loop not hot
#1
12-25-08, 01:10 PM
loop not hot
I have a friend that called me - his heat was not working. It is a hot water system (same as mine).
I went over and this is what I found:
The boiler was hot and at 180. The top (feed) was hot just 2 feet away from the boiler. The return on the bottom had the circulater close to the boiler and it was cold on both sides. I asked him to turn the thermo up - Nothing. I took the thermo off and shorted the wires - still nothing. I thought I could feel and here the circulator, but it was still cold..
I tried to bleed the loop from the drain above the circulator, but there seemed to be no air as I did it, but I was able to get the 1st part of the loop hot by continued draining. I feel like the problem is the circulator. I wanted to test for power at the controller to see if it was supplying power to the pump but I forgot my tester. I am going back over tomorrow.
Any thoughts on further testing?
I went over and this is what I found:
The boiler was hot and at 180. The top (feed) was hot just 2 feet away from the boiler. The return on the bottom had the circulater close to the boiler and it was cold on both sides. I asked him to turn the thermo up - Nothing. I took the thermo off and shorted the wires - still nothing. I thought I could feel and here the circulator, but it was still cold..
I tried to bleed the loop from the drain above the circulator, but there seemed to be no air as I did it, but I was able to get the 1st part of the loop hot by continued draining. I feel like the problem is the circulator. I wanted to test for power at the controller to see if it was supplying power to the pump but I forgot my tester. I am going back over tomorrow.
Any thoughts on further testing?
#3
12-25-08, 03:50 PM
stick with that circ not running,if it was locked up it would of been hot to the touch.verify 115Vs off the boiler control or thru the end switch of the zone valve if you have one.the boiler is doing the hi-limit and satisfying because the water isn't being circulated.
#4
12-25-08, 04:42 PM
I asked him to turn the thermo up - Nothing. I took the thermo off and shorted the wires - still nothing.
Cuz if you really mean 'nothing', then the problem is 'something' else... maybe a fried 24V transformer, or maybe even the 'emergency' switch got turnt off, or a tript breaker at the panel...
#5
12-26-08, 04:59 AM
Trooper - sorry I was very unclear. When I said nothing I meant no hot water circulating. I did here the relay clicking. The boiler was already hot so it did not come on, but later it came on at low limit.
His boiler is piped differently than mine. I am pumping away, his circulator is on the return, about 1 foot off the floor. I see no zone valves - it is a very small cottage with only one loop.
There is one thing in the return line that I have no idea what it is. It is about 2 feet from the circulator, no electric to it, it is about 6" long and not all that much bigger than the piping. Could it be some sort of valve??
I also forgot to tell you - there is an air valve on the return up close to the cellar joists. I unscrewed the cap and nothing came out - no air no water - tapped on it and still nothing.
Pressure on the system seemed fine.
His boiler is piped differently than mine. I am pumping away, his circulator is on the return, about 1 foot off the floor. I see no zone valves - it is a very small cottage with only one loop.
There is one thing in the return line that I have no idea what it is. It is about 2 feet from the circulator, no electric to it, it is about 6" long and not all that much bigger than the piping. Could it be some sort of valve??
I also forgot to tell you - there is an air valve on the return up close to the cellar joists. I unscrewed the cap and nothing came out - no air no water - tapped on it and still nothing.
Pressure on the system seemed fine.
#6
12-26-08, 05:34 AM
I'm probably gonna go with the circ not circing then...
It could be a flow check valve ...
Exactly how find did it seem to be? i.e. PSI @ TEMP ?
What circulator is on the system?
Could it be some sort of valve??
Pressure on the system seemed fine.
What circulator is on the system?
#7
12-26-08, 05:41 AM
I think the psi was around 16-18. I'll check again when I go over today. The circulator looked like one of mine, a green Taco, but very old looking.
I figured I would replace it with another Taco from Home Depot.
I figured I would replace it with another Taco from Home Depot.
#8
12-26-08, 07:23 AM
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Taco Circulator
Before you go to HD make sure the circ is getting power (measure at the circ). Also measure the circ from flange to flange. Some of the very early Taco cartridge circs were different than those today. The modern ones are 6 3/8" & the early ones were 7 1/4", I think.
#10
12-26-08, 08:35 AM
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If it has an internal flow check (IFC) they are known for getting airlocked! Something else to consider.
Pete
Pete
#13
12-28-08, 06:10 PM
Well - guess what......... I am ashamed to tell you all that the valve next to the circulator was closed 
. We both checked it and thought it was open a few days ago just before I started this thread. We also had no reason to think it was closed, but apparently during the summer, my friend had someone working on the boiler and that person must have closed the valve. I found it when I tried to close it to isolate the pump before replacing it. I could'nt budge it. It was frozen. It took a great deal of force to open it. This was a big lesson learned and I thought I should pass it on to you all. Thanks for all the input, as always.
. We both checked it and thought it was open a few days ago just before I started this thread. We also had no reason to think it was closed, but apparently during the summer, my friend had someone working on the boiler and that person must have closed the valve. I found it when I tried to close it to isolate the pump before replacing it. I could'nt budge it. It was frozen. It took a great deal of force to open it. This was a big lesson learned and I thought I should pass it on to you all. Thanks for all the input, as always.
#14
12-29-08, 02:23 PM
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Closed Valve
I take it you got the valve open & all is now well without having to replace the circ?
Don't feel bad about the valve, that dog has bitten many of us.
Don't feel bad about the valve, that dog has bitten many of us.
#15
12-29-08, 03:43 PM
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Originally Posted by tomfmal
Well - guess what......... I am ashamed to tell you all that the valve next to the circulator was closed . .
. .
