Mould/Damp Mildew smell... Dehumidifier ?

DubInTheWest

Hey guys, I have a problem that I'm trying to get to the bottom of and sort out.
Basically we moved into a 4 bed bungalow that was idle for about 4 years before we moved in. The house and gardens were ideal but we could smell a musty smell from the outset and there was mold in the ceiling in one of the bedrooms. This room has always been an issue. I bought some astonish mold remover and clean it but it comes back every time. There seems to be a very strong smell from the carpet in this room too.

If I'm away from home for a few days and come back the smell really hits me. Seems we are used to it when we are at home. We are renting and at a reasonable price. The landlord doesn't want to know about anything so I just look after anything and everything and it has been a lot.

So what I want to know is, how can I go about getting rid of this smell from the house ? Will a good dehumidifier do the job or at least help out big time ? Do I need to take up the carpet in this room and get new carpet ?
We don't dry clothes or anything like that in the house, our dryer is outside in a seperate room.

If a dehumidifier will do the job can you recommend me a good one in the region of €150-200 please.
I was looking at this one >>> https://***.amazon.co.uk/EcoAir-DC18-Compact-Portable-Dehumidifier/dp/B0194MCV0G/ref=cm_cr_arp_d_product_top?ie=UTF8 any use ?

Cheers

editorsean

Assuming it's not caused by a leaky pipe or roof (see this video), I reckon a dehumidifier will eliminate the mould and significantly reduce the dampness smell.

If the house is not heated while you're away, I suggest going for a desiccant dehumidifier as they can extract a lot more moisture than the more common compressor type at low temperatures. On the other hand, if your house is mainly kept above 15C, a compressor dehumidifier (such as your Amazon link) is cheaper to run.

At about 15C, a compressor model will only remove about 1/6th is rated capacity (e.g. 2 litres a day for a 12 litre model) as it will spend a significant amount of time defrosting ice build up on its evaporator coils. A desiccant model uses a desiccant wheel to adsorb moisture, so does not have any issue with frost build-up and will continue to extract close to its rated capacity down to near freezing.

kirving

Might also be worth your while renting an industrial unit at first to dry out the place, and then maintain the level with a smaller unit.

DubInTheWest

Thanks for the information guys it's pointing me in the right direction. I'm not sure what the temp would be in that room in particular. It is the coolest room in the house so it could be bordering on 15C even if the range is lit in the evening time. If the range is on during the day it will definitely be over that. I'm wondering if there is a big difference in the cost of the compressor one vs the desiccant one running for most of the day.... Maybe my best bet would be to get the desiccant one.

Do you reckon I might need an industrial unit ? The place is not soaking just a really bad smell from the carpet. I have a feeling there was a radiator leak in that room before we moved in. When we moved in, the carpet was very damp to the touch now it's dry but just smells really bad. In fact, if I say leave a jacket or cardigan outside that room and it falls on the floor, the smell is mildew is really bad from the clothes. That's why I'm really going to go hell for leather on this and try get it sorted.

Any recommendations on a desiccant dehumidifier ?

Thanks again

editorsean

At around 15C, I reckon that both desiccant and compressor based machines have about the same power consumption per litre collected, i.e. around 500ml collected per 1kWh of power consumed with the air humidity about 60% RH. The extraction rate increases as the temperature rises for compressor dehumidifiers with just a slight increase in power consumption, hence why they more efficient in warm rooms.

The running cost will be the highest in the first month or two as it removes a bulk of the moisture from the rooms, furniture, etc. For the first week, a desiccant dehumidifier will likely remove 3 to 6 litres a day (depending on its setting and how soon it's emptied once full). After that, the rate will gradually reduce and probably fall to around 1 to 2 litres a day once the humidity is under control.

Based on Electric Ireland's standard rate of 17C/kWh, 1 litre (2 kWh) would cost 34c. So at the start, it will probably cost about €1 to €2 day and drop to around 34c to 68c per day once under control. It's also worth noting that a dehumidifier warms the room by few degrees while it's running, so the cost will offset the heating cost, particularly if you use any electric heaters. For a compressor dehumidifier, half this cost for summer time use, i.e. 20+C operation.

Finally, avoid using "moisture absorber" single-use units to collect moisture. It's surprising the number of hardware stores I've seen with them at the store entrance claiming to be a solution for controlling damp in the home. Their refills work out around €2 to €5 per litre collected!

DubInTheWest

editorsean wrote: »

At around 15C, I reckon that both desiccant and compressor based machines have about the same power consumption per litre collected, i.e. around 500ml collected per 1kWh of power consumed with the air humidity about 60% RH. The extraction rate increases as the temperature rises for compressor dehumidifiers with just a slight increase in power consumption, hence why they more efficient in warm rooms.

The running cost will be the highest in the first month or two as it removes a bulk of the moisture from the rooms, furniture, etc. For the first week, a desiccant dehumidifier will likely remove 3 to 6 litres a day (depending on its setting and how soon it's emptied once full). After that, the rate will gradually reduce and probably fall to around 1 to 2 litres a day once the humidity is under control.

Based on Electric Ireland's standard rate of 17C/kWh, 1 litre (2 kWh) would cost 34c. So at the start, it will probably cost about €1 to €2 day and drop to around 34c to 68c per day once under control. It's also worth noting that a dehumidifier warms the room by few degrees while it's running, so the cost will offset the heating cost, particularly if you use any electric heaters. For a compressor dehumidifier, half this cost for summer time use, i.e. 20+C operation.

Finally, avoid using "moisture absorber" single-use units to collect moisture. It's surprising the number of hardware stores I've seen with them at the store entrance claiming to be a solution for controlling damp in the home. Their refills work out around €2 to €5 per litre collected!

Thanks very much for all that. I'm pretty shocked on how much it costs to run. I had an idea it could be pretty expensive but wow €2 a day!

I thought that I would need to use a dehumidifier for a few months to clear up the issue, but it seems this could be a lifetime kind if thing to keep things on an even keel ?

I'm leaning towards a desiccant dehumidifier at this stage. I'm not 100% sure if the temp will drop below 15c, it's possible it might and also I'm sure my wife will put it to use in the outhouse at night to dry washing just to make use of it. I'm just assuming it will be too noisy to leave in the bedroom while sleeping.

Thanks again for that, my mind is just about made up, I just need to find a good dehumidifier now

editorsean

From a quick check, the cheapest desiccant model I've come across is the Igenix IG9807 on Amazon, £112 (approx. €130). It's sold by Amazon, so should have free delivery to Ireland.

It looks identical to the Trotec 55E at my workplace, so assuming it's the same machine apart from the brand name, it collects roughly 300ml per hour on high and 150ml per hour on low at about 60% RH based on my usage. It has a 3 litre water tank which is nice. Most desiccant dehumidifiers only have a 2 litre water tank. The only drawback I found is that the relative humidity cannot be set (fixed at 45% from what I recall), so you'll need a hygrometer to keep an eye on the humidity level. After the first few weeks, you'll probably get away just switching it on for a few hours a day. It has a built-in timer that can be set to switch off after 1, 2, 4 or 8 hours.

If you have not switched electricity providers in the past 12 months, this would be a good time to find a cheaper provider. If you go for one with a free credit offer (e.g. Bord Gáis's €100 offer), that would take care of the initial running cost, after which the cheaper unit rate will offset the on-going running cost keeping the humidity under control. Alternatively you could go with let's say Switcher.ie's Energia's offer (12.85c/kWh) that would take a good chunk off the initial running cost, the on-going cost and a good chunk off other electrical running costs such as the tumble dryer.

DubInTheWest

Just want to post a quick update on this.

I received the dehumidifier a few days ago. I was going for the linked version but it went back up in price so instead I got the trotec ttk 50e.

I've had it on continuously day and night since I got it and just from today the damp/mildew smell is actually nearly gone. At first it was pulling about 4.25 liters per 24 hours, now its about 1.5 liters per 24 hours.
The only thing I'm lacking is the hygrometer. There isn't one built into the machine but I ordered one from amazon which will be here in a few days but until then I have no idea what the humidity is.

I will say my breathing has really improved right from the outset. I do suffer with a lot of allergy's and my breathing in general has never been better. But more importantly it seems to be doing the job.

I'll leave it a few more days in the bedroom and then probably move it out onto the landing and see how it goes out there.

Thanks again to everyone who gave me information

cobham

Delighted to hear a result for you. We leave ours on half landing. Don't locate up against wall..... 10 inches or so to let air circulate. Ours is across a corner.