Dehumidifier running

[NewhouseOldhouse]

Hi All

I have a 25 ltr low energy dehumidifier which I run 5 hrs from midnight to 5 in the morning.

It is in a central location of a 5 bed bungalow and still get a bit of condensation on some of the windows.

In people experience whats the best way to run a dehumidifier? The max wattage is 320W of my dehumidifier.

Thanks

 

[Harry Bloomfield]

It is in a central location of a 5 bed bungalow and still get a bit of condensation on some of the windows.

A small amount collecting at the bottom of windows is to be expected, in cooler, wetter weather. Windows are usually the coldest place in a room, so that's where it condenses.

In people experience whats the best way to run a dehumidifier? The max wattage is 320W of my dehumidifier.

Run it on a humidity sensor/switch. Have you checked to level of indoor humidity? Have you a mold, or humidity problem.

 

[Old Salt]

Run it during the day when its warmer

 

[NewhouseOldhouse]

A small amount collecting at the bottom of windows is to be expected, in cooler, wetter weather. Windows are usually the coldest place in a room, so that's where it condenses.

Run it on a humidity sensor/switch. Have you checked to level of indoor humidity? Have you a mold, or humidity problem.

Probably only replacing the glass with the k glass with warm edge bar will resolve this.

Not really just bit of condensation, althought when I turn the dehumidifier on readings can be 90% but very quickly goes back down to 50%.

What percentage is recommended the house to be at?

 

[NewhouseOldhouse]

Run it during the day when its warmer

Will try this

 

[Harry Bloomfield]

What percentage is recommended the house to be at?

IMHO 70 is just about OK, below 55 is desired.

 

[Jon c]

If you're getting bad condensation and humidity issues a longer term solution is putting in a PIV (positive input ventilation) unit. These normally sit in a loft where they draw air from the space, filter it and blow a constant stream of air into the house. The idea is this creates positive pressure inside the house so forces any humid air outside through gaps in windows doors etc.

This page provides more info https://www.google.com/url?sa=t&sou...8QFnoECBwQAQ&usg=AOvVaw3WaaGaDOP99NOvjJAlte4o

Based on personal experience I can highly recommend PIV units, have put them in a few rental properties with condensation/humidity issues and they typically resolve the problem or at least help massively.

 

[ericmark]

Why is the home damp? Cure is to stop the water ingress to start with. This house sits at around 40 - 60% depending on time of year and weather.

Years ago parents house was single glazed with metal frames with catching trays at the bottom and small holes leading outside, so the windows became dehumadity units, the fires used air from the room, and vents in the wall allowed air back in, keeping the rooms dry.

Over the years fires have been sealed up, vents blocked, and double glazed windows in plastic frames fitted, later versions of double glazing included vents in the windows, but there is a balance ventilation and heating, the best option is a heat recovery unit, but these need installing.

In the main the bath room and kitchen allows mosture into the home, extractor fans in the bathroom and kitchen can help, but also reducing moisture getting into the home.

Gas cooking can put loads of mosture into the home, with gas cooker hoods vented outside, electric cooking produces much less mosture.

But also damp course failure, leaks in roofs, even faulty gutters can cause damp, in my last house the glass fibre in the roof space was by capillary action moving the water leaked through the roof tiles into the fibre glass filled cavity in the walls so walls always damp.

At the time we had no idea what was going on. No amount of running a dehumidifier will help.

However also homes which have been re-plastered can be damp, that is clearly temporary and a dehumidifier will help.

So why is your home damp? Clearly we exhale mosture so over crowding can cause it, including any animals (pets).

 

[Jon c]

Why is the home damp? Cure is to stop the water ingress to start with. This house sits at around 40 - 60% depending on time of year and weather.

Years ago parents house was single glazed with metal frames with catching trays at the bottom and small holes leading outside, so the windows became dehumadity units, the fires used air from the room, and vents in the wall allowed air back in, keeping the rooms dry.

Over the years fires have been sealed up, vents blocked, and double glazed windows in plastic frames fitted, later versions of double glazing included vents in the windows, but there is a balance ventilation and heating, the best option is a heat recovery unit, but these need installing.

In the main the bath room and kitchen allows mosture into the home, extractor fans in the bathroom and kitchen can help, but also reducing moisture getting into the home.

Gas cooking can put loads of mosture into the home, with gas cooker hoods vented outside, electric cooking produces much less mosture.

But also damp course failure, leaks in roofs, even faulty gutters can cause damp, in my last house the glass fibre in the roof space was by capillary action moving the water leaked through the roof tiles into the fibre glass filled cavity in the walls so walls always damp.

At the time we had no idea what was going on. No amount of running a dehumidifier will help.

However also homes which have been re-plastered can be damp, that is clearly temporary and a dehumidifier will help.

So why is your home damp? Clearly we exhale mosture so over crowding can cause it, including any animals (pets).

As you mention yourself a lot of the time damp/humidity only comes from peoples daily activities, cooking, showering, drying clothes etc. If a property has rooms on the smaller side and poor or no ventilation, this will build up very quickly, so the only real solution is to create ventilation. Passive ventilation ie. window trickle vents usually isn't enough, so either more powerful or constantly running extractor fans are needed, however that only really applies for bathrooms and kitchens.

So to look after bedrooms and other rooms that don't typically have extractor fans, a PIV unit or other types of whole house ventilation are a good solution. I'm not sure why some houses seem to be more prone to condensation than others, I have known a few rentals where there's been no damp issues with one tenant living there but the next tenant has lots of condensation issues, so I think it's often down to people's behaviour.

 

[ericmark]

I have to agree with @Jon c I could not to start with understand why one house had mould in the bath room, and another two did not, what I realised was the shower enclosure was acting as a chimney circulating mosture through out the room, the homes without the problem one has shower doors sealed at bottom so no circulation, the other a wet room so no shower enclosure so again no circulation.