Help understanding boiler system

marto

hi all, just moved into a house with a boiler system. Trying to understand what all the valves are. I just turned on the system for the first time but it does not seem to be heating very well. Can someone please help me try to understand this a little better. Should the three valves be open or closed in the third picture? What are those for? What about the valve in the last pic? Thank you!

LRCCBJ

The three valves that are partially closed are used to slow the flow rate a bit. Apparently, the installer had a bit too much flow and decided to throttle the three zones to increase the Delta T between the supply and return. Just leave them as is unless you thoroughly understand WHY they are throttled slightly.

The question that begs is why you believe the system is not heating well? Do you have cast iron radiators or finned tube baseboard?

What is the temperature on the single gauge at the moment you believe the system is not heating well? How much time has elapsed between the start of the boiler and the point where you believe the system is not heating well?

Is the boiler still running at the point where you believe the system is not heating well?

What is the thermostat setting and what is the room temperature at the point where you believe the system is not heating well?

marto

hi thanks for the reply. I have finned tube baseboard. The temperature outside is about 50 degrees, when I turned on the system the thermostat inside the house was reading 57. After two hours the temperature got up to 59. The baseboards felt warm to the touch but not hot at all. I am not sure if this is the way it’s suppose to be? I am new to this type of system. Should the baseboards get hot to the touch? Shouldn’t the system heat up the house faster since it’s not even cold outside?

pecmsg

the boiler appears to have outdoor reset. Meaning it’s going to lower the supply water temperature when it’s mild outside.

One or 2° an hour is really a good rise

Try opening those three valves all the way. Ball valves are not designed as balancing valves.

LRCCBJ

https://forum.heatinghelp.com/discussion/comment/1814118#Comment_1814118

Please answer the questions posed.

What is the temperature on the gauge on the piping near the boiler?

Is the boiler running for the entire period that you are attempting warm the room?

When you turned on the system, what was the setpoint on the thermostat?

marto

here the pics of the two gauges. First pic is the gauge on the boiler unit. Second gauge is on the piping. The boiler cycles on for about 5 min every 25 min or so. Set point on thermostat is 70 degrees. I looked at the gauge on the piping after turning the unit off and it seems that it has not moved even after turning the system has been off for a while.

marto

Boiler now just cycled on for two minutes

bburd

Almost certainly your system has outdoor reset, which is wonderful at keeping a building comfortable at a steady temperature. The supply water temperature to the radiators is adjusted based on how cold it is outside. It should be set up to just offset the building heat loss.

Usually there is a boost function that will raise the supply water temperature if there's a significant difference between the room temperature and the thermostat set point, or a long continuous call for heat. This may not be working in your system.

Can you find out who installed or has been servicing the system?

LRCCBJ

Yes, as mentioned above, you certainly have what we refer to as "outdoor reset". The computer reduces the boiler temperature based upon the outdoor temperature. If it is 50F outside, you certainly do not need 180F water to heat the building. You might need 180F when it is 0F outside.

The downside to this system is what you have observed. If you have a significant "setback"………….in your case over 10F, the system doesn't know that and it will still provide the same 150F supply water. This is not very significant for energy delivery and it will take "forever" to get to 70F. This is normal.

Such a system needs to be utilized with MINIMAL "setback" . If you want 70F in the room, you cannot let the room go below 65F………..or you will wait forever…………..for it to return to 70F.

In your current situation, you'll need to be patient for eight hours or so for the room to make 70F. Then, leave it close to 70F (no less than 65F) so that you have a reasonable "recovery" time. Or use a programmable thermostat and start the program three hours ahead of the point where you want 70F. If you want 70F at 8:00 am, set the stat to 70F at 5:00 am. These times are not a certainty. It all depends on how the unit is programmed. If you are getting a 2F increase per hour, you'll be perfectly fine. Some systems, if setup perfectly near the limit, will only climb .5F per hour…………or might not climb at all in the case of a well setup mod-con boiler (which you do not have).

neilc

can you tell if the circulators are running?

feeling with your hand, carefully, is there heat before and after each circ? or past the zone valves?

are the manual levers under the zone actuators free swinging, or is there resistance?

how about at the 3 1/2 closed valves?

batteries fresh in the thermostat(s)?

boiler is making heat, but it's not getting around

marto

That all makes sense about the outdoor reset thanks for the replies! unfortunately I have no information as to who serviced or installed the boiler. This house was purchased as is with no information on anything. All I know is the boiler was installed in 2017 and the previous owner was an engineer so maybe he did the install? I see no stickers or labels near the boiler or servicing records. How often should the boiler be serviced? Do they get like a tune up of some sort?
There are still three baseboards that have not been installed. They just never installed them I found them in a closet. Two small ones 3 ft for the bathroom and one for the kitchen and one larger one for the dining room. Could this be the reason those three valves are partially closed? Or that has nothing to do with it? Im assuming the system is oversized for the amount of baseboards currently in operation. Would this damage the system in any way? Thanks all for the responses they have been very helpful so far.

pecmsg

somewhere on the unit it’s a tag showing the manufacturer the model the serial number. go to the web and find a service providers in your area

HVACNUT

Lift the cover and see if there's an outdoor reset option card. Or it's possible it's wired into the aquastat. You should have the manuals. Download if needed. With fin tube baseboard, having all the returns throttled down is a little weird.

An oil fired boiler needs annual maintenance with the tech leaving a combustion report assuring a clean bill of health.

EdTheHeaterMan

There is a black plastic cover on the top front that hides the controls where the Red Arrow is pointing.

The Option Card for Outdoor reset is located where the Green arrow is pointing. That control has 3 spaces for option cards. You want to see if there is an "Outdoor Reset Card" like this:

Knowing that this option card is in place will determine how to get your boiler to heat your home faster. If you do not have that option card, then the Boiler Control on the left is determining the boiler temperature limit. Knowing if that option card is there will determine what to do about your situation.

EdTheHeaterMan

The company that sells you fuel oil can help you find a service and repair provider. If they have employees that do it, or if they recommend an independent service company. They know someone that can get you operating properly.

EdTheHeaterMan

Here is what I can tell from the photos you posted.

You have 3 zones. One zone is priority for DHW and they should be connected by piping and electrically as described in the I/O manual for priority using the green circulator pump. With a proper FloCheck valve in place, the zone valve below the green circulator is not necessary. If there is no FloCheck for that zone, then the Zone Valve is an expensive Check Valve.

The other two zones are connected to by way of zone valves to a ZVC control that also operates the central heating circulator pump when one or both of the valves are open on a call for heat from a thermostat. The Central Heat Circulator is the black one. When there is a call for heat from the water heater, the central heat circulator will stop operating, the boiler temperature will go up th the boiler control high limit and put all that energy into the water heater (so you don't end up with a cold shower)

Some notes.  

1. The temperature gauge on the pipe will not offer you an accurate water temperature,  close but not accurate.  That is because the sensor portion of the thermometer is about 3 inches above the water that you want to measure the temperature of.  It may be as much as 15°F high or low depending on what is happening to the water in the pipe below. Is it increasing in temperature? Is it decreasing in temperature? 
2. The bracket and ½” copper that is holding the expansion tank in place may not be enough to handle all the weight of the tank iif that tank is full of water. I know that the tank should never be full of water BUT when it fails, it may become full of water and that may bend the copper pipe to a point of failure and perhaps a water leak. And you know that will only happen when you are on vacation so you come home to a flooded boiler room.
3. The water heater Pressure Relief Valve should have a discharge pipe added to vent any water to a floor drain or to within 6” from the floor
4. The BackFlo Preventer has a vent at the bottom that should have a discharge pipe added to vent any water to a floor drain or to within 6” from the floor
5. Check the boiler relief valve, I can't see that being any different than the water heater PRV and the BFP
6. The 3 blue handle valves on the return piping have no business being partially closed.  Open them to full

marto

thank you so much for the very detailed response! I really appreciate it. I now have a pretty good understanding of the system and you answered all my questions!

SuperTech

"previous owner was an engineer"

That actually explains a lot. You really have a great looking setup that was nicely installed. The only drawback is that it is more sophisticated than the majority of the boiler installations that are out there. You may have problems with finding a technician who is familiar with your setup and full understands everything you have. The previous owner likely took care of the maintenance as well.

Do everything you can to learn about your boiler so you can understand how it works. If you find a good tech who knows the system, great. If not you might have to help your service provider when issues arise. The burner itself should be easy enough for the average tech to understand.

marto

I have one last question. Could the reason that the three return valves were partially closed be that there are still three remaining baseboards to be installed or there is no reasoning behind this thought? I’m just trying to understand why the previous owner would have left the three return valves like this. Seems like he used the system that way.