New Oil fired boiler choice

[Quillan]

Whatever make they have in at the time. In truth the insides are all the same, the most important thing is the pump that pushes the refrigerant round which some name on the box it all comes in (well box's actually, there two pieces, one for inside and the other for outside) and you want a 'branded' pump like Hitachi, Panasonic, Toshiba or whatever. As you know anything that rotates or moves is pron to failure so a quality pump is important. They all have 2 year warranty and we have just found out that for 4.85 Euros a month AXA will insure them against breakdown after the warranty period and up to 10 per house, or so it says on the paperwork. I suspect other companies offer similar deals. Get the pre gassed pipes, their 4M long and cost around 90 Euros per set (two per set) and either make brackets for outside or by a kit for around 25 Euros. Apart from the hire of a core bit that's about all it costs. Oh yes the thing is powered from the unit inside the house for which you get about 1M of cable with a normal 3 pin plug on the end. I do not have a clue if they should be on a separate circuit (like washing machines etc) but I have simply used the outlets that were there for the heater and put a normal 3 pin socket in place of the junction box. As it draws a lot less current I can't see that being a problem.

[woolybanana]

Quillan, what is the approximate weight of the wall units? I need to make provision to attach them and can do it now as I am building the wall, (as well as laying the electrics for when they are needed).

As the downstairs hall of my house is cold, the walls are now largely insulated and the door is being covered with a thick, removable curtain, but I wanna heat that area with an air/air system and permit the hot air to penetrate upwards through the stairwell too.

[Quillan]

Well I don't know to be honest but perhaps I can put it this way, I can carry the outside unit for about 10M (I am not exactly a power lifter) but I could not lift it in to position on my own, I had to get help. Personally I would use the brackets they sell because there are certain distances that need to taken in to account when positioning them, mainly from the wall to the back of the unit. They also have big rubber feet to stop vibration and it was a bit fiddly getting the bolts through so you need somebody to help you position it on the bracket although it's not that difficult.

The indoor bit is very light and you wont have any real difficulty positioning it although you should pay attention to where the hole through the wall is in conjunction to where the mounting frame is positioned. You won't need help with this.

There are two DVD's that come in the box's, in French of course, and you do need to watch them as the written instruction are pretty naff. One comes with the a/c unit and the other with the pipes.

I found the following set of instructions which give distances etc and are much the same as you get with the units from Brico Depot although the pipe is slightly different because it has different connectors as its already filled with gas. http://www.aircondiy.com/installation_guide.shtml but everything else is much the same.

Don't mount the outside unit where there is direct sunlight and have some form of canopy over it to protect it from rain and sun.

The indoor unit has an 'osilating' mode which swings the air directing vanes from left to right and also up and down. It can't direct the air upwards, the maximum angle is straight out.

[Chancer]

I second all that Q has said but question the bit about not mounting them facing the sun and constructing a shelter.

Mine is facing plein sud, not that the suns shines here except out of my ****, and exposed to the elements, I have never in my life seen an outside unit under a canopy, most of them are on rooftops.

Core drill = une carroteuse, core bit = une carrotte.

I liked your logic about saving money because they replace heaters that cost more originally, sounds like une femme entretenu seeking reassurance during retail therapy!!  

[Quillan]

Well you can put it anywhere you like but because of the way these things work, there are suggested positions, mainly East or West facing. The reason I believe (not being an expert) is that in summer for instance you are creating cold air inside and hot air outside. Thermal transfer is better outside if the ambient air temp is as low as possible. Having direct sunlight on the external heat exchanger can increase the temperature by two or three fold (especially as the filter is black) so the best place to have it would be North facing. The same can be said the other way round, if your using it to heat a room then ideally you want it South facing. In an ideal world I suppose it would be handy of you could move it for summer and winter but you can't. Of course it won't stop working but it just won't be quite so efficient particularly if you have an inverter type or so I have read. Many people don't have a choice, if you visit Perpignan or Narbonne people have apartments mainly with south facing terraces, great for sunbathing but the lounge normally heats up so they stuff a/c in and the obvious place to put the outside unit is on the terrace wall.

Putting some form of cover over the unit, providing it does not obstruct the airflow, does protect it from the elements, mainly rain. This can increase the lifespan of the unit but again not really necessary. Some people put them in some kind of box to hide them because they think them ugly, that's OK providing again you don't block the airflow. Personally I am lucky because I have a terrace outside the lounge and the house roof extends over the terrace so I have placed the units under that bit of the roof which protects them from rain and direct sunlight even though the terrace faces south. Two of the bedroom also face south so I had no alternative but to mount them on the outside wall facing south and with no protection. These units however are not inverter types but that's down to the amount of usage they get, given that they are on timers and the guests only have them on for short periods of time the cost of putting inverter units in these rooms against the savings gained is very small.

Just for Wooly I thought I might add what the difference is between the two type of units in simplistic terms. The normal, non inverter units, switch on and off as the temperature changes in the room. An inverter unit does not, it can increase or decrease the speed of the pump and fans. Switching on and off burns more electricity than simply varying the speed which is why none inverter units have a 'B' rating and inverter units have a 'A' rating.

[woolybanana]

[quote user="Théière"]

Who doesen't so Insulate, Insulate, Insulate, swap single glazing for double or triple. Insulate all rooms where possible. Why do they still sell placo with expanded foam on the back when extruded is so much better and doesn't turn into millions of little balls as it breaks down.

[/quote]

Théière what do you mean about the difference between placo with foam on the back and extruded? Is the latter merely the big sheets of stuff one can buy and it is better than rockwool?

Is the plastic sheet with what looks like aluminium and foam bubbles any better?

[Théière]

Hi Wooly, I see placo (doublage) with expanded polystyrene all the way up to 120mm thick but expanded is not as good an insulator as extruded polystyrene and I have only seen placo bonded to 30mm (from memory) extruded polystyrene.

It is better than rockwool as it doesn't absorb moisture in the same way an you only need around half the thickness of extruded compared to rockwool.

The bubble based foil doesn't seem to last that long so a different multifoil construction is better and recently we noticed there was only one on sale that carried a 10 year guarantee, so that's what we bought. Noticed improvement immediately it was installed.  

[woolybanana]

Thank you T, I shall try and find out about extruded later this week.

I am told the bubble based stuff has to have a 2 cm air gap either side to be effective. Did you install it that way? And that it is not recognized as an official insulation material if you need a thermal check?