PDA

View Full Version : Extending Pipe Work



rob75
01-07-2010, 06:48 PM
Hello Everyone!

Please be gentle, this is my first post and I new to air conditioning.

I just purchased an interior and exterior unit from a well known UK DIY superstore. The unit is for use in a property in Spain where the internal plumbing is already prepared which runs to the roof of the property where other exterior units are mounted.

The problem I have is that the interior unit has come with 4 metres of plumbing pre-fitted. The 4m run is no where near long enough if I want to use the existing plumbing that is preferable.

One option I have is to mount the exterior unit on the other side of the interior unit and use the 4m supplied but this will mean a messier job and the units being mounted in less than desirable locations.

So my question is can I cut and extended the supplied pipe work on the unit. Like I said I don't know very much about this, I'm not even sure if what I want to do is possible let alone advisable.

Any advice would be very much appreciated. I can supply more info and or images if required.

I'm determined not to be beaten by this.

Many thanks in advance,

Rob.

james10
01-07-2010, 07:25 PM
The unit you have bought is a diy unit if you need longer than the 4m pipe run you need to get an air conditioning engineer in to fit a proper ac unit the "pluming" is not just as simple as joining th pipes together you need specialist equipment ther are also various other factors to take into consideration

frank
01-07-2010, 09:01 PM
Excellent point.
With Air Conditioning, the pipework is not 'Plumbing' and dangerous pressures exist in the pipework.
The best advice would be to get a qualified tech in to fit your unit and then you can sit back and enjoy the product knowing it is both safe and fitted correctly.

monkey spanners
01-07-2010, 09:08 PM
You will need to go on a training course to get qualified to work on anything containing refrigerant in europe...

If your unit has quick couple style pipework they need removing, they will leak after a while. If you are extending the pipework you will need to find out the maximum lenght the unit can cope with, possible ten meters on a small split system, you will need to find out the max lift it can cope with, possibly five meters, and the aditional charge per meter over the length of the supplied pipework. Is the pipework in spain the correct size for your unit?

In short yes it could be possible but depends on the max run and lift requirements of your unit, and would need fitted buy a certified installer much the same as you are not allowed to work on gas central heating.

Brian_UK
01-07-2010, 10:35 PM
You might also find that the pre-supplied pipework is full of refrigerant so cannot simply be cut and extended.

Simple answer as stated above is to get a qualified refrigeration engineer to to any installation work other than your plug'n'play system. As it stands you are not allowed to do anything more than connect that unit as it stands.

rob75
21-07-2010, 12:36 AM
Thanks for the advice.

IN the end I decided to go with the pipework supplied in order to avoid any problems. The unit is no working fine!

However I have some genral question regarding the operation of the unit:

Referring to the manual, the unit has 4 modes:

Cooling Mode - self explanatory

Heating Mode - self explanatory

Dry Mode - manual says if the temperature is within 2 degrees of that set the unit opertes in dehumidifying mode only

Automode - Room temp to be automatically maintained between 20-25 degrees. When room temperature has been reached between these two temperatures the unit compressor will stop an dleave the fan running to recirculate room temperature air.

I'm just not entirely sure when to use the Dry and Auto modes. Is Auto mode a power saving option perhaps?

The remore has a fan button which can be set to 1,2,3 or auto. What is the need for a fan on an air con unit, and what is the difference between 1-3 and auto?

Apologies if these are obvious to you guys but I am new to this!

Many thanks in advance,

Rob.

Brian_UK
21-07-2010, 10:47 PM
OK Rob, here goes... :)

Dry mode will attempt to maintain the present humidity level when the mode was selected. It does it by switching the cooling on and off to remove moisture but at minimum temperature change. You live in the UK, forget DRY mode.

AUTO Mode, the system will try and maintain whatever your set point temperature is. So, on a cold day when the room temperature drops below your set point it will switch on in heating mode. When it reaches set point it will switch off again until the temperature drops again.

However, should the room temperature start to rise, first warm days of summer etc, the unit will switch over to cooling mode and reduce the room temperature down to the set point before switching off.

Things to note in Auto mode.

Say you have a set point of 21°C.

In Cooling mode when the room temperature reaches 22° the cooling will switch on, when back down to 21° it will switch off.

Likewise in Heating when the temperature drops to 20° the unit will switch on.

In Auto mode, set at 21° the air temperature needs to reach 22° before the cooling will be selected and then it will operate as before. For heating to be selected the room temperature needs to drop to 19°.


What is the need for a fan on an air con unitYou didn't mean to ask that out loud did you? :eek:

Fan selections.
1 = low speed, quieter and less airflow.
2 = medium speed, bit louder and more airflow.
3 = high speed, nosier and maximum airflow.
Auto - Unit will select the best fan speed for the conditions.

Say the room is hot and you have just turned on the unit in cooling. The fan will run at maximum speed to cool the room as fast as possible.

As the room temperature drops towards the set point the fan speed will slowed through medium to low. If at low speed the temperature starts rising then the fan speed will increase again.

paul_h
22-07-2010, 09:03 AM
Wow, those DIY splits are worse than I thought, seems they don't even come with a users manual!

I actually installed one last week, someone bought one from ebay but still wanted an installer for the electric, drilling holes through the walls.
I had the opposite problem, where to shove the extra 1.5m of piping wrapped in fluoro yellow covering? :D
Forget ever extending the piping, it would be a massive pain, not worth the hassle. Better off buying a regular unit if you needed a longer pipe run and paying for the install.

rob75
31-07-2010, 05:14 PM
Thanks for the replies guys, apologies for the time taken to reply but I don't seem to be receiving the reply notifications (even to spam/junk).

The unit did come with a manual but it is of little help. It goes along the lines of:

"Auto: press to set the unit to auto mode"

If only it had some example such as those given by Brian_UK I then wouldn't be asking here ;0

Brian - I am using the unit in Spain not the UK so perhaps the DRY mode is of some use?

So the point being - in AUTO mode it will switch between cooling and heating in order to maintain the set temp. Not a good option say in the summer when it may start working to 'heat' the room!

Apologies if the fan question sounded a little dumb. I was thinkning the fan related to the fan on the exterior unit however after reading your reply we're talking about the fan in the interior unit which throws out the cool air right? Your explanation now makes sense though now though!

Paul, had I known what I know now I may well have opted for a non-DIY unit. However I picked up this DIY kit for £99 (which I just couldn't resist) for the interior and exterior unit. The kit even came with a SDS drill piece to make the whole through the wall! I then paid £120 to get it shipped from the UK making a total of £220 which really isn't bad. It was not til I got an engineer in that I learnt what a DIY unit was and how extending pipework is a no-no.

My final question relates to the efficiency of the system. At this low price I know it is not gonig to be the most efficient system to run. Looking at the external unit I can see the following data:

Cooling Capacity 3500w
Cooling Power Input 1335w
Cooling Rated Input 1800w

What's the difference between the above and which tells me the approx running costs?

Thanks again for your help snd being patient with me!

Rob.