The isses we have face as we went alone this road of waste oil heating.
We started by finding this waste product could be burnt, and burnt for a very long time on a very small amount, but not cleanly without assisted air. So years down the road, we introduced forced air via a fan. After 30 different fans later we found the correct one.
This fan cleaned up the smoke levels, so we had a heater that could operate cleanly, great we thought, now we can go the next level and look at heating water, so we added a copper coil. That worked well.
Now we can heat any area for next to nothing, and swimming pools all good we thought. We struggled to keep them to a set temperature with taps and even precision needle valves. We worked out as the oil change consistency as it warmed up it flowed faster, causing the heater to increase temperature without even touching it or in some cases without even knowing it was happening. The drip fed units were the worse, you could walk away from them and 5 minutes later the heater would be glowing red at 1200 degrees c.
Something had to be done about introducing power, and a pump to regulate the oil flow, not that we wanted to introduce power as that's not free heating, but we had to control that oil.
We played with multiple timers and pumps, we soon found the one we needed, and an oil pump.
Over the last two years we have been looking into safety of these waste oil heaters, and the only option we found was to introduce a small amount of power to run the 12 volts 5 amp electronics to keep this heater under full control. Without any controls they can become very dangerous as we found out. What amazes me is there is one or two guys on Youtube that have invested in safety features with these heaters and there are thousands of guys who have built their own with no safety features at all.
A timer and pump sorted out most of the temperature changes, but in the back of my mind was, if the flame ever went out from some unforeseen problem, the oil would continue to flow, until it flowed out the heater over the lawn into the pool etc, and spilt oil is the worst stuff to clean up. So as from today 1/5/2018 we are introducing a digital thermostat, and this will turn the oil pump/ flow off, if either the hot water or fire drops below 40c. This temperature can change to suit your situation by pressing a couple of buttons.
Now and only now we have the fail safe waste oil heater.
I don't know what's the next issue where going face, hopefully we can overcome it as we have done in the past.
I have posted a video of the thermostat in action below. Works very well.
We have been running with the thermostat timer and pump, wow what an excellent heater, we have town supply water going into an ajax valve and a open vent, should pressure build up in the loop, the vent lets it go, and the ajax valve fills it up automatically so the loop never has pressure, and can never run dry.
I runs very clean and to a set temp just brillant, should anything happen it will shut down.
It's peace of mind, now we know it won't do anything odd so we really never even check it, just light it and turn it off.
But we still get questions which never came across.
I have had two customers who have come back to us, saying they can't keep the waste oil going, once the rag has burnt the flame goes out. The issue is your introducing cold oil into a cold pot, this in itself will put the fire out as oil takes a far bit to get going, Our advice use a gas torch for one Mapgas is great, or put 1/2 cup of kerosene in the pot and light it, start the oil flow once the pot heats up, and if it still needs a wick then throw in a few old nuts and bolts for the flame to catch on.
Once you get the hang of getting the heater going then these nuts and bolts may not be required, just the rag will do or even a small piece of scrap cardboard and pour 1/2 cup diesel on it, works well every time for me.
Now don't get too upset if the odd thing goes wrong, because it can so it's not just you, timers can become faulty, or you've alter them and finding it bloody impossible to get them going as it was, we have had 1 oil pump faulty so just get back to us, we normally have everything in stock so in most cases it's a courier bag fixers the issue.
I had an issue when I change the 44 gallon drum over. I tiltered the drum and pumped the remainder of the oil out, it was very watery and thick and as soon as it reached the heater the smoke was bad. I turned the heater off, and was very annoyed that I even used that oil.
So I removed the oil from the 20 litre container and pumped new oil into the oil line for a few minutes and collected about a litre of that oil, re-lit it, and yes we were back to clear heatwave once again Yah. So I popped the thick watery oil back into a 20 litre container to take it back to be recycled
So don't use that thick watery oil at the bottom of the 44 gallon drum, In a way I'm glad I found out about it so I could post it on the website. Just another issue cleared up.
Now i've been thinking thermostat to stop the heater for when say a spa pool reaches 40C or the calf water 37C, but I'm going to try and find one which won't turn back on when the temperature drop below 40C or the setting.