Car radiator inlet/outlet connections

[Red Squirrel]

What type of connections do car radiators use for hoses, and is it standard? Is it possible to adapt that to regular house plumbing, ex: 1/2 pex or copper, or NPT etc. Like is that something I'd be able to find the proper fittings for or would I need to fabricoble something myself? The system won't be under any serious pressure so I think hose clamps will work ok.

Looking at using some car radiators for a HVAC related project, just going to see if I can find some for cheap, I don't have any on hand at this point I just want to make sure that I can actually properly adapt them in first place.

Also will they handle glycol/water mixture fine? I would assume so as car coolant is probably similar or even the same.

 

[EXCellR8]

Pretty sure most OE and aftermarket radiators will handle glycol without issue, but I'd make sure to check with the manufacturer just in case.

 

[pcgeek11]

I don't think they are all a universal diameter, but close.

And yes they are resistant to water glycol mixture which is basically antifreeze.

 

[deadlyapp]

Most car radiators will have aluminum fins and typically plastic or steel end caps. All should handle a water-glycol mix fine - just make sure you try to use distilled water. If you're buying one from a junk yard I'd do a couple of good flushes with it to get any junk out of it before putting it into a new system.

Diameter isn't going to be universal, but generally between 1-2" and they're just straight barbed fittings. You can get plenty of adaptors if you want to go from barb to something else. You probably won't be able to find any cut-sheets on the radiators, so it will be impossible to know the heat rejection capacity of the cooler, the pressure drop, etc, which makes putting it into a system worrisome in my opinion.

 

[Red Squirrel]

Good to know about adaptors, guess it's something I could get at an automotive shop.

Not too worried about specs, it will be better than anything I would build myself (ex: using a bunch of copper in a coil or something).

Some rads appear to have a bunch of other connections too, can those be ignored or do they need to be capped? Guessing they are auxiliary ports for the heater etc.

 

[EXCellR8]

Some radiators have integrated oil coolers but I feel that would be fairly obvious just by looking it over. They aren't cheap, that I know for sure.

 

[NutBucket]

They're cheap when you source them at the junkyard

 

[herm0016]

most of the larger rads are going to have connections for a transmission fluid circuit. it helps warm up the transmission and cools it when it does get hot.

solar heating the shed?

 

[Red Squirrel]

They're cheap when you source them at the junkyard

Yep and ebay etc too. About $100 range for one. Someone on FB is parting out Silverado parts off a bunch of trucks so hoping to get two for decent price.

Want to see if I can use it to heat the garage in winter. Will have backup baseboard heat. Essentially a air to water to air heat exchanger, not going to be the most efficient, but I think it should work to at least keep it 5-10 degrees in there. Enough to work in.

Do want to do the shed too eventually but I'd just do electric with a sand/concrete thermal mass. Need to figure out how to automate snow removal first though as it's hard to keep up with that manually. Would be nice to store things like hose, sprinklers etc without them bursting over the winter.

 

[deadlyapp]

The radiators with multiple port have an integrated transmission or oil cooler built in. You can simply not use it if you want and you accidentally get one.

I'm confused by your idea though. You want to ...what, use two radiators, one that you blow hot air over to heat up the water, and the other that you blow cold air over to warm up the air? Why don't you simply duct the warm air into the space you want to warm?

Or are you thinking about piping off your hot water heater and running a pump to circulate warm water through the radiator and blowing cold air over the radiator to warm up the air?

 

[Red Squirrel]

Air ducting requires two 5ish inch holes in concrete while pex will require two 1/2" holes. Much easier and less rebar to go through or none at all if I'm lucky with my holes. That and I'm not sucking in saw dust and possibly other stuff through my house. Keeps it a closed system.

If my two rad idea does not work then I'll eventually add a boiler to the equation or stick one of the rads in the furnace return or air supply. Lots of different options to play with to heat the water. Eventually I'll have the server room setup to recirculate the air through the radiator and use that to heat the garage, extra indoor heat will be added to server room as needed to keep it from getting too cold. The whole system will be automated with servos/dampers to keep both the server room and garage at the temp I want.

 

[deadlyapp]

So I was correct, you want to blow warm air, somewhere in your house to heat up water in a closed system, and then move it to another room.

I'm telling you, the amount of additional cost and the terrible efficiency you're looking at makes this absolutely the most idiotic engineering solution I've ever heard.

You're talking about probably a pretty decent power pump to overcome all the system resistance and losses. I have no idea what that flowrate and pressure needs to be, which lends itself to another problem - sizing the pump. You need to size the fans for the radiators, enough flow and pressure to get across the fins but not too powerful to the point that you don't get any heat transfer.

Finally, the other big hurdle is simply the temperature differences. Lets say your internal house temp is 22 deg C, you blow that air across water that is...5 deg C. You probably get a water temp around 15 deg C if you're lucky. Then you take that 15 deg C water and blow 0 deg C air and maybe get 7-8 deg C air. As the final room warms up, the heat transfer gets worse. These are just rules of thumb and not actual calculations, but a 7-10 deg C temp delta would be terrific. For reference, a car radiator in a car has an inlet temp around 190 deg F and outlet temp somewhere between 170-180 deg F with an ambient air temp sized around 80-100 deg F.

 

[Red Squirrel]

The goal is just to try to keep the garage above freezing. The system will turn on/off as needed. When I need more heat I'll just turn on the baseboard heaters higher a few hours ahead of time. It's going to be a workshop so don't need it more than like 10-15 degrees in there to be comfortable once I start working. Heck even at 5 degrees I can still work in there if I put long sleeves.

The water does not really need to move fast, just going to use a circulator pump like you would for radiant floor heat that uses 100's of feet of pex line. From what I understand car radiators essentially split the inlet into many "pipes" then recombine them. Technically the static pressure should be less than a radiant floor heat system.

Ideally with the room being very well insulated the heat loss rate will be lower than the heat gain rate, and I'll be able to maintain a comfortable temp. Obviously the furnace in the house technically has to work slightly harder because I'm taking heat away from the house but the furnace is more efficient than small gas heaters you can get for garages, as those tend to be low efficiency.

May eventually get a tankless water heater, some of them have a boiler inlet/outlet that is separate from the potable water, so I'd probably use that if the system does not work well enough as I plan it since it would get the water much hotter.

 

[deadlyapp]

A gas heater is probably a thousand times more efficient than the system you envision when you consider all the electrical loads of the fans and pump and simple heat transfer efficiency.

You're taking your 90% furnace efficiency + the heat exchanger efficiency x 2 + pump efficiency vs the probably 80% gas heater efficiency which will already have the capability to force the air around the room. You just turn it on and off as necessary.

 

[dave_the_nerd]

Yeah... they make heaters specifically for this. They're under $100.

More options if you have 220v, but even a dinky 1200w space heater will keep an insulated garage pretty comfortable if you let it run a bit.

Have you insulated your garage already, by the way?

 

[Red Squirrel]

Not yet but it will be insulated. Lot of stuff needs to be done first like bringing in electrical, data, etc. The space heater will be the last resort, hydro is super expensive here. The cheap gas heaters also require to run a gas line. Got an estimate to run a gas line somewhere else a while back and it was a few grand. Will probably be easily 5 grand to run it all the way to the garage. Those small heaters are also super inefficient, they suck lot of air outside and rely on the room being leaky for combustion air.

 

[lxskllr]

Aren't you demoing a chimney that has access in the garage? You could put a little wood stove in there to keep it warm.

 

[Red Squirrel]

Was thinking that but that's like a 5 grand ordeal once all is said and done (proper chimney, Wett certification etc). I had looked into it as I do like the idea of a wood stove. Increases insurance costs etc too though. If I put a wood stove I'd probably want it in the house, may as well heat the house with it, then I'd do hot water to heat the garage.

Basically I'm trying to keep this cheap and the heat will be technically "free" by using house heat. If I really want to go to town I could put the inside rad right inside the furnace plenum or one of the big trunk lines too. But think ultimately the goal will be to tie it into the hvac system of the server room once I design that. May as well make use of that excess heat. It's not much mind you, like 500w maybe. It's kind of a chicken and egg situation though as I need my garage to be done so I can have a work area to even build that hvac unit, but for the time being I'll run on the electric rads. Only really need 5C in there to work comfortably and for tools etc to not rust, just need to put on long sleeves. My A/C unit also has a dehumidify and heat function, so I can probably run that too, though I don't imagine it will work well in -40's. On those days the electric rads will probably need to kick on more.

Also kind of debating on doing radiant heat and I have the opportunity to add the lines before they add 3 inches of concrete but I'm just a bit worried if the lines freeze for any reason it would break up the slab. If I use glycol as originally planned, that's a whole other ordeal, was reading up on that and you need to change it every year since it starts to go bad. So with the rads think I will do just water and just have some fail safes to make sure it never freezes. If it does, I lose a rad, not a whole floor.

 

[Micrornd]

Just throw a bunch of halogen lights in there, that'll warm it up.

 

[mindless1]

Electricity can't be that expensive, not to merely heat a well insulated room to 5C. What if you just put the server room contents there? Build an enclosure, put an intake filter on it and a fan exhaust.

 

[BoomerD]

Put my 65" Panasonic plasma tv in there...that thing would turn the room into a sauna...

 

[mindless1]

It's kind of a chicken and egg situation

I never thought about the animal solution. Fill the room with Siberian Huskies.

 

[Red Squirrel]

Electricity can't be that expensive, not to merely heat a well insulated room to 5C. What if you just put the server room contents there? Build an enclosure, put an intake filter on it and a fan exhaust.

It's already small enough as is don't want to take up more space with server racks. Will need to have a spot for hvac unit but think I will build it so it can be mounted on the ceiling. My portable A/C unit will be setup permanently as part of that hvac unit too. The server heat will sorta be used through the water rad system though. Air from hot aisle will go through indoor rad and go in crawlspace. Cold aisle will be fed from other end of crawlspace. The house heat will of course keep the crawlspace at a reasonable temp too. Servers alone are only like 400w (actually probably more like 800w with mining rig) so that's a drop in the bucket to actually heat anything, but it's something. There will be various dampers and such too throughout the whole system.

Eventually if I get a tankless water heater then I will use that to add heat into the water loop after it goes through server room. Main thing is to just get the loop in place then I can experiment from there.

 

[dave_the_nerd]

It's already small enough as is don't want to take up more space with server racks. Will need to have a spot for hvac unit but think I will build it so it can be mounted on the ceiling. My portable A/C unit will be setup permanently as part of that hvac unit too. The server heat will sorta be used through the water rad system though. Air from hot aisle will go through indoor rad and go in crawlspace. Cold aisle will be fed from other end of crawlspace. The house heat will of course keep the crawlspace at a reasonable temp too. Servers alone are only like 400w (actually probably more like 800w with mining rig) so that's a drop in the bucket to actually heat anything, but it's something. There will be various dampers and such too throughout the whole system.

Eventually if I get a tankless water heater then I will use that to add heat into the water loop after it goes through server room. Main thing is to just get the loop in place then I can experiment from there.

Actually, once the garage is insulated, 800w is a nontrivial amount of heat. Belieeeeve me. Woof.

 

[JEDIYoda]

I can remember when we were traveling through this solar system we had a major trilythium leak in the Dilythium rediayor array!
It was night on planet earth so we beamed into an Auto Zone store and we were pleasantly surprised to find that they had an almost matching part for our array!!
We beamed back up to our craft and made the repairs!! We were off and running!!