baseboards hot but thermostat disconnected

bentz69

Hello everyone.

I will try my best to explain the situation but please bear with me since I really dont know much about boilers. If I leave any important information out then please tell me.

To start, I moved into a new home over this past summer. I have a older Burnham boiler that uses oil, has 3 heating zones (basement, 1st floor, 2nd floor) and heats the hot water. I turned on the heat in every zone about a month ago to make sure all the baseboards in the house were functional. During this time, I heard a lot of gurgling coming from a few off the baseboards. I figured there was a lot of the air in the pipes so I needed to the bleed the system. Fast forward to several days ago.

I turned on the heat in each zone at the same time and waited about 20 minutes to get everything hot. I started with the basement zone, then the 1st floor and finally the 2nd floor. I connected my hose to the drain for the basement zone, closed the valve before the pump then opened the drain valve to let the water out. For each zone I needed to open the fill valve to allow more pressure. Each zone was done the same way. byt BTW, there are no zone valves on this system. There was a lot of brown/black water and substantial amount of air coming out the of the hose for each heating zone.

When I was done bleeding each zone, I noticed the water pressure was almost 30psi. Since the hose was still attached to 2nd foor zone, I opened the valve to allow some water out to lower the pressure and I set the water pressure to the same 21psi that is was set to before I bled the system.

So heres my problem that I never noticed before. The second floor has 4 bedrooms and 2 bathrooms. The 2 baseboards in my bedroom and the 1 baseboard in a seperate bedroom are constantly warm/hot no matter what. All the other baseboards are cold. At first, I thought the thermostat went bad so I completely removed it from the wall. That didnt work and those same baseboards are still warm. Then I figured something happened to the pump. I connected the multimeter to the pump but its not pulling any volts. So its definitly not running. The only way I can stop these baseboards from giving off heat is to close the valve on the rear of the boiler that goes to the second floor.

I dont understand how these baseboards can be giving off heat if there is no thermostat connected and the pump is not running. What is pulling the water through the pipes?

Thanks for the help

Grallert

You have three zones and no zone valves correct? in that case you have three circulators correct? Because older system circulators have no way to prevent convective movement of the warm/hot water from the boiler to the cooler water of the system a flow check of some sort would have been install on each heating zone to stop that convective movement. These can get stuck on an open or partially open position. Depending on the type of check installed, these can often be freed up with a couple of light raps on the body of the check. Or you can replace the circulator with an updated version which has a built in flow check. Then open the existing check valve thereby essentially removing it from the system.

bentz69

Yes there are 3 zones and no zone valves visible anywhere that I can see. Yes there are three circulator pumps as well.

Where would a flow check valve typically be located? I don't see anything like that. Like I said, the only way to stop the flow of hot water is too physically turn the handle off for each zone on the rear of the boiler. I'm not sure but I have to assume that this boiler is from when the house was built in the 1980s. Is it also possible that a flow check valve wasn't installed in this old system?

The pump for the second floor was replaced a few years ago with a Armstrong astro 230ci. Do you know if there is check valve built into this type of pump?

I spoke to the previous homeowner and he said he has never noticed any heat coming out of the baseboards when the thermostats are off. Is it possible that because there was so much air in the system that the water was unable to rise up to these baseboards?

neilc

are your links working ?
I'm not seeing pictures, just some "interesting" advertising

Grallert

bentz69 said:

Yes there are 3 zones and no zone valves visible anywhere that I can see. Yes there are three circulator pumps as well.



Where would a flow check valve typically be located? I don't see anything like that. Like I said, the only way to stop the flow of hot water is too physically turn the handle off for each zone on the rear of the boiler. I'm not sure but I have to assume that this boiler is from when the house was built in the 1980s. Is it also possible that a flow check valve wasn't installed in this old system?



The pump for the second floor was replaced a few years ago with a Armstrong astro 230ci. Do you know if there is check valve built into this type of pump?



I spoke to the previous homeowner and he said he has never noticed any heat coming out of the baseboards when the thermostats are off. Is it possible that because there was so much air in the system that the water was unable to rise up to these baseboards?

Pictures of your system would help. I'm going to guess the the circ pumps are on the returns of each zone, often the case with older systems. The flow checks are going to be on the supplies. In other works to heat pipes going to the rooms. There are a few different types, some made of iron some of brass.
Don't know about the Armstrong 230... Your pictures didn't come threw.

bentz69

bentz69

Its now my understanding that there is a flow check valve installed but there is only one and it is on the basement zone. It is in the picture that has the 3 supply pipes labeled. I cant find any anymore of these valves anywhere in the boiler room

Today was even colder and now I notice that the 1st floor is also experiencing a baseboard or 2 that was getting warm even though the thermostat was off. The basement does not have his issue.

So since I cant find any other flow valves that I suppose that tells me they are not installed

JUGHNE

Is that 3/4" copper coming out of the top of the boiler feeding all 3 zones? The pressure relief valve would be piped in 3/4" to the floor for dumping, is it that size?

bentz69

JUGHNE said:

Is that 3/4" copper coming out of the top of the boiler feeding all 3 zones? The pressure relief valve would be piped in 3/4" to the floor for dumping, is it that size?

Yes that copper coming out the top of the boiler is feeding all 3 zones. The pressure relief valve is is located in the circle in this picture. When I was bleeding the last zone (2nd floor) the pressure relief valve did pop and dumped maybe 2 gallons of water into a bucket that I placed under the dump pipe. Some water came out of the valve also.