2nd floor heating problem

[rh71]

We have baseboard heat with a gas boiler in the basement of our 2-story 2700sf home. It seems like our 2nd floor is hardly getting warm despite the thermostat being set to 67 for over 2 hrs but it was still registering as 61F up there. The baseboards only feel warm to the touch but don't seem to be radiating enough heat to do much. 1st floor is working fine and hit the 67F target (separate zone) until bedtime when it automatically lowers.

The attic isn't too well insulated but it and the 2nd floor are relatively new construction with Andersen windows throughout the 2nd floor. It's under 15F today and I get that it might have a harder time but not gaining any heat now or any rise in temp for over 4 hrs seems like a problem. Thermostat on 2nd floor is definitely showing heat is on and running. But the boiler (4 years old) in the basement doesn't continuously run for some reason, maybe an efficiency / cycle thing that I've come to accept over the years.

I used to hear running water in these baseboard pipes which meant water flow but haven't in quite a long time. Like I said, the baseboard is still warm but not sufficiently effective in all 5 rooms.

Does it prioritize the 1st floor or something? What would cause this scenario? Is the boiler simply insufficient for our needs when this cold? It is rated at 85% efficiency. http://www.usboiler.net/product/esc-gas-fired-water-boiler.html. Figure these things would at least continuously run to try to make the temp even if it never reaches it.

Even when it does run, I can't tell if it's doing our water tank or the baseboard heat up here.

 

[jmagg]

Sounds like an out of level or malfunctioning thermostat or battery. It doesnt take much out of level to skew the temp that much. If you turn the upstairs thermostat up, does it raise the temp accordingly but 6 degrees low?

 

[NetWareHead]

What kind of boiler (brand and model)?

If you used to hear running water in the second floor heating loop but no longer do, you may have air in the line. If so you need a purge.

Compare the first and second floor circulators when running. Set second floor thermostat to off and only call for heat from first floor. Reverse the floors and call for heat from second floor. Air in the line sounds distinctive.

 

[boomerang]

Thoughts from someone that has minimal knowledge of hot water heating systems. (Me)

I used to hear running water in these baseboard pipes which meant water flow but haven't in quite a long time.

This makes me think that the circulator pump is not running for the upper floor.

But the boiler (4 years old) in the basement doesn't continuously run for some reason, maybe an efficiency / cycle thing that I've come to accept over the years.

Or, a safety function that is turning off the boiler because with no circulation, there is no way to dissipate the heat.

 

[monkeydelmagico]

This makes me think that the circulator pump is not running for the upper floor.

Same thought plus one: air bound. Check the Air Bleeder valve. Sometimes they get crusted up and need a little manual cleaning/purging

https://inspectapedia.com/heat/Air_Bleeder_Valves.php

 

[Humpy]

Check that the zone valve is open or the zone pump is running. Most have indicator lights or you can touch a pump and feel if it's running. You can also (cautiously) grab pipes in the utility room and tell by their temperature differences which ones have hot water flow and which don't.

Most systems are set to prioritize domestic hot water, so you can turn that off to see if the heat comes on.

If you aren't already, now is a good time to familiarize yourself with the maze of pipes and valves in your utility room. It's all pretty simple once you begin to understand it.

If it's colder than normal it is also entirely possible that you are below the design temperature of the system. My system will heat up to 68 when it is 15 outside. Any colder, or if it's really windy, I have to put on a sweater or start drinking.

 

[rh71]

Attached a pic of our setup. It's 1 circulator and 5 zone valves (4 zones + water heater), one zone (far right) being the 2nd floor. Just now when I called for heat (set to 80-90F when it was only at 61F), the boiler ran for about 5 minutes then stopped, then started again minutes later. All the while the first floor still hasn't reached temp either, and it's continuously short-cycling). There is hot water (really hot) running through the boiler pipe going up toward the 2nd floor, so zone valve is good there. I went up there and same as last night - it's not hot enough to do much heating. My hot water tank is set to 125F if that matters. Will raising that temp do anything to heat the upstairs better? EPA recommends 120F.

Here's where it also gets confusing. I then turn off the first floor thermostats and the boiler doesn't try to come on anymore, even though the 2nd floor is still requesting heat. Then why did hot water come up to the 2nd floor in the first place if it's a faulty 2nd floor thermostat? I guess I'll try swapping the thermostat from the basement that's never used.

We were recommended this setup by the plumbing company who put this in 4 years ago. They said the 1 circulator setup is more modern and efficient. The readout is usually swapping between 7 watts or 0 GPM (as seen in pic).

 

[boomerang]

So, if you turn the thermostat up for the lower level the boiler will continue to run until the that temperature is satisfied? No short cycling?

If so, I'd say it's the thermostat or the zone valve. I am making the assumption that that zone is not full of trapped air. But when you say that the boiler has been short cycling for as long as you can remember, I'm thinking you should have had the outfit that installed it out a long while back when it was warranty work.

There is no shame in having the professionals out. We all have our limitations. I'm pretty handy but I'd be making the call.

 

[herm0016]

you got recommended that setup because its easy and cheaper to install, not because its more modern and efficient. call someone, or read the manual that came with your boiler and see if they cut any other corners.

my wife's parents just paid a boatload to get their boiler completely re-plumbed with 2 pumps and strainers and reserve tanks because the last guy used the single pump setup and wrong size piping among other things.

call a professional, and not the lowest bidder.

 

[Humpy]

Are the fins in the upstairs baseboard clean?

 

[rh71]

I removed the 2nd floor thermostat and am testing by twisting the red and white wires together. Turned the boiler back on and it ran for about 5 minutes and stopped and hasn't come back on. I assume it *should* be running until I undo the wires.

Yes the fins are clean as new (2nd floor is only 7 years old). I touch the actual pipe behind the baseboard and it's only warm, just not enough to radiate enough heat for the rooms. Curious, is it possible for the circulator to work (running hot water upstairs) independent of the boiler running (since that's not on currently)?

So, if you turn the thermostat up for the lower level the boiler will continue to run until the that temperature is satisfied? No short cycling?

1st floor was short-cycling even without reaching the temp, but it would eventually as we could feel the heat and the number on the thermostat was rising by the hour. 2nd floor (while they were on simultaneously) would have never reached the temp and now doesn't even run, wires only. Doesn't explain why hot water was sent upstairs then. Air in the system the only explanation left? The other issue - boiler still doesn't want to run continuously when requested.

EDIT> boiler came back on after 10 minutes idle... and off again after 5 more minutes. Can't tell if it's for the water tank, the boiler heat exchanger (so I'm reading), or the 2nd floor (pipes still hot in basement and only warm upstairs).

 

[monkeydelmagico]

If so, I'd say it's the thermostat or the zone valve. .

I am betting zone valve. Easy to tell. If the pipe temp on the boiler side is HOT but after the zone valve it's not bingo.

Some zone valves have a manual over ride.

 

[rh71]

^ pipe past the zone valve going to 2nd floor is hot. Pipes upstairs are warm.

 

[hdfxst]

If the pipe is hot after the zone valve but only warm upstairs you have air in the system.And the boiler is only going to run until the water hits a set temp,the circulator pump will run until the thermostat is satisfied

 

[rh71]

If the pipe is hot after the zone valve but only warm upstairs you have air in the system.And the boiler is only going to run until the water hits a set temp,the circulator pump will run until the thermostat is satisfied

Does the circulator run silently and independent of the boiler? Seems like yes. I had assumed the boiler has to be on for heat to be generated/pushed upstairs.

 

[hdfxst]

The boiler has an aquastat that controls the temp of the water,so when it hits that temp(180-200 degrees)it shuts off,so it's always cycling.The circulator will run nonstop until the room reaches the temp you set at the thermostat.

 

[boomerang]

Rereading your first post, the second floor is an addition, correct? Was the boiler resized to cover the additional square footage?

What's also going through my head is how long it takes for hot water to reach the faucet the farthest from the HWH in a ranch home. If the zone for the lower level is running and the boiler is undersized combined with the distance the hot water has to travel to the upper level then combine all that with really low temps...

Is this the first bout of weather this cold since the addition?

 

[monkeydelmagico]

Rereading your first post, the second floor is an addition, correct? Was the boiler resized to cover the additional square footage?

What's also going through my head is how long it takes for hot water to reach the faucet the farthest from the HWH in a ranch home. If the zone for the lower level is running and the boiler is undersized combined with the distance the hot water has to travel to the upper level then combine all that with really low temps...

Is this the first bout of weather this cold since the addition?

If that was the case the boiler would run alot. OP is stating that it cycles with long pauses. This seems to indicate that only a few of the zones are functioning correctly. As mentioned previously by several posters we have not ruled out air in the system yet. OP doesn't seem to understand or is able to tell us if the air bleeders are functional for the zone(s) in question.

 

[NetWareHead]

Op the boiler won't run continuously. The boiler stops firing when the water hits the high limit, probably 180 degrees. The circulators will stay on (and zone valve stay open) though until the call for heat from any thermostat ends. When the water falls below a certain temp during a call for heat, the flames come on again.

Doesn't sound like the boiler is the problem being undersized. Op mentioned the second floor baseboards being only warm. Undersized boilers fire and run constantly and the baseboards get to normal operating temperatures. It is the structure that soaks up all the heat delivered and never becomes warm

The fact the first floor is satisfied and baseboards get hot shows the boiler is not the problem. Nor is it the circulator, you only have one and other zones get their heat delivery. You mentioned the pipe after the second floor zone valve gets hot so we can probably rule out a stuck done valve, sounds like it is opening as should.

Still sounds like air in the second floor heating loop to me. Take off your baseboard end caps, installers usually hide a bleed valve there, it looks like a fat thumbscrew. Usually at a change in direction, the first radiator that gets heat from the boiler has a bleeder, the pipe rises vertically from the basement and makes a 90 degree change in direction to other baseboards. Air can get stuck here.

 

[stormkroe]

^ pipe past the zone valve going to 2nd floor is hot. Pipes upstairs are warm.

The pipe past the zone valve can be hot simply from regular conduction too, are you sure that valve is opening? The pipe being hot there but only warm 15 feet away makes me think your zone valve isn't opening.

 

[Humpy]

I think those valves have a manual override lever on the bottom.

The pipes will get hot from conduction but you should usually be able to feel the difference between the supply and which returns are flowing or not. The valves are on the return side.

 

[rh71]

Still sounds like air in the second floor heating loop to me. Take off your baseboard end caps, installers usually hide a bleed valve there, it looks like a fat thumbscrew. Usually at a change in direction, the first radiator that gets heat from the boiler has a bleeder, the pipe rises vertically from the basement and makes a 90 degree change in direction to other baseboards. Air can get stuck here.

None of the baseboard pipes upstairs have the air bleeder at the elbows unfortunately. I followed some videos on how to bleed out at the boiler for that zone using the spout/valve right above the zone valve (far right vertical pipe in the last pic). Basically turned off the boiler, put a hose on that valve, switched open the zone valve manually, and put the other end of the hose down a drain... steaming hot water came out and heard some gurgling which meant air.
I stopped after the gurgling stopped for a while though the water kept coming.

On the 2nd floor (boiler is newer than the 2nd floor addition), there are 4 rooms plus a master bath and hall bath. After a half hour post-bleed and heat running on the 2nd floor only, all baseboards range from hot to warm, but again, inefficiently warming the rooms. EDIT> it was on all night and never reached temp.

The valves are on the return side.

In my setup, I thought the zone valves were at the supply side because the boiler heats the water and the circulator sends it through whatever zone valve is open, up the pipe and into the 2nd floor. Then why is that release valve placed there if many videos show that you should bleed it at the return side and not the supply? I don't see another valve to use. I thought I had identified the return in the rear (barely warm water). Is it normal for the circulator to only do/show 1-2GPM (gallons per minute)? Currently it's showing 0 GPM even when the 2nd floor temp is nowhere near the target but goes up to 2 GPM when the boiler is on. Perhaps the real issue is it's not circulating?

 

[Humpy]

In my setup, I thought the zone valves were at the supply side...

You are correct, I was wrong. Typically they are installed on the return to expose them to a little lower temperature. Its not a big difference though and either way is okay.

The GPM at the circulator will change depending on the number of open zone valves. Are there shutoffs that will allow each zone to be isolated? Check the manual for the pump, there are various settings.

 

[1sikbITCH]

This exact problem happened in my house, second floor radiators would not get hot. Circulator pump was the problem, water wasn't reaching the second floor.

 

[Thump553]

I had a similar problem this weekend, one zone in a three zone baseboard system couldn't call for heat in zero degree F weather.. I initially thought it was the thermostat, but swapping it out didn't do any good.

Turns out the problem was the zone valve heat. Easy fix, $85 part at Home Depot or Amazon.

I initially excluded the zone valve based on touching the pipes beyond the zone valve. The pipe was warm, probably because either I didn't reach far enough away from zone valve or because of the extreme cold the other zones came on often enough to get some circulation in the bad zone.

If you have Taco zone valves (very common), there is a lever on them. Push it down from Auto to Manual and the zone will be open all the time. If that gives you heat, replace the zone head. Twists right off, three wires to hook up, no plumbing to do.

If it isn't the zone valve my second guess is air in the system. As far as the circulator pump goes, in an oil fired system that's the electric motor hanging off the front of the furnace. If you don't hear that pump running very soon after your burner fires up, then that could be bad.