Central Boiler steam leaking from top, temperature won't drop

[jaycmw18]

Is there a pressure gauge and temp gauge on your oil boiler? If so what are the readings ?

There is no pressure gauge or temp gauge on the oil boiler side

 

[jaycmw18]

According to central boiler, your hi limit setting for your model boiler should be 185° or above. I would check to see what your max setting should be for the PEX pipe you used and adjust accordingly. Had your OWB been running normal before this incident? My basic theory is when all else fails, go back to the beginning and start over. Is your temp gauge reading 210° or is that the setting you have chosen for it ? Try resetting your basic thermostat settings and see what happens. Is there still steam coming out of the top of the boiler? I see in the Central Boiler info package that they refer to the systems as pressurized or non pressurized. Pressurized would be the closed system and non-pressurized would be the open system. Do you recall which one you have?

Yes, my OWB had been running normal. I typically run the OWB at 190, I tried to lower it to 180 with no change in behavior. Steam has been steadily coming out of the top for two days now although it has been slowing down the last 8-12 hours.

 

[jaycmw18]

It appears as though it is a non-pressurized system

 

[djones]

Before replacing any more parts, you have to find out if you have any flow to the house from the OWB. I am assuming that you have a fire going in the OWB and that the temp you are reading is the actual water temp. How hot are the pipes at the pump on the OWB ? Check both sides. Then check the temp on the pipes at the heat exchanger. According to the picture you posted and the diagram from central boiler, you should have a fairly consistent temp across those points of reference. With your pump being located close to the OWB, the temps are going to (should) be high on both sides even if the pump is not running and you should have similar temps at the exchanger, minus some loss due to distance from the house. But in both cases, if the pump is working correctly, you will have hot water at the exchanger. If the exchanger has one side hot and not the other, then the exchanger may be the problem. Have you tried just using the oil boiler to see if it heats the exchanger also? The way that it is plumbed in, it should heat up the exchanger when running the oil boiler. Looking at your picture, how hot are the pipes on each side of the oil boiler circulator, before turning on the oil boiler? After?

 

[NSMaple1]

Unless the boiler temps are wonky (and if there is steam flying, they shouldn't be) - it seems pretty obvious there's a flow problem. That should be easy to determine - if the OWB pipes in the basement aren't too hot to touch, the water isn't flowing. If the HX is blocked, it shouldn't be hot on either side - if water isn't moving, heat isn't getting to it either. A partial blockage, or sick but not dead pump, might show hotter on one side of the HX than the other. Is the OWB circ making any noise at all? You might have to get your ear right up to it. A hum might indicate a stuck circ or wonky motor - gurgly type noises might indicate cavitation/deadheading from a HX blockage. No noise at all might indicate it's dead. Either way, with no isolation valves, it will be a PITA, I'm afraid.

 

[NSMaple1]

Just went back & saw your HX pics.

Some troubleshooting info, assuming the OWB is higher than the HX:

Shut off your OWB circulator. If you close both isolation valves on the OWB side of the hx, then crack/disconnect the union for the OWB return line (a little water will spill out, but should just be what's in the HX between the valves), then crack open just a bit the isolation valve for the OWB supply line, water should run out the open connection fairly freely. That should mean that the HX isn't obstructed.

If the OWB isn't higher or there isn't much difference, and you don't get a gush - turn the OWB circ on for a moment. That should push water out if there is no HX blockage. And if your circ is working.

That won't shoot all your troubles, but should shed some light. If the HX is plugged, it will at least require a good flushing with maybe something like muriatic acid (others might have better ideas on that). If it's plugged too bad, might be better off just swapping in a new one, then work at cleaning the old one up when you have time for use as a spare.

If the HX seems all clear, I think I would just get a new circ & do the swap anyway - at 10 years old, you should have a spare, if that doesn't fix it.

Or, you could wait for your dealer guy to help.

 

[djones]

Good plan. Lets hope that the OWB is higher since he seems to have an open system. If installing a new circulator is what needs to be done, now would be the time to think about putting in isolation valves as well.

 

[jaycmw18]

I powered everything off for about 2 hours and just powered it back on. I noticed when I had this all turned off, my house was actually warm again thanks to the oil heat.

Attached are a few additional pics. I labeled my plumping on the house pipes as well. This is all after turning on the wood boiler and waiting about 30 minutes. I'll now turn it off and post what the pipes feel like on just the oil burner

Pipe 1 is hot beneath the yellow handle, and slowly gets hot to warm as you follow the pipe outside
Pipe 2 is hot beneath the yellow handle, but room temp as you follow it outside
Pipes 3 and 4 are both hot to the touch

All pipes outside in my OWB are hot to the touch

 

[jaycmw18]

Just went back & saw your HX pics.

Some troubleshooting info, assuming the OWB is higher than the HX:

Shut off your OWB circulator. If you close both isolation valves on the OWB side of the hx, then crack/disconnect the union for the OWB return line (a little water will spill out, but should just be what's in the HX between the valves), then crack open just a bit the isolation valve for the OWB supply line, water should run out the open connection fairly freely. That should mean that the HX isn't obstructed.

If the OWB isn't higher or there isn't much difference, and you don't get a gush - turn the OWB circ on for a moment. That should push water out if there is no HX blockage. And if your circ is working.

That won't shoot all your troubles, but should shed some light. If the HX is plugged, it will at least require a good flushing with maybe something like muriatic acid (others might have better ideas on that). If it's plugged too bad, might be better off just swapping in a new one, then work at cleaning the old one up when you have time for use as a spare.

If the HX seems all clear, I think I would just get a new circ & do the swap anyway - at 10 years old, you should have a spare, if that doesn't fix it.

Or, you could wait for your dealer guy to help.

I'm not quite following the crack/disconnect the union part of what you'd like me to try. Do you mean just slightly open the valves on the return lines into the HX? Or do you mean physically open up the pipe/disconnect it from the HX?

My OWB is higher than the HX

 

[Andy-H]

I'm not quite following the crack/disconnect the union part of what you'd like me to try. Do you mean just slightly open the valves on the return lines into the HX? Or do you mean physically open up the pipe/disconnect it from the HX?

My OWB is higher than the HX

Sounds like circulation pump on stove is not moving water. Close valves next to outside pump, unplug electric, remove motor housing, I think the bolts are 7/16" head. Check impeller for breakage/blockage. You can't hurt anything in there. If impeller is broke you can get a "cartridge" for pump to fix it. Ten years is a long time on the impeller. You got your moneys worth out of it

 

[djones]

So , how hot is the pipe coming out of the pump at the boiler ? You may have to slide some insulation out of the way to get a foot or so away from the pump.
NSMaple was referring to the unions on the HX, #'s 1 & 2. Turn off the OWB , if you do not know which line is the return then you may have to do the procedure twice. Close both valves, disconnect one union, a small amount of water will come out, open the valve on the still connected line a little to see if water comes out the HX, if water comes out fairly fast then the HX should be fine. Close that valve. Turn on the OWB, the pump will now dead head, open one valve a little to see if pressurized water comes out, put a bucket under the line. If nothing comes out of the fist one then close that valve and try the other one. Be careful of the one still connected to the HX since it points up. Put a bucket over top of it and then open the valve a little. If the lines are under pressure it should squirt out pretty good. With the pump turned off you will get gravity flow because of the higher elevation of the OWB but with the pump turned on it should squirt. BE CAREFUL with the hot water.

 

[NSMaple1]

I'm not quite following the crack/disconnect the union part of what you'd like me to try. Do you mean just slightly open the valves on the return lines into the HX? Or do you mean physically open up the pipe/disconnect it from the HX?

My OWB is higher than the HX

Do you know what a union is?

 

[jaycmw18]

The pipes out at the boiler, all 3, are hot to the touch. It looks like all but one pipe gets hot to the touch, so possibly a clog in the heat exchanger or the pump inside near my furnace.

I do know what a union is now, after googling it! I'm not a plumber I think some of these troubleshooting techniques are beyond my capabilities. I've gotten into this stuff before and caused more harm than good. I do thank you all for getting me this far, I at least think it's narrowed down to one or two things. I'm hoping my local dealer will have someone available who can come out and fix this for me.

I'll post back and let you all know what ended up fixing my condition. I appreciate all the help!

 

[hanniedog]

A smart man is one that knows his limitations. No dishonor in getting help. Hoping for an easy fix.

 

[sam s]

I'm thinking its the pump.

 

[lindnova]

Yep, get a rebuild kit or a new pump. Looks like a fast swap with that setup. Still could have restriction on the exchanger. If in doubt might be best to get a dealer or plumber in there. You have isolation valves in the right places.

I can't tell the pump number but mine is a Taco 011 and am on rebuilt pump number 3 in 10 years, so pump is very likely the problem.

Also do you test your water? Poor water quality can affect HX clogging problems.

 

[NSMaple1]

Yep, get a rebuild kit or a new pump. Looks like a fast swap with that setup. Still could have restriction on the exchanger. If in doubt might be best to get a dealer or plumber in there. You have isolation valves in the right places.

I can't tell the pump number but mine is a Taco 011 and am on rebuilt pump number 3 in 10 years, so pump is very likely the problem.

Also do you test your water? Poor water quality can affect HX clogging problems.

Ya, you're right. I hadn't looked at the second pic before - looks like there are iso valves there. In that case, I'd just get a new pump & do the swap. Pretty well mandatory to have a spare one on-hand anyway. New flange gaskets while at it.

Maybe the boiler guy got out there & has it done already by now - but at 10 years, I'd be just as leery of buildup in the HX as I would be of the pump. It should likely be flushed anyway.

Curiosity....

 

[farmer steve]

following the thread just because i might need this info some some day. thanks to @NSMaple1 AND @djones and the rest for helping out a fellow keystoner.

 

[farmer steve]

The pipes out at the boiler, all 3, are hot to the touch. It looks like all but one pipe gets hot to the touch, so possibly a clog in the heat exchanger or the pump inside near my furnace.

I do know what a union is now, after googling it! I'm not a plumber I think some of these troubleshooting techniques are beyond my capabilities. I've gotten into this stuff before and caused more harm than good. I do thank you all for getting me this far, I at least think it's narrowed down to one or two things. I'm hoping my local dealer will have someone available who can come out and fix this for me.

I'll post back and let you all know what ended up fixing my condition. I appreciate all the help!

hope you get up and running @jaycmw18. where in PA are you? york co here.

 

[jaycmw18]

I'm having someone come out today from Lawn Care Distributors where I bought the CB from (http://www.lawncaredistributors.com). I brought him up to date with the knowledge that was shared here and he believes as well it's either the pump or HX but leaning more towards the pump. I'll shadow him today just to build my own confidence in servicing this thing in the future should this happen again - and keep a spare pump on hand. I have a spare solenoid, temp controller/probe so might as well have the Taco 009 on-hand also.

I do test the water, maybe not as regularly as I should but last time I did was last summer. Before that, maybe 4-5 years prior was last time I checked it.
I am in the York County area as well.