New house with solar/propane boiler/pex radiant = confusion

cms829

I'll try and make a long story short. So we moved in this house in June. Previous owner own a solar/alternative energy company and installed both solar electric and heat. We are in upstate NY, which is always cloudy this time of year so the solar isnt doing much in the way of heating except preheating our DHW.

It is 6 zones controlled by an Argo ARM-6P. Is anyone here familiar with that relay switch that could help me understand it a bit more? I dont think things are really functioning properly. IE: Zone 1 light comes on...and the circulator pump is running. But that zone valve isnt opening.

Also - according to the boiler, while some of the zones are open and flowing - the supply and return water and mostly the same temp. Considering this is a condensing boiler, dont I want the return temp much lower?

Excuse me if they seem like routine questions - but coming from cast radiator steam heat this is like operating a space ship.

hot_rod

You will need a volt meter to start checking where you do or do not have power. Is there power at the zone valve when that zone is calling? is there power at the terminals that connect that zone valve.

Was a wiring schematic left on the job showing how the entire system is controlled and wired?

Wiring schematics for the individual components?

cms829

Thanks for the quick reply!

Disregard...I figured out the circ pump/zone valve issue. So the left most circ pump in the pic....apparently comes back to the right most zone valve/return line. And vise versa. All the others are in line. But those two are opposites for some reason. I saw he had labeled the pex itself with a faded marker.

So that seems to be solved. What about the supply/return temps on the boiler? Shouldnt the return water be cooler? At least thats my understanding that its better for a condensing boiler.

hot_rod

The temperature in the distribution will move a bit. you may see a larger temperature difference on a cold start, temperatures may be within a few degrees when it meets set point. Radiant zones could be designed around a tight 10 delta

cms829

Ok, so I'll just forget about that for now. I was looking at some of the parameters on the boiler, and he has the following. I assume he has the max operation set point low to preserve propane? Who the heck knows. I am wondering if maybe that should be brought up? Right now the temp measured via Infared at the manifolds is rarely over 103 degrees. And we seem to be using an excessive amount of propane. No leaks. But something tells me lowering the temp to conserve propane may actually do the opposite. Again - combustion check was already done by the local company. He also said I could raise it quite a bit. But I wasnt sure what is "right"

CH Maximum Boiler Operating Setpoint - 130 F
CH Minimum Boiler Operating Setpoint - 86 F
CH Reset Curve Coldest Day - -04F
CH Reset Curve Coldest Day - 64F

Thanks again for the help. I know this all propably seems silly, but its all rather complicated for me.

hot_rod

The goal would be to heat the home comfortably with the lowest possible SWT, supply water temperature.

How large of a home and how much LP consumption? Pool, garage or snow melt connected?

Make sure boiler heat isn't going to a solar buffer tank and loosing heat somehow. Typically the boiler runs directly to the heat when solar is not available.

It may take some trial and error adjusting to find that sweet spot, unless heat load calc and design was left on the job. It looks to be a well though out system. Was it Advanced Radiant Design by chance?

cms829

Unfortunately the load calc was not left. Nor were any designs of the system or layout of the loops. The manifolds arent labeled, but the zone valves are so I mostly know whats what.

Home is 2472 square feet. Well insulated but dont have specifics. Only thing on propane is the boiler, kitchen stove, and clothes dryer. Also a propane fireplace but we dont use it at all.
From 10/22/19 up to 11/22/19, we went through 175 gallons. ($385 bucks worth) Maybe its not excessive, but it seems like it. Again, I've never owned anything with propane heat.

The boiler is piped directly to the indirect hot water tank, and the heat. But to be certain I'll take some more detail pics. Negative, not Advanced Radiant Design.

hot_rod

175 gallons for a month?

5.8 gallons a day approximately?

1 gallon = 91,500 BTU.

If the boiler is a 91,000 BTU input, that would be 5 hours of run time a day.

How cold has it been, that is the biggest factor in heating fuel consumption.

Zman

As for your question on boiler delta t, what size boiler and what model/speed boiler circ? Triangle tubes have very low head loss and are often overpumped.

cms829

Sorry I probably should have specified that it is a Triangle Tube Solo 110 boiler. Think it is 87,000 BTU on propane.

It honestly has been up and down. As high as 60 some days and down into the 20s others.

Zman, the boiler circulator is on Medium. So were all of the zone circ pumps but i knocked them down to low to try and bring the return temp down and put more heat into the house. If my thinking is correct, anyway.

hot_rod

Where about in NY? Looks like there has been some single digit nights around Utica area mid November.

Good idea to make sure the system is running at peak efficiencies.

Really the heat load on the home will dictate fuel use. On the coldest days, with a properly designed and sized system, the boiler may run non stop, consuming just under 1 gallon an hour if it it ramped up to full output.

Zman

You want the boiler circ on low. It is what drives the delta t at the boiler. I have never understood why TT provides a 15-58 with that boiler, it is way oversized.

cms829

We are near clay NY just northwest of syracuse. Yea there were a few cold nights in the past month or so. Dont think we saw single digits just yet but out towards utica they did. I was hoping for a slightly lower bill i guess. Thats a lot of coin for a month. Im thinking about doing some more insulation in the attic. Just finished insulating the basement walls. They had some spray foam insulation and now theres 3" roxul over it. Next is the basement ceiling. A lot of that insulation looks like crap.

Zman, i lowered it to low and already seeing tbe delta t increase. Thanks!

hot_rod

cms829 said:

We are near clay NY just northwest of syracuse. Yea there were a few cold nights in the past month or so. Dont think we saw single digits just yet but out towards utica they did. I was hoping for a slightly lower bill i guess. Thats a lot of coin for a month. Im thinking about doing some more insulation in the attic. Just finished insulating the basement walls. They had some spray foam insulation and now theres 3" roxul over it. Next is the basement ceiling. A lot of that insulation looks like crap.



Zman, i lowered it to low and already seeing tbe delta t increase. Thanks!

Do all you can to lessen the heat load. A blower door test would show where you have air leakage, your biggest "energy stealer"
Check weatherstrip on doors and windows. All the exposed wood framing sealed well? Rim joist to sill and foundation are notorious leakage areas.

The best time, energy and $$ you can spend is tightening up the structure, that is what dictates fuel consumption. It's the gift that keeps on giving.

Assuming the boiler is adjusted and dialed in as best you can.

Check at www.dsireusa.org They often have energy programs available.

cms829

Yea, I think I am going to add to the blown in insulation in the attic. It has definitely been disturbed and is certainly not evenly distributed. I have checked all doors and windows. Everything was new in 2006 (house was built). Rim joist area has ridgid foam insulation and where possible the previous owner had spray foam installed on top of it. I am going to put some roxul into the areas that were not spray foamed.

The HVAC companies in the area can do a no cost energy audit compliments of the state. I think I am going to have one done ASAP. My issue is...I can do all the work myself. I dont need someone calling me every other day trying to sell me crap. lol.

My return temp has come down by lowering the circ pumps to low. With 3 zones running a little while ago my supply was 110 and return was 100

hot_rod

you are on the right path. older "average construction" homes often have upward if 15 air changes per hour. Energy Star certification states 4 changes or less per hour. German PassivHaus standard 0.6 !

Once you have an infiltration number, convert it to BTU/hr of heat loss.

Qi= 0.018(n) (v) (∆T)

n= number of air changes per hour
v= volume of heated space or building, in cubic feet
0.018= heat capacity of air
∆T= inside air temperature- outside air temperature

The heat input required is directly related to the heat loss of the structure, infiltration is the biggest thief of your energy dollars.

Carl is helping with the boiler efficiency, fuel dollars to useable heat energy, now work on the building efficiency.

Boiler efficiency
Distribution efficiency
Building efficiency

cms829

Thanks! I filled out the application and the state will cover $200 of the $250 fee for the energy audit. So for $50 out of pocket - well worth it! I am waiting on one of the local companies to contact me to schedule it.

Thats quite an equation. I suck at stuff like that. So I may come look for some insight once I have some numbers after the audit. I have new combustion chamber insulation/gasket and a new venturi being delivered today. So I am hoping the energy audit also includes another combustion test/adjustment.

I think I may also have to have someone balance the loops at the manifolds. first off - I cant even read the flow meters anymore. They are the glass vial type and its all dirty inside. Which also makes me think the system probably needs cleaning. All of the valves on the manifold are just fully open with the exception of one loop on the one manifold. That cant be balanced. lol.

Thank you both for your help! Its been a bit overwhelming with a pregnant uncomfortable wife.

cms829

Here are some pics of the one manifold for the secondary bedrooms. In the secon photo you can see the loop in the foreground is regulated a lot compared to all the other loops (the brass set screw).

In the last pic you can see the flow meters. Which are just all black. Even shining a flashlight from behind doesnt really allow me to see where the gauge is at. Questions - Can I replace these with a better type of gauge that I can actually see? Or can I just clean these out? I cant figure out how to do that without draining the loops though.

Regarding flushing/cleaning the system. How difficult of a job is that? Im certain I could handle it. Its just the how to that gets me.

hot_rod

Don't worry so much about the number crunching, i was trying to show the relationship. Every home and homeowner has different ideas of comfort. what we like about hydronics is the "adjustability" If you have the time to tinker you should get to an optimized system. assuming it was installed based on so calculations and reality. from the pics it looks like a thoughtful installation.

The past owners may have an idea of typical winter fuel consumption? Plenty of DD degree day info and sites to visit to get typical consumptions for your area.

cms829

past owners dont really want anything to do with the house. I've hinted to him that I was wondering about what the average winter months usage was and I didnt get an answer. I am going to take a ride to the propane companies office and see if they will share it with me. The energy audit is scheduled for this thursday. And they ask for 12 months records.

cms829

Well...was 8 degrees last night. Woke up and all thermostats are a couple degrees colder than set. We have outdoor reset....but without a great understanding of it not sure if that should compensate. Settings were left as the previous owner put them.

Also been going around and found a bunch of exterior wall outlets and switches that had cold air trickling in. Going to caulk between the sheetrock and electrical box and I put the outlet insulation foam in. I guess every little bit will help.

Looking forward to the energy audit today. Was also wondering if it is possible to do a heat loss calc on an existing house?

hot_rod

cms829 said:

Here are some pics of the one manifold for the secondary bedrooms. In the secon photo you can see the loop in the foreground is regulated a lot compared to all the other loops (the brass set screw).

In the last pic you can see the flow meters. Which are just all black. Even shining a flashlight from behind doesnt really allow me to see where the gauge is at. Questions - Can I replace these with a better type of gauge that I can actually see? Or can I just clean these out? I cant figure out how to do that without draining the loops though.

Regarding flushing/cleaning the system. How difficult of a job is that? Im certain I could handle it. Its just the how to that gets me.

Looks like a Warmrite/ Kitec tube system.

It's tough to keep those windows completely clean. You could run a cleaner in the system and flush to see if that helps. But putting fresh water into the system will just cause rust or corrosion of any ferrous metals and cloud the windows again. Seems they are visible for the first month or so.

Looks like at least one zone is turned off, by the position of the allen bolt.
The branches can be turned off with the white caps or the screws on the other manifold.

cms829

Yea, I went ahead and opened that branch. It is the bedroom which is now my office (which has the thermostat in it). So maybe they were trying to cool this room down so it kept the call for heat longer on the northern bedroom loop which remains colder.

The system is from 2006, and according to the previous owner has never been flushed. He actually suggested doing it but wasnt sure if there was any benefit (aside from clearing up those flow gauges for a month)

hot_rod

Yes, sometimes the less you change the fluid the better. Adding fresh water adds minerals and some O2.

There are chemicals you can add that clean up systems, the two part method cleans out the gunk, then good water and inhibitors are added.

Other types of conditioners go in and lock up the dirt and crud to prevent it from settling out, but they may not clear up the water, just keep minerals in solution.

A test sample sent to a lab would give you an idea of what steps are required, if any. I know Rhomar Water has a fairly affordable boiler fluid test.

It doesn't take much scale build up to start dropping efficiencies of the boiler and heat emitters.

cms829

Well, waiting on results from our energy audit. But we did find A LOT of room for improvement in the attic. Im going to do cellulose blow in ASAP. Some sections only have 8" of what seems to be blown in fiberglass. I have to seal a lot of the exterior outlets. The north side dormer is awfully cold and you could see gaps in the insulation batts with the thermal imaging camera, or areas where theyve settled. We also have a crawl space which looks like its letting in a lot of cold air. So I am going to pull up the flooring in there and blow insulation in.

I also have to make an attic hatch cover. Though I already knew that.

Also - On the boiler. The intake pipe inside stinks like propane when the boiler isnt running. Could this be an indication that the gas valve isn't completely closing? I researched and found a few similar issues but none ever seemed to get resolved.

hot_rod

Post a pic of the energy audit, I think that would be helpful for all to see.

I had a blower door done on my old house years ago. It showed something like a 20" square opening worth of leakage. The smoke pen test was an eye opener. 1950 vintage home, all sorts of leakage.

cms829

I think hes doing that when he comes back on the 30th. He ran out of time. But I will certainly put it up when I get it for sure.

Sun was out today and by the time it brought the solar tank from 80 degrees up to 117 degrees I think we were on solar heat for like an hour. lol. Thankfully partly sunny tomorrow and Sunday so hopefully we get to give the propane a break.

hot_rod

At the very least the solar should cover DHW most any sunny day, summer or winter.

DZoro

I have seen the brass fitting coming off the gas valve loosen up, from the factory on that series of boiler. Have a technician do a leak check specifically at the gas valve connection. Does it perform a rough/rumble start sometimes?
Anyhow have a leak check done.
You mentioned solar. Is the heating also part solar?
D

cms829

Well, propane got filled today. And our bill this time is even higher at 440 bucks.

Today and yesterday have been sunny and our tank is up to 123 degrees so far. The heat has not been on all day, which is nice for a change. Sunny days are hard to come by here. I would say out of the last month its been overcast to cloudy most days with a rare ray of sun here and there. So thats not helping either.

I'll check the gas valve closer. The tech that came for the home energy audit used his detector, and after it is shut down his meter did read gas from the intake pipe. Today its been off all day so I am about to go down there and see if I still smell it. If I do now, I know its definitely leaking. The solar does preheat our DHW...and when the array gets above 110 F it does circulate through the radiant loops as well.

DZoro

Did he at least open the cover to the boiler up and do a leak check inside?
Leaking gas is not good, didn't that cause him some concern to leak check the overall system, especially to a system connected to a homeowner complaining about gas usage?
Maybe it's just me but I'd been concerned on where the gas is leaking from. The only way it can get inside the intake pipe is from inside the boiler cabinet.
D

cms829

Yea he did. The only area we could get any reading was from the intake tube. He checked all the unions of the supply line as well.

I am certainly concerned. But since the boiler had been running, he didnt seem overly concerned. Today its sunny again so Im going to let it sit (off) for a while and check to see if I can still smell anything after a couple hours. There is a new venturi on it, so its not that. I have to assume exhaust gases are getting pulled in to the intake. Not sure the vent it really proper. I'll go snap a picture of it now and post it up.

cms829

Actually doesnt look like intake and exhaust gases could mix. Maybe when its windy. But should that mich condensation be pouring out if the vent?? My wife is in the shower right now so the boiler is up to 140 as per the control. Its literally a steady stream of water. Its obviously been doing that for years, as you can see from the foundation deteriorating there. Im guessing the pitch of the pvc exhaust pipe is too great?? From what I read it should have a slight pitch back to the boiler. Seems this has the opposite.

DZoro

The exhaust should have a pitch back towards the boiler at 1/4"/ft. That termination is the reason you had to put in a new venturi. The exhaust gasses are mixing with the combustion air. Suggest terminating like the book says, and will need to slope back to the boiler in order to do so.
Strongly suggest doing a gas pressure test on the entire gas supply system, keeping the gas valve on to the boiler.
D

cms829

Good to know! Ill see what i can do to correct the vent. Have to find the book. Will have a pressure test asap.

cms829

So it looks like per the manual - The vent and intake shouldn't be anywhere near each other. Now I have to figure out how to go about correcting this. It never ends.

DZoro

You can keep the pipes exiting the wall together, Then the exhaust pipe should 90* up at least 18" and back out. Intake can have a 45* elbow.
**This configuration will need to have the slope back to the boiler or it will fill itself up with condensation and shut down.

Jamie Hall

@cms829 , you ask about doing a heat loss calculation on an existing house. Yes, it is quite possible -- and easy. Slant/Fin has an on-line calculator which is quite easy to use and as accurate as any. Worth doing.

cms829

Thank you both!

Dzoro I assume the intake on a 45* turned down? And just put a 45* on the exhaust after I bring it up 18"?

I do have to figure out how to get slope back to the boiler. Merry Christmas guys!

DZoro

45 intake and 2 - 90 on the exhaust

cms829

Copy that. Ill take care of that this week and put up a pic for inspection.