Diamond Core Drilling

[budest]

Hu guys,

I want to vent a portable air con unit out through a cavity wall. The flexi hose from the AC is just under 6" in diameter. I am therefore assuming a 6" core bit is required? What about going through the wall, would I require a pipe to extend out to the vent?

Thanks in advance for any tips.

 

[opps]

I would recommend buying a long drill bit that is the same diameter as the center pin in the core arbour. As you drill from the inside out, you will get a small breakout in the outer brick/render.

Drill the majority from the inside. Finish the last inch or so from the outside.

Is the wall a solid 9" wall or a cavity wall?

There a number of through wall fixing kits. eg

Airvent 100mm Internal Fit Wall Kit

Quick and easy install. Extendable length (225 to 390mm) can be fully installed from inside the property.

www.toolstation.com

I don't have much experience of using them, so hopefully someone more knowledgeable will be along soon.

 

[DAZB]

I would go with a 4 inch core and get a 6" to 4" reducer (see the link for an example), that way it is simpler to slide a short section of soil pipe through the wall and add a vent to the external wall.

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[johnny2007]

I would go with a 4 inch core and get a 6" to 4" reducer (see the link for an example), that way it is simpler to slide a short section of soil pipe through the wall and add a vent to the external wall.

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I wouldn't do that unless the manufacturer's installation instructions approve it.
To core drill a 6", you'll need a coring drill with clutch.
Mark the centre and drill though with a long drill bit so to go through the wall.
Whether it's a cavity wall or not, the harbour will have a pilot bit which sticks out an inch or so further than the core bit.
Start from where you would not mind having more mess (outside usually).
Measure the wall thickness and put a piece of tape an inch or so shorter so you don't go through.
Once you reach that mark, core from the other side.
Keep a very light pressure and let the machine do its work.
If the clutch starts engaging too often, take a break, some walls are harder than others and arms get tired, so they don't hold the drill straight.

 

[budest]

I wouldn't do that unless the manufacturer's installation instructions approve it.
To core drill a 6", you'll need a coring drill with clutch.
Mark the centre and drill though with a long drill bit so to go through the wall.
Whether it's a cavity wall or not, the harbour will have a pilot bit which sticks out an inch or so further than the core bit.
Start from where you would not mind having more mess (outside usually).
Measure the wall thickness and put a piece of tape an inch or so shorter so you don't go through.
Once you reach that mark, core from the other side.
Keep a very light pressure and let the machine do its work.
If the clutch starts engaging too often, take a break, some walls are harder than others and arms get tired, so they don't hold the drill straight.

Thanks for the info. What would I then connect the a/c flexi hose to to go through the wall? I have seen them taped to a piece of pipe.

 

[Madrab]

What make/model of AC is it?

 

[johnny2007]

Thanks for the info. What would I then connect the a/c flexi hose to to go through the wall? I have seen them taped to a piece of pipe.

Check tg he manufacturer instructions.
It is possible you can pass the flexi straight through the wall without sleeving it, or it needs a rigid piece of pipe which is readily available, but you need to check the instructions.
Give us the model number so we can check online.

 

[JohnD]

I've only used a hand-held myself, they are very heavy and you need a firm place to stand especially if working at shoulder height.

In Switzerland I have seen them with a supporting frame you bolt to the wall (and a water hose). Can you hire them here?

Tilt it slightly so any rain or condensation runs outwards.

A cavity wall needs a sleeve to keep the cavity clean. Pack it with loft insulation first. I find the flexible hose will push into plastic pipe even if they are nominally the same size. The flexi is not very durable.

 

[Madrab]

In Switzerland I have seen them with a supporting frame you bolt to the wall (and a water hose). Can you hire them here?

You can, diamond corers and driller use them all the time - it's called a core drilling mast - some are floor standing but others are on full frames to bolt to the wall. It is quite an undertaking though as you need to drill and fit resin anchors to take the weight of the drill, mast and tube etc. Not usually DIY territory.

A normal good quality SDS drill (clutched) with a good quality diamond dry tube should do fine. Use a good solid A frame ladder end on with a body or 2 to support/foot it should be fine. Hard part is starting the core, once it's started then the ladder can support the gun whilst the hole will support the tube.

 

[budest]

What make/model of AC is it?

Hi mate,

It's a "Meaco MeacoCool MC Series 8,000R".

 

[budest]

Check tg he manufacturer instructions.
It is possible you can pass the flexi straight through the wall without sleeving it, or it needs a rigid piece of pipe which is readily available, but you need to check the instructions.
Give us the model number so we can check online.

Hi there, thanks for the reply.

Here is the unit.

 

[budest]

I 'm thinking about something like this? Thing is it's 160mm in diameter which is almost half an inch larger than the hose. So how would it fit?

Manthorpe Core Vent Brown 160.5mm x 350mm - Screwfix

Order online at Screwfix.com. 127mm (5"). For ventilating gas appliances and general through-wall ventilation. Max. 100cm² airflow. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

 

[JohnD]

I 'm thinking about something like this? Thing is it's 160mm in diameter which is almost half an inch larger than the hose. So how would it fit?

Manthorpe Core Vent Brown 160.5mm x 350mm - Screwfix

Order online at Screwfix.com. 127mm (5"). For ventilating gas appliances and general through-wall ventilation. Max. 100cm² airflow. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

It also says "127mm (5")"

Maybe one is the bore and one is the size of the outer hood.

cowl vents are widely available

Cowl Vents | Ventilation | Screwfix

Buy Cowl Vents at Screwfix.com. A hooded vent. Prevents drafts. Suitable for flat or round ducting. Click and collect in hundreds of stores nationwide.

www.screwfix.com

But there are some 125mm cooker hoods.

You are usually better off using full bore, not reducing the size

I think you need to look at a ventilation supplier rather than screwfix.

What size do you actually need? There are some 150mm round on here, and they have other sizes

6 Inch Flexible and Rigid Ducting Clips - Ventilation