Workshop heating( sorry to raise it again)

[Martin Murray 2Participant @martinmurray2]

The workshop is a cabin 1.25"thick interlock board — wood floor covered –not insulated walls or ceiling Has been generally dry but noticed that as soon as temp by radiant heater heats shed above 12 C ,condensation forms on cold surfaces causing surface rust on some tooling . Ok I know the moisture if from the interior atmosphere and the heating causing the dew point to be crossed Propose to solve the situation as follows. Mount an ir panel 3000nm – this doesn't heat the air but heats surrounding objects and keeps them at 80/90 f. The panel consumes 300 w which would be fed by a 12 v battery using inverter to convert to 230/240. Battery kept charged by solar panel on roof. Ir at this frequency is not hazardous to health but according to manufacturers spec would eventually bring the temperature inside the workshop to a nice 60/65 ambient working environment. The unit would be on 24/7 maybe switching off in summer. What I would like to know if anyone has had experience of ir heating at 3000nm frequency? . This system is totally green and not reliant on wiring to shed. Thanks for any replies

L

[Martin Murray 2Participant @martinmurray2]

ir panels

[Gordon WParticipant @gordonw]

I must say that I don't know the answer. I have been looking at these sort of ideas for some time and have not reached a conclusion. Having said all that I think you would do better by running a small de-humidifier, this also will warm the air. I have not done any maths ,except back of envelope , so have no proof.

[Nick_GParticipant @nick_g]

.

What size are the solar panels.? And the battery that will have to see the heating through the dark of night.?

Not an expert by a long way on this, but I cannot see this stacking up.

Nick

[Bob Brown 1Participant @bobbrown1]

I think part of the problem may be the wooden structure it's self, wood is a hydroscopic material and will take on and release water as the temperature varies. I would be inclined to fit a desiccant dehumidifier, power consumption is probably overall going to be less than the IR option as it will switch off at a pre-set humidity level say 40% but will need a supply capable of around 750watts, normal usage closer to 300watts, so still an option for solar power.

Bob

[Martin Murray 2Participant @martinmurray2]

The ir panel consumes 300 w and is rated over 80percent efficient.the inverter runs at more than 70 percent efficiency. Ok so accordingly if my maths are correct total consumption is around 2-21/2 watts.100 amp/ hr battery would run system 24 hrs . The ir supplier suggests switch on/off 50 percent of the day/ night . Assuming then the battery would last 48 hrs without charge. A 100 w 12 v is the proposed solar panel which sould be enough to keep the system going. There could be alternative to the panel —and that is using 3000nm diodes to generate the ir . These are easier now to obtain but have problems in controlling but use much less power.

[Hamish McNabParticipant @hamishmcnab62554]

2-21/2 watts ?? This time of the year you are not going to get a lot out of your solar panel. What is your estimated total power consumption, and what temperature are you anticipating this system to raise what size of workshop? If your solar panel managed 100w then that's not a lot of heat.

[Neil WyattModerator @neilwyatt]

Hi Martin,

Welcome to the forum, apologies in advance if this comes across as a bit negative, but I wouldn't like you to invest several hundred quid and discover that it doesn't work.

I'm afraid that you will need a lot of solar panels. In simple terms think about how much the sun heats the roof of the shed on a winter's day – not enough to make it feel warm to the touch. A roof-sized solar panel can't get more energy than that, so you would need to cover amuch larger area with panels.

300W may not seem a lot, but on 24/7 is 7.2 kW hours a day, which is 600 amp-hours at 12V – that means you need enough solar capacity to charge ten car batteries during the eight hours of weak daylight on an overcast winter's day. One website estimates that a 100 watt-hour panel will only generate one 100 watt hours on a dull winter day – only enough to run your heater for twenty minutes.

You could be better off getting a solar water heating system for the house, and using the fuel savings to insulate and heat the shed.

Neil

[Dave HalfordParticipant @davehalford22513]

I'am afraid Bob Brown is right — it's the wooden shed.

Giant B&Q sites do 25mm thick 8 x 4 sheets of polystyrene for £7 each totally lining the shed will

1. prevent the wood from affecting the inside air during the damp days of winter.

2. Help sound proof it

3. Not cost a lot

Then all you need is a light film of oil on exposed metal

[Les Jones 1Participant @lesjones1]

Hi Martin,
First I do not believe the figure given by the IR panel supplier of maintaining a temperature of 60/65 Deg F If they had done their calculations the would only be able to say it would raise the temperature so many degrees above the outside temperature. My shed is a brick outer skin then a 2" gap then thermalite blocks. 300 watts would not hold the temperature any where near 60/65 Deg F with an outside temperature of say 5 Deg C (41 F)
Like Hamish I do not understand "3-21/2 watts" This is how I would do the calculation. In winter it goes dark at about 16:00 and gets light at about 08:00 So you have 8 hours to charge the battery and the battery needs to provide 300 watts for 16 hours. This is 4800 watt hours (Assuming a 12 volt battery 400 AH capacity) To replenish this in the 8 hours of daylight you would need 600 watts from the solar panels plus the 300 watts to power the IR panel during the day so you need a 900 watt solar panel. I do not know the cost of the solar panels but a 40 AH car battery is about £40.00 so you would need about £400.00 worth of batteries. Even if you use the heater with a 50% duty cycle (ie half the above calculation.) it is still a high capital investment. I think using a dehumidifier as already suggested would be better as you would gain the latent heat of evaporation of the water condensed.

Les.

[Bob Brown 1Participant @bobbrown1]

Solar would probably work for shed lights but for anything else pushing it a bit.

Most of the renewable options make me laugh, they never give the output quoted by some margin (20% on a good day), thrown in to that mix is the fact you need the power when there is no light. You only have to look here **LINK** to get an idea of daily power consumption, and solar is to small to measure or it maybe all the little inputs are not counted.

At night solar is useless, wind is only good when the wind blows, not enough wind or too much no power generated and you still have to have capacity in the system to cope with these situations.

For once I think the French have it right, 80% nuclear, we moan if the are going to build anything doubt the complaints will be so hi when the lights go out or you have to revert to pedal power to machine the odd bit of metal.

Bob

[Jesse Hancock 1Participant @jessehancock1]

You might like to talk to boaty people on this one since this is always a problem on a wooden boat. Take a walk around any marina at any time of year and you will see they will have the front hatch open all be it just a bit and one open at the far end of the boat.

It is hoped that this will induce a stream of air through the boat sufficient to keep her reasonably dry and at an ambient temperature with the outside. Not forgetting that they have to have water in the bilge to keep the planks swelled and the boat water tight. IE no hope of drying out completely.

If you continually wet and dry wood it will rot very quickly. Note the boats on hard standing having water line planks renewed.

I think I would settle for an electric fan heater when feeling cold aimed at ones self and a store of WD to disperse the damp from machinery and spray at the end of play.

Leave a window or two open just a tad…. I'll bet you you're thinking what about the burglars!!! Truth is if they want to get in they will find away. I also think Harvey Kietle is wrong saying fit a burglar alarm since it takes the cops about two days to respond around here. This is just my opinion of course.

Jesse

[Martin Murray 2Participant @martinmurray2]

Thank you all for your response — it gives food for thought. The information on these new infra red panels working at 3000 nm was given by the manufacturer—"""""Standard convention heating systems either radiant or hot air expend a lot of energy to keep the ambient temperature up all the time– not practical for a not well insulated building. Infrared at this frequency releases energy on contact with a surface it doesn't waste energy heating air molecules. Objects in the building and the fabric itself collect the heat – warm up and then emit the heat back eventually creating a stable comfortable temperature."" A panel suitable for a shed 12 x12 would be 300 watts.—– what I am trying to achieve would be to supply that power for 50 percent of the day as the recommendation is to operate one hour on one hour off . Apparently it only heats objects not the surrounding and I have been told that working in the shed I also would be an " object" and so would receive infra red heat . It is said to be like the sun where you can sit out in snow field but the infra red from sun will warm providing there is no cooling air. So if it warms objects it is supposed to prevent condensation.

[Martin Murray 2Participant @martinmurray2]

Thank you all for your response — it gives food for thought. The information on these new infra red panels working at 3000 nm was given by the manufacturer—"""""Standard convention heating systems either radiant or hot air expend a lot of energy to keep the ambient temperature up all the time– not practical for a not well insulated building. Infrared at this frequency releases energy on contact with a surface it doesn't waste energy heating air molecules. Objects in the building and the fabric itself collect the heat – warm up and then emit the heat back eventually creating a stable comfortable temperature."" A panel suitable for a shed 12 x12 would be 300 watts.—– what I am trying to achieve would be to supply that power for 50 percent of the day as the recommendation is to operate one hour on one hour off . Apparently it only heats objects not the surrounding and I have been told that working in the shed I also would be an " object" and so would receive infra red heat . It is said to be like the sun where you can sit out in snow field but the infra red from sun will warm providing there is no cooling air. So if it warms objects it is supposed to prevent condensation.

[Bob YouldonParticipant @bobyouldon45599]

Hello all,

I've worked out of the same wooden workshop for more than thirty years at our present address and I've never been troubled by damp or rust . When I built the workshop I included a vapour barrier, 50mm polystyrene block infill, all finally covered with an insulating board. The heating is via a thermostatically controlled fan heater set on its lowest setting, timed to come on twice a day, for an hour between 05.00 and 06.00am and again in the evening between 18.00 and 19.00pm. The essential component is maintaining air circulation, too many people experience condensation problems when the simple expedient of a little air movement together with a little heat will eradicate the majority of their problems. By introducing sufficient heating into the workshop those most valuable of our items the machinery, material stock etc, the mass of which also absorbs heat helping to avoid the dew point, at which condensate settles out on all that expensive machinery and turning everything brown. We pay fortunes for our machinery and tools, its not a big price to pay to look after them by a little heat and importantly air circulation.

There are a number of excellent heat recovery / ventilation units available, which will provide adequate levels of ventilation whilst recovering the heat from the waste air stream whilst introducing fresh warmed air into the work space.

Regards,

Bob Youldon

[maurice bennieParticipant @mauricebennie99556]

Hi All I have one small oil filled rad with thermostat turned to hold temp. at about 10 degrees,plus one small dehumidifier (drains off about 100 mil per week) depending on weather ,That's maximum amount. Humidity is between 60 to 70 on my meter. No rust in 5 years ,Cabin 3×4 meters with 1 1/2" walls insulated with CELON sheets ,roof with 4" fiber glass, Happy with that ,it's working for Me.

Maurice

[Hamish McNabParticipant @hamishmcnab62554]

Martin, there is no free lunch you only get out what you put in. If it's 300watts then that's three 100w lamp bulbs. Will that heat your shed to 60* odd?

[BazyleParticipant @bazyle]

This is the best renewables forum in the uk. although it is run by a company they are very hands off like here.

Battery – no chance. You can barely keep the lights on with solar. A lead acid battery, even a deep discharge one (which is a total con anyway) must not be discharged more than 50% if you want it to last more than a month. The deep discharge bit just means you can get away with it a handfull or times rather than just once with a regular battery.
You need to make it totally airtight, then run a dehumidifier that has a compressor off the mains. The ones <£100 that use a peltier are rubbish. The ones that use some kind of dessicant are also rubbish.
While you are doing the 1 in of insulation you might as well do 2 in.
if you have uncontrolled ventillation it just lets more damp air in when the orignal air has condensed all its water. It needs to be controlled and only opened when you are in there or it is very dry outside.

[Ketan SwaliParticipant @ketanswali79440]

Hello Martin,

A while back we used to attend shows. One venue in particular was a big converted farm barn/shed with no heating over night, and no de-humidifiers at the time. We used to leave machines on display over night to find them covered with fine film of rust in the morning. Then we would franticly clean them before visitors arrived.

Then we started covering them with a product called Metalguard Ultra from Shield Technology. (WD40 was a serious waste of time). See this link:

**LINK**

We used to sell this product, but we don't now due to certain commercial reasons. However, we still use their products on all the machines we have on display in our showroom. You cannot see the product on any of the milling tables. You use the metalguard ultra sparingly by putting into a garden spray bottle or small spray bottle of some description, and spray a very very fine mist over the table for example. It spreads, leaving a film on the product of about 2 microns, protecting your worktable and/or tooling. Even though our own display area is warm above 17 deg.C, it protects these surfaces from 'rusty fingers' of visitors wishing to see, feel, touch the machines.

At the shows, we also used Shields VCI pots inside display cabinets to protect the tools on display from the film of rust. It is often used inside tool chests..

I always promote the use of their products because I know they work, if you decide to go down this route. There is no monitory gain by my promoting them. I am just happy to plug a great value product made in Britain.

Ketan at ARC.

[Neil WyattModerator @neilwyatt]

Solar panels are no good for applications which require direct energy supply in the winter as they are a seasonal source of energy. Nothing to do with Bob's claim of only 20% of rated output – a 250W panel on a narrowboat will run TV, lights and keep the starter battery topped up all summer.

We only get 1/6 as much energy from the sun in winter due to seasonal variation, so as a first estimate you need six times as many panels in winter.

A 300W IR panel fed by a 70% efficient inverter will use 428 watts from the battery.

Even assuming battery charging is 100% efficient, to run the panel for 12 hours a day will use 428*12=5142 watts.

Now as its dark winter days that means you need about 5 kW of solar panels, typically what you would have to power a house.

The difference is the house panels feed the excess into the grid in summer and you take extra out of the grid in winter and at night.

Neil

[BazyleParticipant @bazyle]

Some rather ungood reviews for metalguard on this suppliers' site just as I was about to thank Ketan for the advice. I must say it is good to see a supplier who will allow negative reviews to stay on display like that.

My preferance for decades for rust prevention on non-sliding surfaces, stock material, derusted tools etc is dilute clear Waxoyl or equivalent. Pleasant to touch and fairly permanent but does collect and hold dust after a while.

[Ketan SwaliParticipant @ketanswali79440]

Hi Bazyle,

I saw the 1 star treatment too

I don't know why those reviewers had that experience. I can only qualify the experience I have had as follows:

1. When I first started attending the shows – about 10+ years ago, I didn't know anything about protecting the machines overnight and in transit/storage pre and post shows. I watched the competitors spray their machines with WD40 at the end of shows for the onward journeys back home. So, I did the same. Nice and cheap. On one occasion, I left the machines overnight in the Luton, as it was cold and wet outside, and I didnt fancy offloading at night in this weather. In the morning took the machines out to put back into our display. Removed the transit shrinkwrap, and still saw some rust film on exposed surfaces. Some expletives later, cleaned and oiled the machines. My team and I have many such experiences with WD40. Finally, Paul Price from Shield came along and introduced us to Metalguard Ultra, which initially we regarded to be an expensive gimmick. We proceeded to try it and found it worked. This was also used as part of our preparation service when we used to offer it. As soon as machines were prepared, we sprayed them with the metalguard to avoid transit rust, be it to destinations in U.K. or Europe, because we had no idea of transit/storage conditions. We even suggested it to SIEG, but they considered it to be too expensive for transit protection. they preferred the white grease or red grease (lovingly referred to as chicken fat)

2. Originally before we discovered metalguard, we had to regularly clean our display machines and wipe the tables with oil soaked rags at least once a week, depending on how many visitors had been and touched them. Once we started using metalguard, we clean our machines once every two odd months or if needed, followed by a fine mist treatment with metalguard. Before, rusty figures were quick to form marks on exposed surfaces. I admit that the temperature is above 17 deg.C, but still, rusty figures are rusty fingers. For colder temperatures the user might have to clean/apply metalguard more often maybe, depending on various factors, but in my opinion, this stuff protects far better than WD40, for sure. As the spec. on Shields site says: it complies with defence and NATO standards. We have been using it now for well over seven years, and we are happy with it.

This product had also been well tested by one of the largest specialist woodworking tools companies in Germany over an extensive period before they got the confidence and comfort to buy it from Shield and sell it. Their purchase volumes from Shield are very high.. Similarly, their sales into USA have also grown over time.

Initially, we were the only main U.K. seller for their product. Then Axminster came on the seen, purchased from them and our sales for this product reduced by 50%. A year later, machine-dro started stocking SHIELDs product to complement their Ultrasonic tanks related product range, resulting in a further drop in our sales. We are in business to make money, just as SHIELD and others are. If the quantity of sales become nonviable, as they did at the time, it is difficult for us to invest in advertising and promoting their product in the way we did at the time, pre the competitors. We had certain verbal agreements at the time which failed, resulting in the commercial decision to drop the product at the time. Our and SHIELDs position today is different to how it was for both of us at the time we dropped their products.

Whatever the commercial reasons, I am still comfortable that their products work. Their products are much more popular now, and I feel that too speaks volumes and should be taken into consideration, if we are to make any judgement on quality….and they hardly do any advertising or marketing of their own. SHIELD is a small British business which has come a long way.

They also do a wax polish which works.

At the end of the day, we all have our own experiences.

Ketan at ARC

[DMBParticipant @dmb]

Hello all,

Here in Brighton, a lot of parking ticket machines are battery powered and charged up by the solar screen on top of the machine.

At this time of year with day after day of cloud gloom, meters stop issuing tickets and return the coins.

John

[Trev TParticipant @trevt]

My workshop consists of a precast concrete garage, standard 16'x8'. It was refurbished a couple of years ago, when the original corrugated asbestos/cement roofing was replaced with Kingspan insulated panels. Apart from that, no other insulation has been installed, the walls just being covered with white masonry paint. The floor is unpainted concrete (painted floors generate condensation), laid on a dampfroof membrane, on hardcore, ABOVE surrounding ground levels . ALL eves gaps have been closed and draught strips fitted to the double wooden access doors that are at one end. My machinery is very lightly oiled, as a precaution, but handy files are not (naturally), nor are hammers and pliers, etc. In Winter, I do not 'heat the workshop', but run a cheap dehumidifier (24/7) that has a powerful air flow out of a vertical outlet that circulates dried air throughout the 'shop. A small (set at 600W) fan heater is positioned to blow across the front of the dehumidifier (inlet grill), it's thermostat set so as to maintain the min'm inlet temperature required by the dehumidifier, around 4 degs C locally, to avoid the possibility of icing-up the heat exchanger coils. The phylosophy behind this is to AVOID heating the air in the workshop to the point where it can support higher moisture retention. Any bare wood in the 'shop (there is a small stock) has been dried out to the ambient levels sustained, as has the bare concrete floor (I do use domestic doormats to stand on in strategic positions). I couldn't say that the building is completely airtight and that I gasp for air when in there, but the dehumidifier is powerful enough to deal with any leaks and, of course, my exhaled moisture! I do open the shop doors and window when generating fumes of any sort, but I do try and arrange such activities around drier outside atmospheric conditions. If I am planning to work in the 'shop during very cold weather I usually nip in there early and 'jack up' the thermo' on the fan heater, it has a higher output of 1.6kW, to lift the temperature modestly (I don't need to work in simulated summer-like conditions, or attire!). Lifting the temperature of dry air is not going to create undue condensation on cold metal, and the warmer air only makes the dehumidifier more effective anyway. However, care is taken when starting cold motors…!

Summarising, then, I don't have rusting in my 'shop! The dehumidifier collects about 4 litres of water every 3 to 4 days, which is both startling but gratifying and which dispels any thoughts that dessicant alternatives might be cheaper!! I consider that the cost of running this system is well justified, given the value of the contents of and the 'shop as a whole!

Trev T

[ChrisHParticipant @chrish]

My workshop is roughly 2.5 x 3.7m. The outside walls are about 400mm thick of lumps of Ham Stone held by earth, with mortar pointing on the outside and a sand/cement render on the inside. There is one double glazed smallish window – about 1 x 0.8 m – and a single non-insulated wooden door. The apex roof is close boarded wood with roofing felt and pan tiles over and 6in space blanket then boarded with thin T&G strips under

I run a small dehumidifier, sometimes continually, sometimes on a humidity setting plus two Cold Watch 500w electric heater set on just above frost stat level. This maintains the workshop at between 5-8 deg.C. If I am away only the electric heaters run as the dehumidifier is not on constant drain – that is on my "to-do" list! When I am working in the shop I have a small fan heater set to fairly low on a one kW setting, or I can run a wee log/charcoal stove. The shop very heats up using either, by 60deg.F it is getting too warm!

I have not found any corrosion on any tool in my workshop since I started with in about four or five years ago, so I am happy with what I have in place, it works for me and the cost although not accurately measured is low.

Chris

Edited By ChrisH on 20/02/2015 10:55:57

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