Home>Discussions>INSULATION & HVAC>forced hot water heat question
31 posts / 0 new
Last post
frankjc
forced hot water heat question

hi. i tried tonight to use the heat in my house for the first time. it is a "cape" style house, with forced hot water heat. the heat on the first floor worked fine, but the second floor never warmed up. i went downstairs by the furnace and was looking around and saw some sort of valve on the pipe that said "upstairs supply". before the valve, the pipe was too hot to touch, after it was warm, and it got progressively cooler as it got further away from it. i am not sure what this valve is, and i am going to try and post a picture of it. and help would be greatly appreciated.

Sten
Re: forced hot water heat question

Have you ever seen a gas shut off valve that has a direction line so you can tell if the gas is on or off? I'm not sure what the pic is of as it's not that clear but I would say it's some sort of a flow regulator or shut off. Is this the first winter in the house, if it is the last family that lived there might have shut it off. I would turn the square on top very slightly and see if the cold side of the pipe heats up. Don't turn it to much at first, if it warms up your all set, USE CAUTION. Good Luck !!! :)

frankjc
Re: forced hot water heat question

Thanks for the quick response. I will try that. It is possible that it was shut off and not turned back on. There were some pipes burst in the house before we bought it. In the mean time, here are some better pics.

NashuaTech
Re: forced hot water heat question

I would agree with Stan---the blue-green oxide on the top of the valve indicates that is has been rarely used in the past---there's usually no reason for a former owner to shut an "upstairs supply" line off unless one wants to bleed air out of the upstairs lines, or if there is a leak somewhere in the upstairs supply piping.

You should be easily able to trace this line back to the boiler (you have a boiler, not a furnace)---it should be connected to a larger pipe (perhaps 1" or larger) that is coming directly out of the top of the boiler, and is known as the "main (hot water) supply".

There is a circulator pump somewhere on the boiler that PUMPS the hot water thru the 1st floor & 2nd floor supply pipes out to the radiators/baseboard, then combines to a "main (hot water) return" line to return the cooled water back to the boiler to be reheated---the main return usually goes back into the boiler at the side or near the bottom of the boiler---an endless loop of supply water and return water.

Closely check the upstairs radiators/baseboards for any leaks after you turn the 2nd floor supply on---especially along exterior wall runs where the cold air may have penetrated a small crack in the siding/sheathing---especially along "prevailing weather" walls (usually north-facing)---supply & return piping for the 2nd floor rads are almost always run up the exterior wall cavities & are vulnerable to freezing/partial bursting----also check for any signs or sounds of water leaking at unseen places inside the walls or flooring----also check in the basement at the base of exterior wall cavities for any signs of water---hot water systems have a low water pressure of 12 psi (as opposed to 50-60 psi in the rest of the house)--designed to minimize water damage in the event of a heating system leak.

Also check the 1st floor ceiling plaster for any tell-tale brown stains that would signal a leak.

Gizmo
Re: forced hot water heat question

Its an isolation valve open it slowly............

frankjc
Re: forced hot water heat question

thank you all for your help. i will try it after work. luckilly it hasn't been too cold yet. does this valve just get opened all the way, or is there any sort of adjustment? thanks.

Sten
Re: forced hot water heat question

Full open should be fine. Good Luck!!! :)

frankjc
Re: forced hot water heat question

Well, unfortunately, that wasn't the problem. I am wondering if it is a pump problem? There are 2 parts that say "taco cartridge circulator" on them. The one connected to the "downstairs" side seems to ma a pumping noise, and is warm to the touch, the one on the "upstairs" side is not. When the upstairs thermostat is turned up and down, the controller clicks. I wonder if the circulator is either dead, or now getting power for some reason. I do remember that there was a connection in the vicinity of the circulator that was leaking and the home inspector pointed it out to the seller, and he had it fixed. I cannot recall if the home inspector checked the upstairs heat or not. I tried swapping the relays on the controller and it made no difference.

Sten
Re: forced hot water heat question

How long you been in the house??? Maybe you can get the previous owner to dig deep since a house has to have heat. If there is voltage going to the circulator and the stat is calling I'd say it's the circulator. I have limited knowledge with boilers but I'm sure that someone will come along and help you as best they can, NashuaTech usually stops in daily. Good Luck!!! :)

frankjc
Re: forced hot water heat question

I have been here since July 1st. There is power inside the controller, there are LEDs in there for diagnosis, and it seems that it is working ok. I should probably pull the cover off the circulator and see if I am getting anything there. If it gets expensive, I will talk to my realtor, and see what she thinks, I know she knows the sellers, who are also realtors. The house was a forclosure that they bought and flipped. I wonder how difficult it would be to connect the circulator that is not working to the circuit of the one that is, just for test purposes.
Thanks.

NashuaTech
Re: forced hot water heat question

Frank:

Yes, it is possible to test the circulator by attaching a 120v line to it, but first, please describe what equipment you have there.

From your post you infer that you have 2 zones (upstairs & downstairs) with their own separate t-stat that are controlled by 2 separate circulators & that they have separate "controllers"---some systems also use zone valves to separately control upstairs & downstairs.

The very first photo you published has a control in the lower left-hand corner that looks like a Honeywell R845 relay that is often used for circulator zones---and these sometimes go bad.

Please verify the equipment you have there to control the separate zones---& look to see if there is any numbering on the controls--any photos would also help.

Pages

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.