concrete pad for oil tank evaporator

[barnbc76]

Hey guys, I'm looking to put in a concrete pad for my oil tank arch, dimensions are 28" x5'. The feet are 20"x46". We dug an area about 5.5'x4', then put in 6" of stone. This will not likely be the final resting place for it (hopefully I'll be able to move it into one of our outbuildings. So I was thinking of making 2 small pads, 16x32". Is this too small? If should we just go the extra mile and make it one big one?

[MISugarDaddy]

Personally I would pour one slab so that it is not likely to shift and cause your evaporator to be unlevel. If you don't want to spend the money for one slab or figure you will be moving it soon, you might consider just placing it on four concrete blocks. You can purchase solid concrete blocks that could sit on your stones you have already prepared. If you are thinking of using the two smaller slabs in its future resting place, it may be a lot of work to try to get them level when you move them, and depending on their thickness, they may not be to light to work with.
Gary

[NhShaun]

If you are not planning to keep it there for a long time I wouldn't pour one big slab. Unless I had some heavy equipment to move it. wouldn't hurt to put a couple rebar loops in the top or side for future lifting / dragging.. Kind of like a septic cover. Using some smaller temporary blocks will get you by, would help to have adjustable feet in case it shifts a bit.

[minehart gap]

I have moved 4’x6’x4” concrete slabs with my small skid loader before. Just make sure that there is plenty of rebar in it. Also, if you make the base for where you are going to move it to with limestone sand, it will level up somewhat easily. Spend a little extra time when you pour it to get the rebar up off of the stone and have plastic down before you pour so that the stone doesn’t get into the concrete.

[maple flats]

For temporary I'd likely just use precast slabs made like sidewalk sections. Before you set them, tamp the crushed stone well, and some stone dust in the mix works well. As said above, make the legs adjustable, Check out something like this: https://www.newegg.com/Product/Product.aspx?Item=9SIA5KG5T74603&ignorebbr=1&nm_mc=KNC-GoogleMKP-PC&cm_mmc=KNC-GoogleMKP-PC-_-pla-_-AT+-+Heating%2C+Ventilation+%26+Air+Conditioning-_-9SIA5KG5T74603&gclid=CjwKCAiA3o7RBRBfEiwAZMtSCTuwNf0EeTHUo637yu7p 1um_yAX8QU6mEk-eJiR9vjMP4aLy2lysRhoCvD8QAvD_BwE&gclsrc=aw.ds
Various vendors sell them. You can likely find them a Home Depot or Lowes and not pay frt.
Then when you go with your final design/evaporator go below frost line, pour a pad or 2 pads, Lay blocks with morter on the pad(s) and then pour a floor on top. I set mine 4.5' deep, and I poured 2 pads, at the time I had a 2x6, but I poured the main footer large enough to accommodate any from 2x6 up to 3x10, it was 4' x 6' x 8", then the back legs rest on a smaller slab that is 4' x 16" x8". Many don't go below frost line, but it helps keep a rig from frost heaving. When I poured my floor later, I have the evaporator slab isolated using expansion joint. That way, if the floating pad shifts it will not take the evaporator with it.