Code 1 Install By National Ventilation Company

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

sparkytim

Well-known member
Joined
Mar 14, 2010
Messages
1,809
Reaction score
1
Made an interesting discovery in a loft yesterday. Recent VERY EXPENSIVE loft mounted fan installation pushing loft air into the property, sold to the client as solution to a massive damp problem by a national Environmental Ventilation company (clue to who in there).

I had just shot up ahead of the BG loft insulation guys to get a smoke alarm 3183Y link in before the dreaded fibreglass went down, nearly stuck my fingers into an exposed choc block laying nicely just inside the loft hatch!. 

Managed to get down and pull the 5 amp 3036 before the boys went up preventing any fatality.

After they had gone got up to investigate and followed a nice shiny 1.5 T&E from the booby trap to an un-switched 3 amp fused connection unit, supply point for the Positive Ventilation Unit.

Well now very helpfully they had emblazoned on the unit contact information for the company which I duly made use of to have a chat.

"Was it there normal installation practice leave behind a Code 1 condition (Exposed Live Conductors) ?"

Most certainly NOT was the reply, armed with the property details they promised to get back to me within the Hour. True to their word I had a call from their QS to inform me that this had been installed by a Franchisee and they would contact him to return and rectify.

I informed the incensed client who had just spent an absolute fortune on remedial work to the property re plastering and installing air bricks along with bathroom extractor, all supposedly not required according to the Environmental experts.

A while later gets a call from the installer, "I am NOT a cowboy" he protests "I am registered with NAPIT",  "Thanks for that info" I reply " I will send them the Photos, perhaps you can use this job for your next assessment ! "

He turns up a couple of Hours later in a bit of a fluster, takes a look and admits he must have had a bad day, takes a Junction box up and sorts it.

"Minor works for the job?" I ask " Well no not this one"  I give him what for and he crawls away tail between his legs back to find his horse.

Its people like this giving us a bad name leaving behind potentially lethal installs.

It was good to be able to look one in the face and tell him just what he needed to know.

I hope he will learn from it.

 
Quite apart from the dodgy electrics.

I take it this is a condensation issue in the loft. So how to they expect to solve it by pumping damp loft air into the house?  It will cool the house in winter and overheat the house in summer. Most bizare idea I have heard for a long time.

By all means ventilate the loft if needed to the outside, even if that involves a fan, but to ventilate it into the house just does not make sense at all 

 
its to prevent condensation inside the house, not in the loft. but yes. it will cool the house in winter and warm it in summer, although they do switch off when it gets too hot

 
I've seen systems like this before in really damp houses,,, they call it positive pressure... I think they recon that if the pressure is greater inside the house than outside that it won't allow damp to enter

 
Damp doesn't normally "enter" a house, it's created within by people breathing, cooking, washing etc.

Older houses can be prone to damp walls just by the nature of the construction, I'm thinking old houses with solid, non cavity walls.

All that positive pressure can do is is increase the number of air changes per hour by forcing more air to exit through whatever ventilation is there already.

From my experience as a landlord, most of the times we have had damp issues have been a lifestyle problem. Things like the tenant turning off the bathroom fan because it's too noisy (don't have fan isolators any more in my rented property) or hanging loads of soaking wet clothes inside the house to dry, but not opening a window or anything to let the damp air out.

 
it is pointless having a +ve air pressure fan and an extractor fan running at the same time

 
Wrong Nicky, it depends on the airflow of the two, one can maintain positive, negative or neutral air pressure with input & output fans.

 
calculations would have to be made im sure but like leaving a window open would require massive +ve pressure for the fan to be effective

 
I do quite a few of these 'posi flow' systems as they have been called, and in all truth I find they seem to work,

I cant actually think of one single case where I have been called back to for the problem persisting.

maybe not purely for the fan, but it obviously assists,

recently I have fitted one for a privately owned house of a very clued up guy, if it didnt work I would be back with an earful of whatever.........

 
POSITIVE VENT FAN CONNECTION.JPGPictures did not turn out to well but here it is a quality install connection if I have ever seen one!.

 
It LOOKS like a BS chocolate block but could someone

explain why a loft needs any ventilation when proper

construction methods would ensure that this would be

achieved by natural means?

I had a kitchen window mounted fan in my last house;

No smells, no dust or greasy debris on my kitchen library.

The ones who bought it had new windows and removed

the fan.

 
It LOOKS like a BS chocolate block but could someone

explain why a loft needs any ventilation when proper

construction methods would ensure that this would be

achieved by natural means?

I had a kitchen window mounted fan in my last house;

No smells, no dust or greasy debris on my kitchen library.

The ones who bought it had new windows and removed

the fan.
its not to ventilate the loft...

 
Top