String Radiators Together

erich_4

I have 2 12 section units. This is a steam system in NJ.

erich_4

String Radiators Together

Can you string 2 cast iron radiators together?

I have access to 2 of these http://www.governaleindustries.com/govfree.cfm

I need to heat a room that is 18x12. Thanks.

Brad White_203

Yes you can

There are a number of ways to do so. I have seen them piped all different ways, top-in/bottom out, all bottom-connected, bottom-in/top out.

The "all bottom connected" seems to be most common, with the first connection in the top of the first radiator and out the bottom of the last- must have been a gravity HW throw-back, I suppose. The pipes were pretty large.

I have also seen pairs with both top and bottom connections between the two radiators. Unions are usually used and in the old days, LH/RH couplings.

Given the low velocities and pressure drops, I have to wonder if it makes a difference which way you go.

Certainly you should take into account that the last radiators will see cooler water so your flow rate should reflect that, as well as your average water temperature. If you are connecting this to an existing system, know the operating parameters/temperatures of the hot water system you are connecting to.

I do not know in what climate/location the project is, nor the heat loss, so do calculate that first. I know that you say you have access to these, meaning probably specific radiators. But it is good to double-check before you install them of course!

Brad White_203

Important information

What I described is for hot water.

Yes, it can be done but the overall pitch back to the inlet side has to be taken into account and the connections between the two need to be short. Also, you want to connect the two tappings facing each other, both high and low between them, so that it acts as one radiator. The bottom pipe connection at least wants to be the full size of the bottom tappings. If you reduce, with any bushing, you will create a "shelf" or "dam" where returning condensate will sit.

An alternative means would be to supply between the two and pipe to a radiator on each side. If so done, you might also put a vent bushing (or provisions for one) on the center supply pipe if this is the end of a major run. That might speed things up a bit if this is remote.