Shop temperature control

Batmanacw said:
Worst case I'm looking at $300 a year to heat my shop with zero moisture issues. Probably not that much. Most suggestions I've received involve way more than that to install something better and a 6 to 10 year payback.

I could easily run my big buddy heater into my shop and run it on high to warm my shop up quickly. I simply don't want the moisture.

Try to remember this is a 12 x 20 ft space. It doesn't take much to heat. I'm not heating a house.

$300 a year isn't a heavy burden. Definitely not worth $2000 in debt to cut that in half.
Click to expand...
Not certain what you humidity looks like but I am just out west of Houston and I have found that it is much easier to keep my shop temperature comfortable if I run my dehumidifier 24/7.
 
verbotenwhisky said:
Not certain what you humidity looks like but I am just out west of Houston and I have found that it is much easier to keep my shop temperature comfortable if I run my dehumidifier 24/7.
Click to expand...
Running a dehumidifier would cost more than my entire heating and cooling budget combined. My shop is bone dry in the winter and my air conditioner keeps it dry in the summer.
 
RJSakowski said:
Heat pumps don't fare well in Wisconsin winters. They are at their lowest efficiency when you need them the most. Their efficiency is only slightly above that of resistance heating and their throughput is drastically reduced. I have a mini split which I use mainly for cooling in summer. I generally turn the unit off from late fall until mid May. I am heating/cooling a well insulated attic space and generally get enough heat from the house below to keep the room at 60º. If I need a quick warmup, I have 4 KW worth of baseboard resistance heat which will usually warm the room in sbout 20 minutes.

Using a heat pump with a geothermal heat source is a different matter. They can be very efficient in Wisconsin where ground temperatures are around 50º -54º . Unfortunately, the upfront cost can be prohibitive for a modest need. I would expect a very long ROI.
Click to expand...
My experience says otherwise. We used two minisplits to heat our old farmhouse through October and November and often most of December also, before starting to burn wood in our furnace in the basement. They heated down to 15 below, before efficiency dropped off, unlike cheaper units. They are Fujitsu 15K "Extreme Low Temperature Heating" models and provided over 4.5 kW of heat for every 1 kW of energy used.
 
By stopping the cold/heat from getting in is the cheapest way to go year round.
Can you add insulation to the exterior of the walls, ceiling and around the floor to below the ground? Try to keep the interior warmer by reduce heat lost. Look for faced foam board. Some are available with pre installed siding like material.
Also with a concrete slab by insulating what is visible to the outside and into the ground can help maintain the temperatures inside closer to desired.
Pierre
 
Last edited:
pdentrem said:
By stopping the cold/heat from getting in is the cheapest way to go year round.
Can you add insulation to the exterior of the walls, ceiling and around the floor to below the ground? Try to keep the interior warmer by reduce heat lost. Look for faced foam board. Some are available with pre installed siding like material.
Also with a concrete slab by insulating what is visible to the outside and into the ground can help maintain the temperatures inside closer to desired.
Pierre
Click to expand...
I'm very well insulated but it could always be better. If I covered the rest of the floor in mats it would be warmer feeling. My ceiling is r19 with a pitch roof above. Right now it's pushing 90⁰ and it will br 70⁰ in the shop tomorrow morning. Nothing running.
 
WisJim said:
My experience says otherwise. We used two minisplits to heat our old farmhouse through October and November and often most of December also, before starting to burn wood in our furnace in the basement. They heated down to 15 below, before efficiency dropped off, unlike cheaper units. They are Fujitsu 15K "Extreme Low Temperature Heating" models and provided over 4.5 kW of heat for every 1 kW of energy used.
Click to expand...
Interesting. I have an 18K MrCool DIY mini split. It specifies a heat mode range down to +5ºF (-15ºC). A COP of 4.5 is impressive. Most heat pumps have a COP of around 2 at -15ºF. At a COP of 2, the heating costs exceed those of a natural gas or propane heater., not to mention my costs for heating with wood.

Aside from the unit efficiency is the drop in output at lower outside temperatures. An 18K unit operating at a 60ºF outside temperature will only output 9K Btu at 0ºF. This as compared to my baseboard resistance heaters outputting 14K Btu. For my small space, this is probably sufficient.

I heat with a wood furnace in the basement and my chimney runs up the middle of my attic space. The heat from the well insulated chimney is sufficient to keep the attic space close to 60ºF on all but the coldest winter days. I knew the the MrCool mini split wasn't the most efficient available nut I chose the MrCool mini split because of the precharged system. Although I have the equipment and knowledge to charge an HVAC system, the thought of doing so on a rooftop didn't appeal to me.
 
One relatively inexpensive fix to reduce heating costs my brother in northern Wisconsin did was to insulate the perimeter of the foundation down to 4 ft. with 2" closed cell styrofoam board. Ground temperatures up there are around 40ºF and that effectively turns the floor slab into a large thermal mass.
 
This one time my little basement shop is an advantage: while the inside unit for my heat pump takes up valuable space, minor air leakage plus a half-closed supply vent keeps the temperature between 65F - 68F year round at minimal added cost. I do run a dehumidifier on auto to keep the humidity under control, but once I replace the electric water heater (it’s 15+ years old) with an inverter heat pump water heater, I’ll be able to get rid of the dehumidifier plus save energy costs.
 
RJSakowski said:
One relatively inexpensive fix to reduce heating costs my brother in northern Wisconsin did was to insulate the perimeter of the foundation down to 4 ft. with 2" closed cell styrofoam board. Ground temperatures up there are around 40ºF and that effectively turns the floor slab into a large thermal mass.
Click to expand...
inexpensive? digging out to 4 feet is inexpensive???
 
You must log in or register to reply here.
Back
Top