Cast Iron rad meets modern baseboard
- Thread starter trehugr
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Eric Johnson
Mod Emeritus
Heating pros will say no. They explain that because the two emitters work differently, you won't get even heating in that zone. You can pipe them into the same system, just not the same zone.
A radiator that has been used in a hot water system shouldn't contain any appreciable rust. An old steam rad, on the other hand, probably should be flushed and physically cleaned out as much as possible.
A radiator that has been used in a hot water system shouldn't contain any appreciable rust. An old steam rad, on the other hand, probably should be flushed and physically cleaned out as much as possible.
NHFarmer
Feeling the Heat
Newbie lurker opining in here.
Having done it, I say no worries. But they are different types of convectors so you need to think through the details. In particualr, baseboards hold very little water - they're quick to heat when the circulator comes on and quick to cool when it goes off. Old Cast iron, OTOH, holds a lot of water. Depending on the size, the circ will need to run for many minutes, before the cast iron is full of hot water - and it'll take > half an hour to cool once the circ stops.
So:
* In any mixed loop in my system I put the cast iron last; that way the baseboards still get hot water right away. Their opeartion is unaffected by being followed by a cast iron.
* In my place I only put the cast iron whe I wanted the delayed and maintained heat - like in bathrooms under the towel rack. The circ may come on to heat up the bedroom for half an hour at 6AM, but the bathroom & towels stay toasty till after 7:30.
* If you're concerned about hitting your boiler with all that of cold at once, bypass the cast irons with a monoflow (?) T. That'll send a fair portion of the loop water straight back to the boiler, and mix in the cold from the cast iron more slowly.
those are my 2c,
-leif
Having done it, I say no worries. But they are different types of convectors so you need to think through the details. In particualr, baseboards hold very little water - they're quick to heat when the circulator comes on and quick to cool when it goes off. Old Cast iron, OTOH, holds a lot of water. Depending on the size, the circ will need to run for many minutes, before the cast iron is full of hot water - and it'll take > half an hour to cool once the circ stops.
So:
* In any mixed loop in my system I put the cast iron last; that way the baseboards still get hot water right away. Their opeartion is unaffected by being followed by a cast iron.
* In my place I only put the cast iron whe I wanted the delayed and maintained heat - like in bathrooms under the towel rack. The circ may come on to heat up the bedroom for half an hour at 6AM, but the bathroom & towels stay toasty till after 7:30.
* If you're concerned about hitting your boiler with all that of cold at once, bypass the cast irons with a monoflow (?) T. That'll send a fair portion of the loop water straight back to the boiler, and mix in the cold from the cast iron more slowly.
those are my 2c,
-leif
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