Forced hot water heat question

[frankjc]

My forced hot water heat has 2 zones, 1 upstairs, and 1 downstairs. The downstairs works fine, but upstairs does not. I tried it for the first time last week (I bought the house in July), and discovered this. I had originally thought the problem was with the "taco 219 flo-chek" valve, because there was a temperature difference on either side of the valve. I unscrewed the knob at the top of the valve, and it didn't seem to make any difference. I didn't leave it like that for very long. Looking around (and not really knowing what I am doing), I started to suspect the circulator. At first I thought I heard it making a noise, but now I am not so sure. The "downstairs" circulator is hot, the upstairs is not. I can hear a clicking noise inside the controller when the upstairs thermostat is turned on. I have not verified whether there is power getting to the upstairs circulator. The flange at the circulator was repaired before I bought the house because the home inspector noticed it was leaking, I don't remember him checking the upstairs heat. I know that there were also pipes in the house that froze and bursted last winter, so I don't know if it has anything to do with that.
I really know nothing about this type of system, and if anyone could offer any advice or suggestions, it would be greatly appreciated. Thank you. Frank.

[xiphias]

If the pipe on the downstream side of the flowcheck is cold, and the circulator is not warm, that probably means the circulator is not running on a call for heat. A running circulator gets hot.

The temperature difference you feel across the flowcheck is caused by the flowcheck doing its job in not allowing hot water to flow through the upstairs zone when only the downstairs is running.

If you have a multimeter and are comfortable using it, verify that you have power from the thermostat, and that you have power going to the circulator.

[frankjc]

Thank you for the fast reply. I will check for voltage at the circulator and see what I come up with. Hopefully I can fix this myself. Thank you.

[frankjc]

Well, I think I proved myself wrong. I turned on the heat and touched the circulator, and it felt like it was pumping, so put my maglight on both of them, and put my ear up to the other end, and they both sound like they were working. I opened up the Taco 219 flo-chek valve and waited a while, and I now have heat upstairs. I am not sure what made the heat work.... Bad flo-chek valve? Maybe I didn't give it enough time before for the hot water to make it's way upstairs? Anyways, I think I am going to give it a while and put the valve back the way it was (which is the same way the downstairs valve is) and see if I have no heat again. If it goes back to no heat, does that point to a bad flow-chek valve?
Thanks.

[NJ Trooper]

Frank, if the check valve is on the discharge side of the circulator, it is possible for an air bubble to collect at that point. If there's enough air there, the circ will just spin and not pump anything... [theory] maybe opening the 219 allowed that air bubble to move and the pump to start pumping... [/theory]

[aandpdan]

You may have also had some air in the system. Usually the higher zones are more susceptible. The circulator can't move water past the air and you'll get no heat.

If it happens again, try bleeding the baseboards.

[frankjc]

Thank you. That would lead to my next question....how would I bleed the air out?

[Mike Speed 30]

Originally Posted by frankjc

....how would I bleed the air out?

Look for manual bleeder valves on either end of each baseboard. Open them, one at a time, until a stream of water comes out.

[frankjc]

I don't see anything like that. There is what appears to be one continuous loop of pipe going through them. On the top it's a plain pipe, I am guessing for return? The bottom pipe has the aluminum fins on it. I am not 100% sure that the circulator is in fact running. The downstairs one is considerably hotter than the upstairs side. I have to open the check valve to get any kind of heat upstairs. When I do this, it seems that the return pipe, close to bottom of the furnace gets hot first. Is that the way it should be? Is it at all possible that the upstairs zone will not work if the downstairs is not calling for heat? I am thouroughly confused at this point. I am almost ready to call in a professional.

[NJ Trooper]

it seems that the return pipe, close to bottom of the furnace gets hot first.

Is it at all possible that the upstairs zone will not work if the downstairs is not calling for heat?

Yes, it's possible... that the upstairs circ isn't pumping, and what is happening is that when you open the check valve, that is allowing the downstairs pump to pull water through the upstairs loop, in reverse... and that's one of the reasons for the check valves to even be there... that, and to prevent 'gravity flow'.

Did you mention what brand/model of circs you have? Is there a round plastic plug in the center of the motor end, with a screwdriver slot in it?

[NJ Trooper]

Frank, take a step back and follow Xiphias' lead. Get out the multimeter and verify that you have power to the circulator first.

Then, go from there...

and tell us what pumps you have.

[frankjc]

Ok, I found my multimeter, and found that I have no power going to the upstairs circulator. I verified that I have power going into the controller. My controller is a Honeywell R8845U, and on the cover there is a diagnostic chart, it says if the "call" LED is lit, and the "relay" light is off, replace relay. I am not sure if it means replace the whole unit, or the little clear relays. If I look inside the relays, it looks like the contacts are closed on one, but not on the other. Is it possible to bypass the control to test the circulator? My circulators are Taco 007-f cartridge circulator (if I recall correctly, I may be wrong on the exact number).
Will there be any adverse effect from opening the check valve to get a little heat upstairs until I can get this fixed?
Thank you.

[NJ Trooper]

it says if the "call" LED is lit, and the "relay" light is off,

and this is exactly what you have?

Check first to make sure all the connections are clean and tight ... REMEMBER TO TURN OFF POWER! 120VAC INSIDE! ...

I think they are suggesting replacing just the plug in relay inside, rather than the whole thing, but a new 8845 is somewhere around $50 :

Honeywell R8845U1003 - Honeywell - Universal Switching Relay w/ Internal Transformer

And for some reason, it seems that Honey has 'obsoleted' the suggested replacement part # 32002190-001 , which is also used in some of their other controls... guess they would rather you buy a whole new part than sell the individual parts...

but, take a look at the relay, and take all the numbers and what not off of it, and google up whatever you find... you may be able to find a replacement.

any adverse effect from opening the check valve to get a little heat upstairs until I can get this fixed?

None whatsoever... that's actually WHY they have the knob on them so you can open it in the event of a circ failure.

[frankjc]

Yes, That's exactly the LED pattern that I have. It's like that when I turn the thermostat up, or press the test button.
Connections look pretty good.
I did some poking around tonight, I traced the wires coming into the R8845U, and out. It seems a white wire goes straight through, and a black wire goes in the box to one connector, then from another one, then out of the box to the circulator. I have voltage when I connect my multimeter between these 2 terminals. I connected my multimeter to the connections on the circulator, then put a jumper wire between the 2 terminals with the black wires, and then it showed voltage at the circulator (the "relay" LED lit up when i did this. I do not know if the pump ran when I did this, the pipes did not seem to get as hot as the other zone. I can definately hear the noise from the pump on the other zone, and I can hear something in the bad zone, but I think it's residual noise from the rest of the system.
I checked a few supply houses today, and none stocked the relays, but they all had the whole thing. The prices ranged between $55 and $75, and I think I saw them well over $100 online. Does it seem likely that I need to replace the R8845U and start from there?
Thank you.

[frankjc]

Yesterday, I wited a cord directly to the circulator, and it didn't run. Like an idiot, I decided to reverse the wires, and I heard a ZZZT ZZZT sound, so now I have probably also fried the capacitor.
At this point, I am thinking that I need a relay and a circulator.
When there is a call for heat, I have no power at the circulator, and the relay light doesn't light up at all. This is the part that makes me think that the relay is fried. Does a burned out motor ever take out the relay too?
When there is a call for heat, or I press the "test" button, the boiler does kick on.

[NJ Trooper]

frank, when you say stuff like "a black wire goes in the box to one connector, then from another one, then out of the box" it really means nothing to us... You would need to tell us exactly how the entire thing is wired up... terminal numbers, etc for it to have any meaning at all, and then without pictures, it still will probably mean much.

then put a jumper wire between the 2 terminals with the black wires,

This doesn't mean much either, but it DOES scare me a bit... you DO realize that there is 120 VAC in that box, right? You really ought not be putting jumpers on terminals that you don't know what they are!

I wired a cord directly to the circulator, and it didn't run. Like an idiot, I decided to reverse the wires,

I wouldn't say that... it's AC, and the polarity really shouldn't matter. And the pump should run either way. As long as you have the line cord wired to the correct points anyway... but it possible that the circ is bad, and that it fried the relay in the 8845.

[frankjc]

Update. Still not fixed, I have had too many things going on lately, car trouble, etc. At this point, I am thinking I need a relay and a circulator. I can figure out how it's wired when I get home, and post it. The fact that I get no power at the wires that go to the pump make me think I need a relay, and the fact that the pump doesn't come on when wired directly to the wall outlet lead me to believe the pump is dead.
The local supplier stocks the R8844U relay for $55, and the Taco 007-f5 circulator for $95.

[frankjc]

OK, I think the R8845U is wired correctly, but I am not sure.
There is a black "hot" wire into the box, connected to L1.
A black wire goes from L1 to COM.
A black wire goes from NO out of the box to the circulator.
A white wire goes into the box, to a wire nut.
2 white wires come out of the wire nut, 1 goes to L2, the other goes out the box to the circulator.
A red wire goes to X1.
A blue wire goes to X2.
A red thermostat wire goes to R.
A white thermostat wire goes to W.
Nothing is connected to B or C.

If I were going to change the circulator, could I close the valve that sits just above it, and partially drain the boiler, or do I have to drain the whole thing?

[NJ Trooper]

Frank, it sounds as though you have wired the relay correctly.

Nothing is connected to B or C.

Which is correct, but you should also have nothing connected to A either.

The red and blue wires on X1 and X2 are going to fire the boiler, correct?

If you just close one valve, you will still have water coming up from the other side of the pump.

If you are able to isolate ALL the zones, both supply and return, then you may be able to partially drain the boiler... remember gravity is going to want to put that water in your face, via any route it can take. Look over the piping and try to determine if you can isolate most of the system.

[spot8]

Frank, you can shut the valve off above the circ and drain the water below the circ flange in the boiler to change it. Make sure both flo-check valves are closed so you don't feed back through the supply. Back to the relay for a minute. On a call for heat did the call LED light up. If it didn't push your test button. If it lights then check your t-stat. It should light on a call for heat and then when the pump is energized the other LED comes on. The control seems to be wired properly. Where does your x1 &x2 wires connect into. What control are these wires going into. If you run a direct wire to your circ to check it remove the wires from the relay so you won't it out. With your meter you should have 120v at 1&2 and 2&C. 2 also goes to the circ., N.O. goes to the circ also. Black is your hot, white is neutral. X1 & X2 go to R&R terminals on your aquastat control. You should have 24V at the t-stat terminals on the control and from X1 & X2 to aquastat, which will energize the burner. To check your s-stat you can always jump the red and white on your t-stat, ther only 24v and nothing will happen. If you jump your s-stat and the LED comes on and the pump runs change you stat. If you want to open your flo-check for now to get heat upstairs you canwithout any problem. The system will just become one zone until you find the problem.

[frankjc]

The relay LED never lights up.
I think the red and blue (x1 x2) wires go to the aquastat box.

[NJ Trooper]

Good, that's where the X1 X2 should be going, and most likely in parallel with the same contacts on the other relay...

Spot, yer pretty much reinventing the wheel... that stuff was all covered in earlier posts... it's your time though!