Return pipe on boiler really HOT!! Supply luke warm

I am a noobie to all of this and I am a young homeowner. I bought my house last year in September. Well, that winter I had issues with my gas boiler not heating 2 rooms in my home.

Since I have no prior knowledge of heating systems, I called a local plumber to fix the problem. I was off at work and my wife stayed while he (the plumber) handled business. He replaced the auto water feeder, expansion tank and pressure relief valve. He bled the system as well according to his notes. I got home everything seemed to be in working order. We went through that winter with no problems and everything seemed perfect.

Well, all until the following winter (this winter). First cold night we had the boiler firing up and heard awful banging in our pipes! I talked to a coworker at work who told me to bleed the radiators from the highest point in my 2 story cape. And to work my way down to the radiator closest to the boiler. I did some research before doing the work and decided to take on the task. I bled the radiators and the water hammer seemed to go away, but the next day it started back up. My coworker told me I must have not gotten all the air out to give it another shot. So, I did. It worked. No water hammer.

I have a 2 zone system with Taco zone valves with 1 Taco circulator pump. It is a Williamson gas boiler. I set my tstats typically at 70* and now I am noticing that one zone is not getting up to temp. It stays about 5 degrees lower than what it is set at. So I watched my boiler go to work in the basement and noticed my gauge on the boiler reading at 100* when not running and pressure is at about 20 psi. But when the boiler fires it only goes up to 110*-120*, pressure stays the same except the needle kind of shakes a little.

I borrowed an infrared temp gun from work and it matches what the gauge is reading. But I also noticed my supply lines are cold and my returns lines are HOT. I put the infrared to the return lines and they are around 140*-150*. My buddy says I still have air but I've bled the radiators literally everyday for a week now. And I'm finding that no air is coming out just water. I am bleeding while the boiler is firing, is it something that I am doing wrong?

Can someone please help me out? I have had so many issues happen with other things (both my cars and my washer crapped out) so I don't have too much money to give out. With the weather being cold now(I am in Connecticut) and having 2 small children I would really like to resolve this issue.. Please and thanks.
Dave

 

Hi Dave,

Are you sure you know which is supply and which is return?

Supply is off the top of the boiler, return on the bottom...

Can't dig in now, sack time...

Can you take pictures all around of you boiler so we can see what valves and such that you have?

Read this:

http://www.doityourself.com/forum/bo...ure-gauge.html

and this, because at some point you will need to know:

http://www.doityourself.com/forum/bo...sion-tank.html

 

Can you tell us what make and model circulating pump you have?

 

Dave.....snuck in here and reformatted your text. It's very hard to read as one paragraph.
You're in good hands with Trooper.

 

Just a quick note before seeing the pics.

NEVER, NEVER EVER bleed the system with the PUMP on.
You can, and should, do it with a warm boiler.
Not a HOT boiler, as you can shock a cast iron boiler with a bunch of cold incoming fresh water.

 

First off, thank you for the fast replies! Itfeels good waking up to it.

TOHeating, I will take your advice and never do that again.

Trooper, I am 100% that I have identified the correct lines. Also, I want to add that I checked the expansion tank and it's hollow at the bottom and full at the top. A air pressure gauge reads 13 psi.

Link to pics in next message.

Once again thanks for your time!

 

Ohh, and the circulator pump is a Taco 007-F5

 

I'm sorry just checked my post and the link was copied wrong. Here are the pics:

http://s1297.photobucket.com/user/da...bile%20Uploads

 

Here we go again with the 'tap test'... it is a internet superstitious wive's tale that tapping an expansion tank will yield any useful information about the condition of an expansion tank. Just put it out of your head.

When you read the pressure of 13 PSI on the tank, what is the pressure on the boiler?

If there is ANY pressure on the boiler side of that tank you will NOT get an accurate read of the pressure in the expansion tank.

I will study your pictures in a while...

 

Not at home right now, but when I read pressure off the expansion tank. The boiler pressure was about 18-20 psi. I will do exactly what you posted earlier about the proper way in checking the expansion tank. Once I have my reading I will post it.

 

I strongly suspect that your boiler gauge is lying, and that you don't have much pressure in the boiler.

Additionally it sounds as if you may also possibly have a problem with the circulator not running.

 

Davie, don't obsess over the tank. If it was installed last year, I'm sure it's still got enough air in it. That's something that you need to keep in mind for NEXT year, maybe pump a little air in if it needs it.

Your problem is somewhere else, the tank won't cause 'hammering'.

I think the first thing you need to know is if your pressure gauge is accurate.

The fact that you say it sits at 20 all the time and maybe 'shakes' a little... that's telling me the gauge is kaput.

If the pressure in the system is low you'll never get all the air out.

 

Okay. I also got some advice from a mechanical engineer at work. He said it sounds like the circulator pump is shot and that I should replace it. Only question I have about that is how could I test if it is functioning or not? I would hate to replace it and have the same issue after replacing it.

Also when I had my auto fill valve, expansion tank and relief valve changed out the plumber replaced my temp gauge as well. Could the gauge really go bad after 1 year?

 

I would hope not, but stranger things have happened.

How accurate do you feel that the tire pressure gauge you put on the air valve on your expansion tank is?

I ask this, and doubt your pressure gauge because:

If you had say 20 PSI on the water side of that tank, you should have also measured 20 PSI with your tire gauge on the air side of the tank. You should be seeing whichever of the two pressures is GREATER.

One or both of the gauges are wrong... but which one?


Changing a pump isn't too terribly difficult, but you may have to drain the boiler to do so.

You have a bunch of valves that you can close to isolate much of the system but I can't see everything in the pics so can't really advise completely...

In this picture, the "LEGEND" valve looks like it feeds one of your heating loops, and there's a pipe leading to the right, out of the pic. Is there also a valve on that pipe?

 

Yes I have another legend valve that is on the other supply line.

Check this out Trooper, I went out of state (Massachusetts) to visit my mother and before leaving set the tstats at 72* just so I would hope that I could come home to a warm home and guess what? All my radiators are nicely heated my tstat reads 72* as well!!? My home is toasty now.. What is up with that?

I also have a pic with the temp gauge if you want to see it. The boiler just finished firing and reading at about180*-190* with pressure at about 22 psi. This usually happens after I bleed the system but this time I didn't touch it. I last bled yesterday before posting on here. Would that still indicate a bad circulator pump?

 

I also want to add that I've been monitoring the boiler since I came back home and the boiler has fired 3 times in anout i dont know 10- 15 minutes when the tstats are reading that the room is up to temp... I'm confused. Have you ever seen this happen?

 

This was like months ago, right? You aren't saying that this is the first time you've turned the system on this winter, are you?

What sometimes happens with wet rotor pumps (such as yours) is that when they sit over the summer they 'stick' and don't want to start again.

If this was the first time you've turned it on this winter (I find that hard to believe!) then this MAY have been what happened.

Maybe...

Just guessing at a possible reason...

And if it was not the first time this winter that it's been run, it MAY happen again...

It does appear that you have valves which would allow you to isolate the boiler from the system so you would not have to drain the entire system, only the boiler, and only about half of the boiler, in order to change the pump if it becomes necessary.

 

Digital stats? You can't see the decimal places...

Does the display indicate that the stat is calling for heat?

 

Yes it was a little while ago. The tstats do not appear to indicate when calling for heat and they are digital.

 

There's no little "flame" icon?

What make/model are the t'stats?

 

It says LUXPRO. Don't see a model number. I haven't noticed a flame icon.

 

On my LUX the word "HEAT" flashes when there is a heat call. I assume yours is probably the same. On no call, it just stays, no flashing.

 

OK I haven't taken notice. It was late last night and I passed out. Right now I'm at work.

NJ Trooper, are you thinking that my pump is still the issue. I believe so. Should I buy and replace that?

 

I'm not saying anything definite... of course I can't because I'm not there.

Just saying that these pumps occasionally do 'stick'. Often, once they are moving again they are fine for the season.

Whether or not you replace it depends on your 'comfort zone' I suppose.

 

Well after work I stopped at Home Depot and bought the pump. Installation was fairly quick and easy. I will make another post if I have any issues.

Thank you so much for your time and help!!