Themostat in one room/zone controlling the heat in another room/zone...Crazy to think this?

Sorta

Hi all. Thanks for helping me out. I've had a wild week+ of dealing with boiler issues and not-so-great service solutions.

I have two rooms that are still having heating issues. One room is a room in the basement, the other is the room directly above it on the first floor. they are on two different zones. The weird thing is... if I turn-down the thermostat in one room (basement), the heat/temp goes down in the upstairs room.

Am I crazy to think this? How would the wiring be configured (wrongly) that could cause the issue I describe?

One tech that came out messed-around with the wires at the boiler heating zone valves. I getting a funny feeling that perhaps he confused the wires at the boiler.

Many thanks for reading and for your replies!

bburd

It's certainly possible, and shouldn't be hard to figure out.

Turn down all of your thermostats until the radiators go cold. Then turn them up one at a time, several degrees above room temperature, and see which radiators get hot.

If you have baseboard, you are likely to notice the heat only above areas with finned elements, not in areas where bare pipe alone runs through the enclosures.

Another possibility is that you have a zone valve with a bad end switch that cannot start the boiler or circulator, and that zone will only heat when one of the other zones is also calling.

Mad Dog_2

Exactly...ice cold start and move quickly throughout the rooms.  I also write ✍ everything down on a time line..'master bedroom  .1/2 hot 1203am...et cetera."   Then, from time to time , you can step back and make a decision.   I have found Zome valves and "split hot water systems the most difficult to diagnose because everything is often buried in walls & ceilings so its a visualization game.  Little by little you will learn the intimate secrets of the system.  MaD.Dog 

HVACNUT

The Zone valve issue is more likely but if you're fairly new to the house and not familiar, I've seen plenty of boilers wired where one zone would engage the burner and its circulator, and the other zone would only engage its circulator. 
Ridiculous I know, but they're out there. It's usually a one zone house, then a basement is finished, or an addition put on the house, and the additional zone is added and not wired right.
Can you post some pics of the boiler and surrounding piping and controls? Not too close.

Sorta

Thanks for the helpful replies all. Good to know my thought isn't crazy.

I think I'll try the method of turning off the all the thermostats, and turning back on one at a time. Great idea.

Thanks again all.

Sorta

Here's a question...what actually would cause the thermostat in one room to control the heat in another? I'm sure it would be a wiring issue on the zone valve (I think at the boiler end).

But what would the wiring mistake be?

How would I go about fixing it?

delta T

There is a wire going from each thermostat to the zone valves. Each zone valve is connected to the piping for their own specific zones. If the wrong thermostat wire is connected to the zone valve, the wrong zone will heat when the thermostat calls. Easy to switch thermostat wires when nothing is labeled. I've done it before....

109A_5

Hello @Sorta,
This is where wiring neatness counts. When the wiring is neat the errors are generally easier to spot. You really need to learn your system and how a system like yours is supposed to be wired up.

Without pictures the folks here can only guess what you have.

Like others have stated, I would verify the problem first. Then in the process of learning the system and typical system architecture (wiring, control and piping) the error (assuming there is one) may simply become obvious.

Sorta

An update & solution! Yep…turns out I was correct and the "pro tech" had wired the thermostats for two rooms to the wrong zone valves. And even after I advised to him that this was my suspicion, he ignored it.

I solved it myself by asking here, learning, and then tracing the thermostat wires and pipes from/to the boiler. Had to cut some ceiling sheet rock and pull down some panelling. All repairable pretty easily.

But man…the tech's error made a big impact. Certainly won't be using this HVAC service again.

109A_5

Hello @Sorta,

With functionality verification, I'm puzzled why so invacive to the house ? Could you just have switched the wires at the zone valves from one unit to the other ? And if that did not repair the situation you just switch them back.

Sorta

Hi 109A_5. Thanks for your reply.

Yes, that is what solved the issue. The thermostat wires at the boiler zone valves were connected to the wrong zones. So by process of elimination, testing, etc. I discoverd which wires were correct for which zone…and rewired them.

Jamie Hall

In @Sorta 's defence, @109A_5 , there are times when one simply can't believe that the problem is as simple as it is — or that someone who should know what they are doing could make such a simple error —and you do additional work. I've done that…

109A_5

Hello @Jamie Hall,

I believe you can apply a set of rules to troubleshooting. And folks that troubleshoot often do it intuitivly and in a logical order.

In this case I believe @Sorta was on the right track and the contractor dismissed his concern or the contractor actually caused the problem, not sure of the time line here. If I was @Sorta I would have ran with that gut feeling, possibly deviating from troubleshooting logic for a brief moment. And there are usually multiple EASY ways of verifying wiring it without disasembling part of the structure. Taking the house apart to trace wires and then having to repair it seems to me as the hardest and most time consuming and distracted from the actual task at hand method posible, hence my confusion.

If that was the easiest way for him, I am good with that, just not the way I would have done it. When you repair things for a living you want to find the most efficient method. I understand a home owner just doing it once may not be as eloquent. And I was curious if there was a reasion for that method that was not stated.

If the wire was believed to be broken in a wall by rodents or a nail that would be another story. I believe that was not the case here.

He did repair it so he is happy, so another successful DIY and another contractor's failure. I don't like paying for failure, who does?

Dave Carpentier

Once you're satisfied that everything is where it's supposed to be, tag label the wires and the zone valve positions. Words like "North Bdrm" are better than "Lisa's Bdrm", for potential future owners.

Jamie Hall

One of my rules, @Dave Carpentier , is to tag everything. Wires, switches, valve function, valve control positions. But i'm getting on, and I know that sooner or later I'm not going to be the one fiddling. I use the soft copper plant labels, embossed with a stylus.

Dave Carpentier

@Jamie Hall - I do think about my "getting on" and yes Im sure some future user would appreciate some kind of understanding of a system. But also, the whole "getting old" part occationally has me staring at a connection or setting and wondering "Uh oh, I forget why I did this"