Anyone got direct experience of indirect heaters?

[JOEPRO]

But rapidly heating and cooling a room could cause real condensation issues
Sounds like it will be heated rapidly, and depending on your insulation I think it will cool rather rapidly too once you turn the heater off.

So what to do - no heat(?)

It's a masonry cavity wall construction garage it'll be great. I can also have the cavities pumped with insulation this summer then get the pitched roof loft spray foamed at some point too.

 

[Pigeon_Droppings2]

I can also have the cavities pumped with insulation

Not sure I'd be doing that myself...I've heard it's wonderful when it works but it can also cause problems.

 

[offthames]

So what to do - no heat(?)

It's a masonry cavity wall construction garage it'll be great. I can also have the cavities pumped with insulation this summer then get the pitched roof loft spray foamed at some point too.

Think with it being insulated in due course a diesel heater would be ample although won't heat up as fast. What is short evening use, 1-2 hours? If you're running a diesel heater you could remotely start it up say 1-2 hours before you plan to go in. Think you may have jumped the gun especially if you plan to get the place insulated.

 

[JOEPRO]

Think with it being insulated in due course a diesel heater would be ample although won't heat up as fast. What is short evening use, 1-2 hours? If you're running a diesel heater you could remotely start it up say 1-2 hours before you plan to go in. Think you may have jumped the gun especially if you plan to get the place insulated.

The insulation won't make much difference. It's a masonry garage, uninsulated concrete floor that I can't reasonably change. It'll keep the heat in for a little longer but that's about it given the short bursts of usage.

There's a thing called thermal massing. China heaters will heat a timber shed up quickly but in a large double masonry garage, soon to be a 4 car garage with vaulted roof space - a space heater is the fastest way to get it up to temperature and to enable proper heating during freezing days.

Besides that, thermostatic control of the heater means it doesn't really matter if its oversized on paper. As soon as the space starts to get up to temperature it will knock on and off to maintain the temperature.

This is the best system I could be installing for my intended uses. Nothing to freeze during bad weather when not running. Fast to bring the space up to temperature. Runs on kerosene of which I have a 2500L oil tank for my house I can tap it into with applicable clearances and fire / shut off valves.

China heaters don't make a dent in the temperature. Electric is out as just too expensive to run. Gas is out as no piped gas here. So it's the most suitable system for my circumstances.

 

[gaz1]

So what to do - no heat(?)

It's a masonry cavity wall construction garage it'll be great. I can also have the cavities pumped with insulation this summer then get the pitched roof loft spray foamed at some point too.

dont you will regret doing so as it rots the timbers for fun and that means a new roof

 

[JOEPRO]

dont you will regret doing so as it rots the timbers for fun and that means a new roof

PIR to u/side rafters a better option maybe? Concrete tile, felt underlay unvented.

 

[gaz1]

i just fitted rolled insulation in mine and it breathes enough so wont rot compared to insulation board that dosnt breath

just wait until those timbers have rotted away if there is no roof vent up there above the insulation

as goes for the insulation its choose what you want to install board is easier but its expensive and we dont know what happens to the timbers yet whilst rockwool does protect the timbers as it does breath its just a royal pain to install it

 

[gaz1]

with the roll out insulation your best off using some planks and a roll of netting

lift the whole lot up to the rafters and roll out the netting and pin that up if you want to do it the quick way

then after is board away

 

[offthames]

The insulation won't make much difference. It's a masonry garage, uninsulated concrete floor that I can't reasonably change. It'll keep the heat in for a little longer but that's about it given the short bursts of usage.

There's a thing called thermal massing. China heaters will heat a timber shed up quickly but in a large double masonry garage, soon to be a 4 car garage with vaulted roof space - a space heater is the fastest way to get it up to temperature and to enable proper heating during freezing days.

Besides that, thermostatic control of the heater means it doesn't really matter if its oversized on paper. As soon as the space starts to get up to temperature it will knock on and off to maintain the temperature.

This is the best system I could be installing for my intended uses. Nothing to freeze during bad weather when not running. Fast to bring the space up to temperature. Runs on kerosene of which I have a 2500L oil tank for my house I can tap it into with applicable clearances and fire / shut off valves.

China heaters don't make a dent in the temperature. Electric is out as just too expensive to run. Gas is out as no piped gas here. So it's the most suitable system for my circumstances.

I use a "8kw" diesel heater in the 2 and a half car garage with large loft space and it works great. The temperature sensor is on the opposite end of the garage away from the heater. For a 4 car garage you could just use two.

Hasn't been that cold here as of late but here is an example.

 

[JOEPRO]

The only manufacturers installation diagram for the Arcotherm EC32 is as follows:



Quite a strange diagram! Sort of looks like the heater should be indoors. I guess either way is possible.

 

[gaz1]

because it uses electric its under cover is advisable

so a shed with a roof upon it would be allowed as that would protect the electrical side of it

 

[JOEPRO]

because it uses electric its under cover is advisable

so a shed with a roof upon it would be allowed as that would protect the electrical side of it

Yes that part is simple. It's always going to require cover from weather.

A: Install in a small external "dog box" and duct heated air outlet into the garage. PIV ventilation setup. Flue outside. Heater in unheated space - high risk of corrosion through time.

B: Install heater within heated space. Exhaust flue out through wall or roof. Advantage- heater safe and in heated space so no corrosion. Disadvantage is it takes up precious floor space I currently don't have but can plan for in new extension.

 

[Farside]

These always catch my eye, they have one running in the showroom at our local tractor place, probably not cheap though

https://oxdaleproducts.co.uk/product/airrex-diesel-heater-ah200i/

"No need for an exhaust pipe."
Must be running on unicorn farts or something.

 

[JOEPRO]

I use a "8kw" diesel heater in the 2 and a half car garage with large loft space and it works great. The temperature sensor is on the opposite end of the garage away from the heater. For a 4 car garage you could just use two.

Hasn't been that cold here as of late but here is an example.

View attachment 486115 View attachment 486116

Got the heater home tonight



I also ordered the Bluetooth thermostat you show data from above.

This weekend I plan to do a test run with the Arcotherm temporarily piped through a door opening and record results for a couple hours of running.

Then run the same test 24 hrs later with the China heater.

I want to see how long it takes for the arcotherm to get my garage to 20c. (Likely 20 - 30mins I'd say) and how well it's thermostat control works too.

Then compare to China run time and max temp.

Regarding fuel consumption I would also guess there won't be much difference! Aka the large heater gets the space up to temperature quickly. After that it's only maintaining the temp. The China heater runs full tilt all day and never really provides decent heat in my garage.

 

[gaz1]

if you had a analogue timeclock you could set it to come on every hr on the hr for 15 mins on each fireup

then check your temps per hr and how long does it take to cool down before another fire up is needed

https://www.amazon.co.uk/HBN-Mechanical-Immersion-Segment-Waterproof/dp/B074FQ37KX/ref=asc_df_B074FQ37KX?mcid=29be5727bdcd3872b829ee32c0509b2d&tag=googshopuk-21&linkCode=df0&hvadid=697323563897&hvpos=&hvnetw=g&hvrand=1993408864669282557&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046690&hvtargid=pla-419981988707&psc=1&gad_source=1

 

[JOEPRO]

The thermostat is just a 2 wire unit ( circa £80 - £100 too!)



I may well order a WiFi/ smart thermostat and wire it in. For now I'll use this one and see how it works.

I paid £450 for the full setup. Tested and seen it running. The accessories it came with alone are worth more than that. It's about a £1800 setup new. It is a 2014 year heater but had little to no use im told so only a couple hundred hours on it. I will still check it over and fit a new Danfoss nozzle for good measure.

 

[Bravheart]

20°C ? You working in your budgiesmugglers

 

[addjunkie]

20°C ? You working in your budgiesmugglers

Contemplation is more comfortable at 20 degrees than 5 in winter

 

[sako243]

@JOEPRO its well worth focusing on insulation and draft exclusion first. It won't be a wasted expense. Even just stopping draughts is a major step.

My workshop is 12x5m, downstairs is 3m high to the joists and then there's an office space above which is a similar size.

The roller shutter door is insulated, PVC doors and the old vents for the stable have been plugged with celotex discs. Upstairs in the office the whole roof space was insulated with 6" of celotex and the stud walls we built for the plasterboard were also insulated. Downstairs they're just rendered 18in thick stone walls. I've squirted some expanding foam above the shutter door to seal that gap as well.

If I'm downstairs in the workshop pottering about with the doors shut then even in freezing temperatures my bodyheat is enough to keep the place at a comfortable temperature. Sometimes to take the chill off I'll run a little electric heater for half an hour.

Upstairs the heater runs more often as I'm usually say at the lab bench or computer working so not generating any heat.

Its also worth keeping an eye out for people getting heat pumps on grants etc., I scored a 4 bedroom house oil fired central heating system for £180, boiler all serviced and checked regularly, 10 radiators, 2 towel rails, hot water tank, etc. from some foster carers who'd had an air source heat pump installed. Far cheaper to run than the alternatives.

 

[JOEPRO]

Got a 90 minute test run done there this evening





Very pleased with the heater, garage has never felt as warm and comfortable!

Going by the factory fuel consumption figures it would have burned 4L of red diesel. Bearing in mind the China heater has to run flat out all day and doesn't achieve near the same heat (will test it tomorrow) I am happy at that to have proper heat in there in a short space of time.