There's 24V AC on thermostat but no heat

NYCBirdy

Hi!
I live in a 2 story house, which I lived in the 1st floor. I check the 2 wires from thermostat, there's 24VAC. But when I select higher temperature, no heat. Then I cross the 2 wires together...no heat. There's gas because the 2nd floor heater is in the basement which is on and I also can feel the warmth from the pipe. Can anyone tell me what's the problem?

Thanks!

Jamie Hall

If you cross the two wires together and the problem persists -- it's not the thermostat.

However, there are many other possibilities. You say "the pipe is warm", but is this steam or hot water heat? While some possibilities -- such as a broken wire -- are common to the two types, many are not.

EdTheHeaterMan

You mentioned that there is gas in the building. How many gas meters are there? If there are separate heaters for the first and second floor, there may be separate gas meters for the first and second floor. I have answered service calls from competitors that called me when the problem got too technical for them. Like a gas boiler that has electric and the glow coil (HSI) works but the darn thing just won't light, only to find the gas meter was locked off.

The new tenant never called the gas company to open an account. The heater worked for 2 days then just stopped. Because the gas company was 2 days late in shutting off the gas.

Do you have access to the basement where the 2 boilers are? You can look to see if the gas valve is closed at the meter or at the gas pipe that feeds the boiler itself. If the meter is locked, then you must call the gas company. If the valve is just off, then you may want to call the landlord to see if there is work being done. Someone may have forgotten to open a valve after completing some work.

DON'T TAKE IT UPON YOURSELF TO JUST OPEN A CLOSED VALVE. There may be work in progress and you don't want to open a gas valve to a broken pipe or uncapped disconnected appliance

Mr.Ed

NYCBirdy

Jamie Hall said:

If you cross the two wires together and the problem persists -- it's not the thermostat.

However, there are many other possibilities. You say "the pipe is warm", but is this steam or hot water heat? While some possibilities -- such as a broken wire -- are common to the two types, many are not.

Jamie, that warm pipe is from the 2nd floor heater.

NYCBirdy

EdTheHeaterMan said:

You mentioned that there is gas in the building. How many gas meters are there? If there are separate heaters for the first and second floor, there may be separate gas meters for the first and second floor. I have answered service calls from competitors that called me when the problem got too technical for them. Like a gas boiler that has electric and the glow coil (HSI) works but the darn thing just won't light, only to find the gas meter was locked off.

The new tenant never called the gas company to open an account. The heater worked for 2 days then just stopped. Because the gas company was 2 days late in shutting off the gas.

EdTheHeaterMan, yeah...could be the meter is turn off. I try that. Thanks!

NYCBirdy

NYCBirdy said:

EdTheHeaterMan said:

You mentioned that there is gas in the building. How many gas meters are there? If there are separate heaters for the first and second floor, there may be separate gas meters for the first and second floor. I have answered service calls from competitors that called me when the problem got too technical for them. Like a gas boiler that has electric and the glow coil (HSI) works but the darn thing just won't light, only to find the gas meter was locked off.

The new tenant never called the gas company to open an account. The heater worked for 2 days then just stopped. Because the gas company was 2 days late in shutting off the gas.

EdTheHeaterMan, yeah...could be the meter is turn off. I try that. Thanks!

wait...it can't be the gas meter is turn off because my water boiler is on. What other things that's causing me not getting heat?

EdTheHeaterMan

EdTheHeaterMan, yeah...could be the meter is turn off. I try that. Thanks!

wait...it can't be the gas meter is turn off because my water boiler is on. What other things that's causing me not getting heat?

The service valve to the boiler could be closed. How old is the boiler? Could the pilot be out?

JohnNY

There are 50 things it could be. Post some pictures of the boiler and maybe someone can help you from that point.

NYCBirdy

STEVEusaPA

It’s broke. You can’t fix it yourself. Call a tech or if you rent, call your landlord.

NYCBirdy

STEVEusaPA said:

It’s broke. You can’t fix it yourself. Call a tech or if you rent, call your landlord.

what broke?

EdTheHeaterMan

NYCBirdy said:

STEVEusaPA said:

It’s broke. You can’t fix it yourself. Call a tech or if you rent, call your landlord.

what broke?

It could be the Gas valve, the high limit, the low water cut off, the thermostat, the spill switch, the transformer, the vent damper, the end switch in the vent damper, the circulator relay, the burner relay, secondary safety, a Kronston valve, The Finigan pin, the flux capacitor, the muffler bearings or maybe even the blinker fluid. It might just be the wires that connect these things.

It is tough to tell from the picture without a multi-meter

Here is a video on how to DIY the blinker fluid.
https://www.youtube.com/watch?v=E6GsXhBb10k

NYCBirdy

EdTheHeaterMan said:

NYCBirdy said:

STEVEusaPA said:

It’s broke. You can’t fix it yourself. Call a tech or if you rent, call your landlord.

what broke?

It could be the Gas valve, the high limit, the low water cut off, the thermostat, the spill switch, the transformer, the vent damper, the end switch in the vent damper, the circulator relay, the burner relay, secondary safety, a Kronston valve, The Finigan pin, the flux capacitor, the muffler bearings or maybe even the blinker fluid. It might just be the wires that connect these things.

It is tough to tell from the picture without a multi-meter

Here is a video on how to DIY the blinker fluid.
https://www.youtube.com/watch?v=E6GsXhBb10k

Like I stated before, there's 24 VAC when I use the multimeter. So it ain't the transformer and thermostat (when I cross the 2 wires).

HVACNUT

Then vent damper isn't even open. 
Is seems a safety has tripped and you need a pro to repair the problem. 

JUGHNE

There are about 10 more devices that need to be happy for your boiler to fire.

This is your landlord's responsibility to provide heat.

And if you are in NYC there is probably an ordinance to provide heat to tenants.

STEVEusaPA

NYCBirdy said:

STEVEusaPA said:

It’s broke. You can’t fix it yourself. Call a tech or if you rent, call your landlord.

what broke?

Something in your heating system.

Jamie Hall

We are not trying to be difficult, @NYCBirdy . The problem is this: if it's not your own thermostat, and you have demonstrated that by getting the same result (that is, no heat) by crossing the wires at the thermostat -- which is all the thermostat does internally -- the problem is elsewhere in the heating system. As someone said, there are a number of other possible causes for this problem.

There are ways to troubleshoot this, which a competent tech. would be aware of. If this were your private residence, and you were the owner, we might be inclined to make some suggestions as to what to try. However. You are not the owner, as I understand it, and this is New York City. To work on someone else's heating system (or pretty much anything else) you need to have a professional license, which ensures that you have at least minimal training in the field (not that all licensed pros are good, but that's another story)(this is true not only in New York, but in most of the country). New York has -- and New Yorkers have -- a reputation for being somewhat difficult if things go amiss.

So... while I would encourage you to learn as much as you can about your landlord's system, I can't really encourage you to attempt repairs, and, much as I might like to, I really can't recommend you doing this or that.

pecmsg

Jamie Hall said:

and New Yorkers have -- a reputation for being somewhat difficult if things go amiss.

HomerJSmith

Ed, you forgot to mention the Thelman wire as a possible cause. (Mad Magazine) Everything I ever needed to know about the world, I learned by reading Mad Magazine.

NYCBirdy

Thanks guys!

NYCBirdy

One more thing. Whos should I call to fix the heater? HVAC or plumber?

JohnNY

NYCBirdy said:

One more thing. Whos should I call to fix the heater? HVAC or plumber?

Where are you located? Zip code is fine. I'm 10014.

NYCBirdy

JohnNY said:

NYCBirdy said:

One more thing. Whos should I call to fix the heater? HVAC or plumber?

Where are you located? Zip code is fine. I'm 10014.

11375. JohnNY, what's your rate for just determining the problem?

HomerJSmith

Ok, this is my stupid day so I'll ask some stupid questions.

Is the service disconnect switch on the side of the boiler switch on?

That doo hicky on the side of the draft hood with the two wire connect to it, we call it a blocked flue thermodisc or spill switch have a red button between the to spade connectors? If so press the red button to reset the thermodisc. I assume that if you have 24V at the thermo wires that the 24V safety circuit is intact, tho.

It is, I assume, standing pilot boiler and you have a pilot flame or is it intermittant ignition?

Does this boiler have adjustable boiler controls?

That gray box on the side of the green boiler under that red thingy with the switch on it is an aquastat? The aquastat is activated by the thermostat. It has a relay in it that turns on the pump and fires the boiler by opening the gas valve. Sometimes these fail. What is the model #. You can pull the cover off the aquastat and read the label inside.

Is the pump turning when the thermostat calls for heat?

I don't know if this applies to your boiler.

https://www.williamson-thermoflo.com/sites/default/files/field-file/GWA Boiler Manual 550142784_1212.pdf

Erin Holohan Haskell

NYCBirdy said:

JohnNY said:

NYCBirdy said:

One more thing. Whos should I call to fix the heater? HVAC or plumber?

Where are you located? Zip code is fine. I'm 10014.

11375. JohnNY, what's your rate for just determining the problem?

@NYCBirdy, we can't discuss pricing in the forum. Thank you!

pecmsg

NYCBirdy said:

JohnNY said:

NYCBirdy said:

One more thing. Whos should I call to fix the heater? HVAC or plumber?

Where are you located? Zip code is fine. I'm 10014.

11375. JohnNY, what's your rate for just determining the problem?

Hes worth every penny and more!