water runs round the system independently

 

[Whitelighter]

On my system, which I suspect is very similar, the change from heating to cooling is done on the compressor, not on the individual control units. The only local control is the fan speed, the thermostat and if you are reading warming or cooling from the thermostat (just reverses when the fan comes on and off), apart from that, chilled or heated water runs round the system independently

Yep. this. Big rotary knob you move from summer (cold) to winter (warm). Its soo simple (which I like BTW mapis) I cant beleive you cant just add new water AH?

 

[Whitelighter]

@markC

How do you find the noise of the compressor unit. Ours is loud enough that you hear it cutting in at night. Id often wondered if you could put a sound box over it

 

[markc]

Hey Jez, tbh I can't hear it at all. I actually think it may have been replaced as genny, passarelle, watermaker were all replaced in recent years. I'll try and find a pic for reference

 

[superheat6k]

Not uncommon on many many buildings that the water chiller (your compressor unit in the ER) simply circulates chilled water and has no influence on how the child water is used. To reduce energy use increase the set point when the temperature is cooler and lower it when the temperature is higher.

For the fans see if you can find an EC Fan equivalent. Without knowing what fan you have this could be difficult. I am unloading likely to be much direct help as the EC fans we use are typically 800 or 900 mm diameter.

If you can get me the fan details I will see if I can find something - likely a scroll fan (like a hamster wheel) so need to know its length diameter and how many ribs it has, plus any details from the motor itself.

 

[MapisM]

Blimey, you can hear the chiller in the e/r from the bow cabin?!
Mine is inside a technical area aft of the e/r, just under the cockpit bench, and I can barely hear it while sitting there...
If your chiller has a digital panel, try this trick:
switch it off (from that panel, not by cutting power from its thermal switch), and then keep pressed the C button, till the display shows a rolling number.
That is the number of working hours cumulated by the compressor, and gives you a good idea of how much worn out it is.