HotBin frustration!

[PatW]

I’ve had a HotBin for a year and still haven’t had a decent heap of compost. The first heap was just passable. The second heap was anaerobic, despite putting in paper, bulking agent and hot bottle. On the third attempt the bin was cleaned out and dried, small sticks and shredded office paper put in the base followed by a 50/50 mix of kitchen waste and shredded office paper and cardboard and small amount of bulking agent. The result was a wet smelly mix. So I cleaned out the bottom and mixed it with more paper and put it back. Cleaned out most of the top and mixed that with more paper and card. Put the hot bottle in and covered it with the mix and some shredded paper on top. Next day it was barely warm.
I’ve come to the conclusion that I bought the bin under the illusion that it was going to be an easy and quick way to make compost. Clearly it isn’t, just very frustrating!
I’m going to give it one more try. If it fails again then I guess my options are to keep an expensive storage bin, find a buyer or make a trip to the recycling centre. Meanwhile I’m setting up a second wooden compost bin as I always get results from that.

[nortonbeak]

My very inexpert opinion is that you just are not getting sufficient air flow through your compost. When I use the kick start bottle, I get a fairly rapid temperature rise. I put that down to air flowing up through the compost.
I suggest you carry on trying using more bulking agent and ensuring you are maintaining a good chimney effect.

[PatW]

Thanks for that. I tried doing that yesterday. The bin is about 3/4 full so I took out about 3/4 of that and mixed it with bulking agent giving it all a good stir as it went back in and covering the replenished hot bottle. I have looked today and the temperature is 10deg. There is some leachate visible on the slab the bin is sat on but nothing near the amount there has been in the past so doubt the mix is too wet. I took the charcoal bag out of the lid yesterday, it wasn’t sopping wet but left it out to help airflow. I noticed today that the inside of the lid was wet so maybe that was caused by the rise it temperature yesterday when the bottle went in. The vent is open 2mm as recommended.
I’m no brain of Britain , but I do have a science degree . I just do not know how to get that bin going ( apart from down the road!)

[PatW]

Here I am again, just as frustrated! Yesterday I cleaned out the bin and refilled with a small stick layer, well mixed kitchen waste/shredded card/paper/ bulking agent and the hot bottle. That took the fill just above door level, in anticipation of filling it a bit more today. But today the bin is not hot so I’ve put a bit more fresh kitchen waste mixed with chicken pellets. Here’s hoping.

[PatW]

Update. The HotBin is cold again. Have refilled the hot bottle, given the contents a good stir and added a small amount of kitchen waste with some shredded card.
if anybody has any suggestions they would be most welcome!

[Hotbinner]

Is the leachate full? Try leaving the cap off if you can to encourage air flow

[Black Jasper]

I understand your frustration as have been there myself! I've had loads of good compost since June when I started. It seems for me necessary to remove mature compost about every 6-8 weeks. I found that quite tricky as I find when I get to the back of the wedge the top partially decomposed falls in and makes quite a mess. I realise now with the benefit of hindsight that I had probably left too much residue leading to clogging of the air conduits. The temperature was fine in the summer but has been much more difficult in the winter. I had no leachate initially but now have masses. I have added a hot water bottle every day for the last month but still around 20-25 C only on the lid thermometer. Yesterday I cleaned out the whole bin removed about 50 L of stickyish but good compost. Found base plate completely clogged with debris so cleaned this thoroughly(each hole separately unplugged all 192!) then rinsed under the tap . Also thoroughly drained reservoir and cleaned out accumulated sludge Added 20L of shredded cardboard 10 L of twiggy wood shavings/bulk and replaced semi-digested 50L or so of residual compost . Today temp has risen to 38C so I am feeling a little more optimistic. I would be very interested to hear of your further progress

[PatW]

Thankyou for that. A few days ago I gave the bin a good raking and it did warm up but needless to say cold next day. I cleared the bin and cleaned the sump about two weeks ago and have tried to put a good mix in ( twiggy layer in bottom) it since then so I don’t think the sump is full or blocked.
Today I’ve taken most of the waste out (from the top) given the remainder a good raking, filled it with a mix of shredded cardboard, kitchen caddy waste and some of the fill that was in the bin and the hot bottle, nestled near the bottom.
Next to the bin is two bin fulls of anaerobic waste I have taken out of the bin. It’s covered to keep the rain off , when the weather is better hopefully it will dry out. For sure what I don’t want is another heap of the stuff!

[Black Jasper]

Dear Pat W,
It all sounds familiar. It has been very wet recently. I think water tends to seep in which presumably makes the contents too wet and interferes with the air flow. It could be worth putting a cover over the bin. I have found that it seems almost impossible to add too much shredded cardboard. This seems to absorb some of the excess water and seems to reduce the stickiness of the compost. I find that with this method the lid reads 30C, the short surface thermometer = 50 C and the deeper thermometer at 20cm = 30 C. I have a good rake each day which always seems to generate some heat and steam. It seems to me if one can keep the air flowing through then there is much more likelihood of seeing the thermometer rise....one lives in hope!

[PatW]

Hello Black Jasper
I hope you are having more HotBin luck than me! I gave mine a good raking a couple of days ago, then again the following day but it’s cold (9c) today. So I’ve dug out most of the contents to retrieve the bottle. Raked the remaining contents in the bin and put the hot bottle in. Covered it with a large trug of the emptied contents that have been raked and more shredded card added. Here’s hoping....
Meanwhile, plan B into operation and have bought 2x dumpy bags of compost . The ‘other half’ has been commissioned to make a twin wooden composter!

[Dianeliz]

Hello, I’m new and am awaiting my bin to arrive. I’m expecting to have to learn a lot.. I was reading this, and, in the past I tried a wormery and put loads of kitchen waste in. It was hopeless and never really worked. But when I asked around everyone said I needed to flesh it out with more garden waste. The kitchen waste alone is tricky I think, maybe it needs to be hotter for that? Just a suggestion though... I don’t know anything 😀

[HotBinDjinn]

Here are some things I’ve found over the last two years that have impacted the temperature of my bin.

Outside temperature – if it’s really cold, the kickstart bottle doesn’t always work – wait until it’s a bit warmer.

Air Valve – Don’t open it too far or you will lose heat. If you are using the kickstart bottle the air valve needs to be kept closed for 24 hours, as per instructions.

Give it time – Even with the kickstart bottle, it can take 4-5 days for the compost to get to 30 degrees. If you continually open the lid to check, you will lose any built up heat. Put the kickstart bottle in there an leave it.

Shred size – If you are using shredded paper and cardboard, make sure the shed size isn’t too big. Full length shredded paper can create a layer of mulch that stops the air flow. Make sure whatever else you are composting is chopped up. Reducing my shred size has given me a constant temp range between 45 – 55 degrees and I’ve even reached very close to 70 degrees at times.

Emptying The Bin – Don’t empty the bin in cold weather if you can help it. Even the ready compost holds a decent bit of heat and if you remove too much of it, the temperature of the rest of your mix can fall significantly.

If the compost is going anaerobic, it’s too wet, which doesn’t help with air flow problems. This is the case with hot or cold composting. Also, I wouldn’t put any cooked food or anything smelly near my composter until it’s at least 40 degrees. Make sure your bulking agent isn’t too wet.

[nortonbeak]

Hello HotBinDjinn

Thank you for sharing your hints and tips with us.
I believe that the forum was created for that very purpose. I am sure your advice and experience will help us all.

[clare]

hello HotBinDjinn, Thank you for your advice but can you tell me where it says to shut the air valve for 24 hrs when you add the hot water bottle? I am having difficulty getting the bin hot enough. I was given it at christmas and have at least 40cm of waste but cant get it hot enough even with the bottle... but I haven't shut the valve for 24 hrs. thanks

[HotBinDjinn]

hello HotBinDjinn, Thank you for your advice but can you tell me where it says to shut the air valve for 24 hrs when you add the hot water bottle? I am having difficulty getting the bin hot enough. I was given it at christmas and have at least 40cm of waste but cant get it hot enough even with the bottle... but I haven't shut the valve for 24 hrs. thanks

Hi Clare,

I'm sure I read it somewhere or heard it in a video - there are several on YouTube I've watched. I could have been mistaken, and I don't seem to have any of the user guides that came with the bin anymore. Having said that, I've used the kickstart bottle a couple of times, once after being on holiday and just the other day after taking out too much compost (and removing most of the thermal mass). Both times I kept the vent closed for the 1st 24 hours and it worked perfectly. My bin is sitting at a constant 40 degrees.

The bin can still take several days to heat up, so even after the 24hours I would advise to keep the bottle in there, open the valve but not open the lid for several days. The bottle doesn't get the temperature up straight away, it just starts the reaction, which can take the best part of a week just to get to 40 degrees. Outside temperature can make it more difficult, but not impossible. Depending on your ingredients, your might just need a little more material.

Are you using the external thermometer to measure the temperature? I find this isn't very accurate unless the compost is near the top of the bin. Its reading can be off by a wide margin. My compost is 40 degrees, but the reading in the external thermometer is only 20 degrees. As long as your material isn't stinking, you can be patient and keep adding material before trying again.