Loss of pressure

photokynetics

I have an aqua balance combination boiler, and the feed pressure was right around 14 or 15 psi then it dropped to about 8 psi when I caught it and then it went right to zero, code 37 appears, there are no signs of water leaking anywhere. I don't know how to add water pressure to this boiler to bring it back up but while I was playing with it the pressure came up by itself and the boiler worked fine then after about an hour it lost pressure went right back to zero. What could cause this?

Jamie Hall

Sorry, but somewhere there is a leak. The only way that system pressure in a closed system can drop is a leak... it came back up most likely because you have an autofeeder which woke up and did its thing.

dko

So many unconventional piping and fittings on this install.. but everything is labeled at least??

photokynetics

We just bought this home two months ago and when I looked at this heating system my request that the seller at least label where everything goes, but I've never owned one of these things so I don't know how you top off the boiler feed water or whatever it's called. I've read that it's got many different names but all I know is the pressure goes to zero and I've looked everywhere for any leaks and I can't see anything, is there a possibility that there's an internal leak somewhere or maybe whatever feeds this gauge is going bad? Do these systems have an automatic filling feature? At the top on the right side of this regulator looking device there's a little blue line that says boiler makeup DWS, does this boiler get its feed water filled from this hose? If so, how?

hot_rod

At the very top of the pic is the automatic fill system intended to maintain 12 psi or so. Looks like it is labeled. If you can shut the system completely off for an hour or so, with that blue handle valve shut off (no fill possible) then monitor pressure It may drop a psi or so as the water cools, but can only go to zero if there is a leak.

Any underslab radiant? That is often where undetected leaks are.

dko

Quick question,
Has this worked before and this issue is happening just recently?

Can we get clearer photo of this portion so relief valve drain pipe is not blocking the view of that tee? Curious tee if it indeed is a tee. Arrows facing opposite ways at that tee junction and then connected to bottom of buffer tank?



And another photo backed away a little so can see the overall, including where the heating side expansion tank is- as it is not in your picture.

edit: nvm I see another tee fitting at the buffer tank connecting the expansion tank and relief valve. I'm pretty sure that's a potable water tank. But seeing as you labeled the boiler buffer tank "thermal tank" might have had the wrong idea. But should be fine if you adjusted the psi and not left it factory, I see some markings.

I'm getting more confused the more I look at it. More pictures can help

Also, where is the condensate draining into? what kind of pipe or area? I don't see a neutralizer.

edit2: just read the part you bought the house 2 months ago. was it a new build? I recommend getting a professional in to look at this frankenstein.

109A_5

Hello @photokynetics,
I would say the fill valve is this Black handled valve and it looks closed (no water flow).
I suspect the Blue handled valve is for minimal system water loss during filter changes.

SgtMaj

Possible expansion tank failure? Or maybe leaking heat exchanger? Look for water coming out of condensate drain without the unit running. Otherwise you’ve got a leak somewhere in the system. Call a local professional to troubleshoot. Additionally, what’s marked as a thermal storage buffer tank looks like an iron air compressor tank. That system was not designed nor installed by a professional. Not sure why you have a combi boiler when it looks as though you have a gas fired water heater. Good luck.

photokynetics

Here are a couple of more photos I don't know that he designed this following any specifics I asked him about all this plumbing and he said he kind of put it together how he thought it should be but I don't remember him telling me that you don't have to fill it with water because it will fill automatically he wrote on the door that you have to keep the pressure to a certain point but I don't remember him ever saying how. This system Heats radiators in the walls is all it does 

JUGHNE

What type of emitters (radiators, baseboard convectors, fan coils in an air handler, tubing in the floor etc) do you have?

Is that a "Baldwin" spin on filter at the top?

Someone really cleaned out the parts bin/truck for this one.

photokynetics

That little black valve up on the top by what looks like a regulator I have turned that valve either direction while watching the pressure gauge and it doesn't seem to make a difference, you can't hear anything flowing.  these are the type of heat exchangers or radiators

EBEBRATT-Ed

It could very well be an expansion tank problem especially if you have fluctuating pressures you are having. You have to remove the expansion tank or isolate it and remove the water pressure from the water side and then check the air pressure on the air side of the tank. Should be 15psi.

dko

Edit

109A_5

Hello @photokynetics,
Can you get water from here ? Is the cold water shut off somewhere upstream ?

photokynetics

You can get water from that valve you inquired about. I have turned every valve possible reluctantly to no avail

photokynetics

I have opened that valve and you can get water, it's cold, the system was working just fine up until 2 days ago when that pressure went from 13 or 14 down to eight and then to 0

JUGHNE

Your last picture is a filter grill over the top of a coil, which could be either for heating or AC.

You need someone to go over everything mechanical in this house and explain everything to you.
Record their explanations for future reference.

Did someone pay for an inspection of some sort?

photokynetics

I paid for the inspection but the inspector was very confused cuz he's never seen anything designed quite like this but he said it seems to be working and the building inspector put his label on it so my home inspector said it should be fine. 
If I could find out how that pressure is increased or decreased whether it's manual or automatic that would help me to troubleshoot this

109A_5

Hello @photokynetics,
With the black handled valve open, have you lifted the handle on the regulator briefly to see if that give you some water flow? As was previously mentioned maybe the regulator is intermittently stuck shut.

photokynetics

The coils are for heat only

SgtMaj

What is your background?
If your an engineer gear head type or know your way around a tool box, you should have no issue figuring this out. Follow the blue line from the autofill valve there should be a shutoff somewhere which is preventing the water from flowing.

There’s a whole lot in there that shouldn’t be, Did the system ever work? I’ve got a million questions that can’t be answered here.

Are there no hydronic professionals in your area? Or even a master plumber that can walk through that piping?

Where are you located?

JUGHNE

With the black lever open (parallel with the pipe) try exercising the lever on the fill valve several times.

They will stick sometimes and that may free it up internally.

If water flows, do not leave it in the up position or it will over pressurize the system and the relief valve should open at 30 PSI.

photokynetics

I am mechanically inclined, an electronics technician but I've never worked on a boiler system. I've been told this one is more complicated than it should be, that automatic fill valve you're referring to I thought was just a pressure regulator, I've never seen one like that either, i've turned that handle on it but I thought all it was was a lockdown for the adjustment. 
Like I said before this thing was working flawlessly until 3 days ago. That blue pipe that is labeled boiler makeup water has a shut-off valve right next to the boiler itself it is currently in the on position.

photokynetics

That blue line turns down to the side of the boiler there is a shut-off valve which is in the open position and then that line runs up under the pump and ties in right above where that drain valve is

photokynetics

I was able to figure out how to pressurize this tank I'm pretty sure now it is going to fire up but I've obviously got another problem somewhere that's making this pressure leak down. But like I said, I have not seen any liquid leaking anywhere.

photokynetics

photokynetics

This is where the boiler makeup feed connects to for water

photokynetics

photokynetics

photokynetics

This valve previously inquired about just opens up at the end of the pipe, I imagine for future additions,  it's a part of the recirculation Loop for the hot water

SgtMaj

@photokynetics Remove the flexible condensate line and see if the heat exchanger is leaking.

SgtMaj

@photokynetics how long has this system been installed? If there is air in the system and it’s slowly making its way out though that air vent on top of that tank hanging on the wall you can get a pressure drop when the pump starts moving the air and the water and the air makes its way to the air vent. But if the water fill valves are on it should stay at a constant pressure. Is there an air vent somewhere else in the house? If there is another air vent have you checked it to see if it’s leaking? How long does it take for the pressure to drop? Check to make sure your relief valve isn’t leaking.

photokynetics

I'm not sure how long the system's been in place I'm assuming only sometime in the last four or five years, it was working great up until a couple of days ago it takes about two two and a half hours to go from 16 PSI to 0. I can see no water leaking. I will check the condensation drain and see.
How much liquid is involved with a psi loss of 18 psi in these systems?

Jamie Hall

The amount of liquid is dependent on the size and precharge of the expansion tank. The amount from any given pressure down to the precharge pressure can be significant -- as much as a gallon or so, or if it is a big tank even more. However, from the precharge down to zero the amount will be very small -- less than a cup, if that.

photokynetics

It's possible then I could have a leak and have it be very difficult to detect?
I've got a person coming out tomorrow to help me find the problem.

Jamie Hall

Indeed so...

photokynetics

I had a specialist come out who, for as young as he is knows a lot about boiler systems and in a couple of hours he was able to isolate and fix the problem, apparently it had a bunch of air in the system he suspects from when it was winterized never got completely bled out, then up top he opened up the fresh water valve, suggested leaving it open, messed with the regulator a little bit but he said this auto feed Air Relief on the top of the tank was stuck, it's supposed to automatically bleed the air out and then add water to the system as it's needed, he recommended moving the air bleeder valve on top of that tank where the elbow is so that it's the highest point of this monstrosity, he's fairly confident it should work quite decently now but he recommended putting in a flow meter between the regulator and the preventer valve, I like that idea cuz it will enable me to keep an eye on the actual water usage and detect the problem before it becomes a big issue.
Thanks to everyone's help I understand this system quite a bit better now thanks to you guys.

hot_rod

I'm not liking that air vent installation. It needs to be level or the small float inside can rub and hang up on the side. Which may prevent it from ever allowing the air out.

A Caleffi 5026 is an auto float vent where the float rides on a pin up through the center so the float doesn't hang up when it is not exactly level.

If air problems return, two brass 1/8: street ells could get the vent you have level. Or a 5026, but they are only 1/2 or 3/4"

You have a isolation valve to easily install two street ells.

Shown below are the two types of auto float vents, with or without the center pin.

photokynetics

photokynetics

He removed the air float valve and took it apart, the inners look just like the ones you sent. He recommended removing the elbow from the reservoir tank and replacing it with an elbow with a 1/4 inch hole to relocate the air valve to the higher point.

hot_rod

What exactly is that tank supposed to be doing? It has PVC attached to it, a paper oil filter canister?
The system really needs a good air purger for adequate air removal. That vent only grabs what gets stuck at the top of the tank. Any vents up higher in the building?

Is there a piping schematic to determine what is going on in all that piping?

Since you have a mini ball valve already there, the two 1/8 or 1/4 street ells would not require draining the system to repipe in a tee? Something like this. But with two NPT street ells. Thats something you could do with a trip to the hardware or box store.

Here is the Home Depot part #