Radiator radiant heat help

Ghynes440

we just moved into an old 1890’s home and we realized some of the radiators do not work in the back of the house. I have a thermal camera and noticed this in the one radiator, it’s hot on top but cold on bottom. For some reason the shut off valve is connected to the top? But all the other radiators are connected on the bottom.

what would cause hot on top but cold on bottom?

EdTheHeaterMan

Gravity. Hotter water is less dense and therefore lighter than colder water. Back when homes were heated with coal boilers, the systems were installed without pumps to move the water. the hot water in the basement coal boiler was lighter than the colder water in the radiators. so the heavy cold water would fall down the return pipes forcing the lighter hot water to go up the supply pipes.

Many of those systems are still in use however the new replacement boilers are a lot smaller and require a pump to move the water thru the system. If the pump and near boiler piping is not assembled correctly you can get uneven heating across the system. We would need to know more about your system to determine the proper fix. Can you take a picture of the near boiler piping from several directions? include the pipes aand boiler from the floor to the ceiling.

Ghynes440

Hi Ed,

Thank you for that! Yes absolutely, I will take pictures as soon as I get home from work and post them

Ghynes440

here are photos of the setup

delcrossv

Interesting. Where's the compression/expansion tank? Attic?

Ghynes440

https://forum.heatinghelp.com/discussion/comment/1842713#Comment_1842713

it’s to the left out of sight right above the oil tank

techforlife

I am guessing you are using the coil and a booster tank for hot water? With the circ. short cycling from the low limit reverse on such a high mass system, you are likely not getting enough continuous flow to heat that rad. evenly before the Tstat satisfies.

Ghynes440

https://forum.heatinghelp.com/discussion/comment/1842779#Comment_1842779

I’m going to be honest, I’m not sure what most of that means! 😂 heating with radiators is new to me, so I’m still learning. They have the hot water heater hooked up weird, where the boiler heats up the water and sends it to the water heater for “storage” I doubt the water heater rarely kicks on.

How would I fix the short cycling? I’m thinking about possibly converting to natural gas this year because there is a gas main right out front.

pecmsg

https://www.heatinghelp.com/store/detail/classic-hydronics-how-to-get-the-most-from-those-older-hot-water-heating-systems/

https://www.heatinghelp.com/store/detail/pumping-away-and-other-really-cool-piping-options-for-hydronic-systems/

techforlife

With all due respect, I have outlined for you the issues involved in simple but professional terms. Now that I have read your reply, it has become apparent that you need a pro.

techforlife

BTW. Converting to gas will not alleviate issues. Changing fuels only changes the source of the BTUs.

hot_rod

If you are planning to change to gas, a modulating condensing type boiler would thrive in a system like yours. I would head in that direction