malfunctioning thermostat

Vero

Hi, it was 15 degree Farenheit outside when I woke up this morning, and 49 degrees inside my house.

First I checked the water level, and it was fine. I've been out of heat before, and when I increased the water level, the furnace would restart. In April the plumber came and disconnected the autofeedt. I told him that the autofeed had functioned just fine in the 13 years that i have lived in this house. He responded that I was simply lucky. Now I have to constantly add water to the system. But that wasn't the problem this morning, but it will be a problem should I ever go on a winter vacation.

Anyway I turned the thermostat to the max, 90 degrees F, and the heat kicked in. So I figure it's the thermostat. The plumber is supposed to come to look at it tomorrow. This is a fairly new thermostat, maybe ten yrs old. What is likely to be the problem? the unit itself? or the connection going from the unit to the furnace? The furnace doesn't seem to be the problem; it is only about four years old. Do I call the plumber or the electrician?

I appreciate your insight.

nicholas bonham-carter

heat off

if you have to add water to the system, on a regular basis, then that is a real problem. fresh water contains lots of dissolved oxygen, which when added to the iron of the boiler equals rust!

when your heating professional comes to check out the thermostat, why not get him to check the more serious problem of some sort of leak. otherwise, some morning, the thermostat may work fine, but the boiler will not!

if the thermostat is an old mercury bulb type, then perhaps the anticipator has become too anticipatory!--nbc

Vero

Old wiring?

Thank you NBC,

I will do just that: ask him to check for leaks. In your experience do the autofeeds malfunction a lot?



My thermostat is a Honeywell digital unit. The unit is pretty new, but the wiring from the thermostat to the furnace may be very old. No way of telling. My house is very old, and I understand that it was unheated until the 1920s. I don't know if they made thermostats back then, but the wiring could be very old. I know that the electrician had trouble with the door bell wiring, so he simply set up a totally new connection. He said it was easier than trying to find where the old one was malfunctioning. If it is the wiring, who does that? would an electrician know where the wire from the thermostat needs to be connected to the furnace? or would the plumber do this electrical job?

Hap_Hazzard

Autofeeders

I've seen a lot of posts here reporting problems with autofeeders. They are responsible for a lot of boiler flooding issues. I think part of the problem is that many people see them as a convenience device rather than a safety device, so they're being called on to do something they weren't really designed for. That seems to be the case here. They're not intended for routinely refilling the boiler or as a substitute for weekly maintenance. You still need to blow down your LWCO, if it's a float type, top up the water level, and keep track of how much make-up water you're using. The autofeeder is just there to keep the system operational in case it suddenly loses water for some reason. Normally you shouldn't lose much water from week to week. If you do, something's wrong, and automatically adding more water isn't the solution.

nicholas bonham-carter

Old wiring

Check the batteries in the thermostat, as I have seen some stats give no warning, and just revert to a very low setting when the batteries go bad.

Call the plumber first, and he can jumper various terminals together to simulate a call for heat. If the boiler fires when jumped at the boiler, and then at the stat, then it must be the stat at fault.

Some boiler controls are very sensitive to a good electrical ground..--NBC

Jean-David Beyer

Check the batteries in the thermostat, as I have seen some stats give no warning

Yes, and sometimes it may not be the fault of the thermostat. My high sensitivity CO detector comes with a Lithium 9v battery. These should probably last about 5 years, but the first one lasted only a year. The second one lasted only about a month. The third one is up to 4 months and is still running. You never know how long the batteries have been deteriorating on the shelf before they are sold to you.



I change all my batteries  on September 1 (the start of the ehating season). But that does not handle the case of early battery failure.

Jamie Hall

Replied to other thread

on same topic.



The thermostat, if that's the problem, is easy.



That water usage is not normal, however.  As nbc noted, you have to have a leak somewhere -- find it and fix it.  They never get better on their own.

Vero

THANK TOU!

I feel more confident now that I have heard from you all. The plumber I called is a new plumber, because the young, licensed plumber who had been taking care of my system, someone a friend recommended highly, flew the coop when there were problems he couldn't resolve. Not only do I still have a problem with heat, now I have a problem of confidence with my plumbing professionals.



I am sure it is the battery, because I don't recall ever changing it. But that doesn't mean that there may not be other issues going on with leaks or maintenance. I will have the plumber look at it all today.



I am a single female, and sometimes I feel Iike my service men's long, lost, winning lottery ticket. Revenue with little effort.



I will report what happens; stay tuned

Vero

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Vero

bad batteries

I dismantled the thermostat, and one of the batteries had exploded its contents onto the device; I am amazed that the furnace worked at all. Nice job, guys. You found this problem for me.



Now I have to keep my eye on the water level and find out from the plumber if it needs to be serviced again given that it was March/April of this year. Hopefully, it was just the batteries and nothing else.

Vero

Too much of a good thing?

So, what's an LWCO? I am a homeowner trying hard to get rid of her attitude.

I do routine maintenance on the furnace every week. The furnace is next to the washing machine, so every time I do laundry, I drain half a gallon from the furnace and replace it with clear and fresh water. From what you write, perhaps I am doing it too much, maybe I am putting oxygen and causing rust to accumulate. Is once a week to bleed half a gallon of water from the boiler too much?

The time I discovered that putting water into the system kicked started my Lennox furnace the glass tube was only 1/3 full. Now I keep the glass tube about 55-60% full.

How does one check for leaks? My house is very old, probably from the 1700s, and the foundation is extremely old. It has cracks, so it is difficult to say if the moisture under the furnace comes from the furnace or the cracks on the foundation of the house. There are no pools of water, but I do see that it has a different color from the rest of the foundation.

I appreciate your comments.

Vero

SUCCESS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Plumber came. I told him about the battery leaking contents onto the thermostat. He checked the programming: all good.

Then we went to look at the furnace. He told me that my Lennox doesn't need to be drained every week, my old furnace needed it, but not this one. He told me to check the water level every two weeks. Then he showed me that I was not giving the furnace enough water. I am filling the glass 50-55%, and it should be about 2/3 of the way up. There is a marker there that I never noticed for the water level. That's probably why giving it water was turning the furnace back on: not enough water to begin with. I am going to watch how much it needs from now on though I am not quite sure what constitutes an unusual amount of leakage. I guess I will measure it first, and then worry about what the results mean.

Then we talked about the leak. He says the darkness under the furnace is probably sediment from long ago. No problem now.

Then I told him that I did not service it this winter, because I serviced it in March. He says that it should be serviced at the beginning and not the end of the season. He said it will probably be OK for this year, given all that I reported about the furnace.

No charge for the service call, and he came with his helper. I offered to give him my dogs, but he said that he has 3 cats and a ferret, so he passed on the dogs.

I feel soooo relieved. Wow. Not only do I not have a problem, but I know more about how to take care of my furnace, and I have a plumber that I think I can trust.

Thank you, thank you, thank you.

ps I was just kidding about the dogs. I would NEVER give them up.

Hap_Hazzard

LWCO and finding leaks

An LWCO is a low water cut-off. It turns the furnace off when the water gets low. Yours is working, apparently. :-)



They come in two types: float or probe. From what your plumber told you, it sounds like you have a probe type. The float types have to be blown down every week to ten days, but the probe types don't.



When leaks happen, they are often found in the wet return plumbing. This is the piping that returns the water that condenses in the radiators back to the boiler. In finished basements these often run behind the drywall and framing, and the water that leaks out either runs into the sump and gets evacuated or soaks into the framing lumber and gradually evaporates unnoticed, but it rots the framing and causes mold to grow on the drywall in the process. By the time you actually see water on the floor, the damage can be extensive, which is why it's so important to monitor the amount of water you're adding. Not counting the water you add to replace what you're draining out, you shouldn't need to add much. A small amount of water vapor escapes from the radiator vents, and if you have a few bad vents they'll lose a little more, but you'd hardly notice it week to week.



Now that you know where the water level mark is on your gauge glass, you can keep an eye on it. Check it before you drain and refill and see if it's lower, but bear in mind that if the boiler has just shut down, there will still be a lot of water in the radiators and pipes. It takes a while for it all to drain back. The best time to refill your boiler is just before a heating cycle.

Vero

What does the return pipe look like? where do I find it?

Hap_Hazzard, I have a very old house, so that the ceiling in the basement is too low for it to be finished, It's great from the point of view that the guts are exposed. What does this return pipe look like? or where do I find it? I don't have any malfunctioning valves that I know of, because the plumber who flew the coop fixed all of that and completely rebalanced the system. He did a great job. He also did a great job with the piping of the water boiler in an environment of low ceiling, but I am digressing. It sounds as if checking this pipe for leakage would be a lot easier than measuring the amount of water that my system is loosing.

Jamie Hall

All of this can be sort of fun...

in a back-handed sort of way!  Nice to have an unfinished basement (the place I superintend has a mostly unfinished basement -- makes life much easier) as you can really see what's what.



On returns -- and steam pipes in general.  Almost all steam systems have three kinds of piping: steam mains, dry returns, and wet returns.  As has been said, wet returns are the most likely ones to leak.  The steam mains go from the boiler to the radiators; they should be insulated (we hope) as that saves you money and makes the system run better.  They will be hot when the boiler is running!  Dry returns are pipes which return condensate back to the boiler, but they run high -- usually just below the basement ceiling -- and most often right next to the steam mains, or very close.  They can be warm, but they shouldn't be hot.  Wet returns are usually down low, almost on the floor, but at a distance from the boiler they can be a couple of feet up the wall.  Both the dry returns (if you have them) and the steam mains may have pipes (often called drips) which go down to the wet returns.  The wet returns come back to the boiler near the bottom; the dry returns, if any, will drop vertically to the wet returns near the boiler.



Wet returns are more likely to develope leaks than the other lines simply because they always have water in them, and they rust from the inside.  They are also cool and down low, so they are often damp (and dirty!) on the outside -- so they rust from the outside, too.  Finding a leak, though, can be very very hard unless it is really obvious, because these pipes tend to be damp in most basements anyway.



I must admit that I'm a bit of a maverick about autofeeders on boilers.  I have one, and I advocate for them.  But mine is the sort which tells me exactly how much water it has fed to the boiler, so I can keep track of it, which I find rather handy.



Does any of this help any?