PIV system location

[pledmonds]

Hi there

I'm planning to install a PIV system, but since we have a loft conversion, installation on a landing is not physically possible (the loft conversion is over the first floor landing, and access above the second floor landing virtually impossible (and the landing itself is less than 1m2 and already hosts a smoke detector.

As a result, I'm considering installation in a first floor bathroom, just off the main landing.

I appreciate that installation in a bathroom is suboptimal, but I've not been able to find any guidance as to whether a PIV system would still be effective (and if so, how much less effective it might be than if sited optimally).

For context, the bathroom has a separate in-line extractor fan venting through the ceiling externally through the roof, and the bathroom door is kept open (with access direct to the central landing off of which all first floor rooms lead) except when in use.

The only other possible location would be in another room just off of (and at all times open to) the first floor landing (a home office which is effectively a landing area at the bottom of the stairs to the second floor), but it would need to be sited close to a wall, which would of course affect dispersal.

Any advice?

Phil

 

[EFLImpudence]

I'm planning to install a PIV system,

Why?

 

[pcaouolte]

You might be better off with a wall mounted PIV if you can install that in a position where it introduces air onto the landing:
https://www.nuaire.co.uk/residentia...flatmaster-positive-input-ventilation-systems

In you bathroom the air introduced by the PIV may well go straight out of the bathroom extractor ducting without affecting the rest of the rooms in the property.

 

[pledmonds]

Why?

We have condensation issues (110 year old house, solid brick walls, modern life); they seem pretty highly recommended as an element of the solution to that and are a huge amount cheaper than the 'hack off all the plaster and lime plaster everything' shouts that usually come up.

Do I infer from your question that you don't recommend PIV?

 

[pcaouolte]

I, from my own experience, do recommend PIV as a method of reducing condensation. This assumes that you have already tried all of the "free" methods of reducing the water content of your home; not drying washing indoors, using the bathroom extractor, using a kitchen extractor if fitted, covering pans when cooking, opening windows to allow air exchange for a short time every day.

 

[EFLImpudence]

Do I infer from your question that you don't recommend PIV?

I don't really know much about it per se.

I just wonder what is the advantage of blowing in air rather than sucking out the actual moist air.

Much more important for reducing condensation, of which I have lots of experience from managing flats, is what pcaouolte says above.

 

[pcaouolte]

I just wonder what is the advantage of blowing in air rather than sucking out the actual moist air.

You can do both. The incoming air from a PIV is filtered so it doesn't bring in as much dust as opening a window. You leave them running permanently so you can gently introduce air when you are away from home and wouldn't want the windows open. The speeds are variable so you can set them according to the size of the property. The disadvantage is that they create a cold flow of air near the outlet which some people dislike, you only feel this cold air in the immediate area of the PIV outlet, it doesn't create a draughty feel in other rooms (this is another reason for not having the outlet in a bathroom, who wants cold air blowing on them in the bath?).

The OP may have a three storey property which may limit the PIV which they can install or require a special outlet, this should be investigated before making a purchase. Nuaire support are usually very helpful.

 

[pledmonds]

In you bathroom the air introduced by the PIV may well go straight out of the bathroom extractor ducting without affecting the rest of the rooms in the property.

Yes that was my thought about the bathroom installation. I suppose I was wondering whether anyone else had installed in a bathroom to gauge whether it's a 90% loss or a 10% loss, or somewhere between the two.

You might be better off with a wall mounted PIV if you can install that in a position where it introduces air onto the landing:
https://www.nuaire.co.uk/residentia...flatmaster-positive-input-ventilation-systems

I don't think there's a routing in our layout that would work (at least, not without some ugly boxing in) for a wall-mounted system, thanks though

 

[pcaouolte]

No I haven't installed one in a bathroom and I would not. I would expect that (almost) all of the air would go straight out of the extractor ducting, the air will take the route of least resistance. I also wouldn't want to be sitting in the bath with a steady stream of cold air from a PIV blowing over me. If you email Nuaire they may be able to suggest the best solution for your circumstances, plans of your home would help them.

 

[pledmonds]

No I haven't installed one in a bathroom and I would not. I would expect that (almost) all of the air would go straight out of the extractor ducting, the air will take the route of least resistance. I also wouldn't want to be sitting in the bath with a steady stream of cold air from a PIV blowing over me. If you email Nuaire they may be able to suggest the best solution for your circumstances, plans of your home would help them.

Thanks. Not so worried about a draughty bath - we never use the bath (and anything that gets the kids to bath quicker is good with me!), and would probably get a heated unit anyway.

I suppose we could also get a good non-return valve for the extractor which - provided it would form a decent enough seal - would help to mitigate the push/pull wastage (besides when the extractor is actually on - but we're talking about a fairly small % of the time).

I have emailed Nuaire as you suggested - will see what they suggest.

 

[pcaouolte]

Bear in mind that the heaters in the heated units just take the coldest edge off the air, they definitely don't provide warm air. I have a heated unit at home, I have to look at the energy monitoring that I have connected to it to find out if the heater is on or not.