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Aquastat on oil furnace set improperly leading to multiple issues/Please help, need advice

NJJRH Member Posts: 5
edited January 2016 in Oil Heating
First off, thanks for letting me be apart of this forum and I hope I can not only resolve this issue but get advice on how to handle it. I apologise in advance if this is lengthy but I want to be thorough in my explanation.

So this all started back in December 2015. I have an oil furnace and have been using the same company(family owned and operated/Father owner/Two sons are the techs) for roughly 6 years but have not always been satisfied with the service. Like clockwork I scheduled my annual furnace tune up. I have had no prior issues with my furnace until this time. After the son came out and had finished with the tune-up and left I also had left to pick up my kids and run some errands. When I came home that evening (being acquainted with how my furnace sounds) I knew something was wrong as the furnace was clicking on and off very abruptly I then heard the sound of water so I ran to the Boiler room and sure enough there was water on the floor and it was dripping from the pipe that leads to the Pressure/pop release valve on the furnace. I cleaned it up, put a bucket under the valve pipe and called the oil company/tech service and left a message. They advertise as 24hr but they never get back to me in the evenings.

When I finally spoke the next day with the owner he walked me through troubleshooting the problem. I advised him the pressure gauge was higher that normal(makes sense as why the release valve popped) and then proceeded to remove the cover to the aquastat. at this time I advised the owner that the high/low on the aquastat was set improperly at 180 low 180 high when I know that it is always set at low 160 high 180. No one else ever touches these settings or the Aquastat except for them. The owner did not say much about that. i reset the low back to 160 and the owner said he would come out to take a look. The pop release valve had to be replaced and within the week I had to call back because the heat would not come on, only to find out that the Aquastat now had to be replaced. Again, I reiterate I had no prior issues before my annual tune-up and here I was replacing two parts(one the day after the tune up and the other within a week later). After the aquastat was replaced I noticed that evening there was water back on my floor(just a few drips) I noticed that this only happens when I run multiple zones at once and again I never had a problem prior to this.

Unfortunately due to the fact I am dealing with another issue(zoning, property damage issue) with my house I have not been able to call back yet to rectify this issue and it is now a month or so later. I was under contract with this company so I never payed a service fee. I was billed for these two parts since the pop release valve is not covered but my contract shows the Aquastat is covered. I remembered him stating that it wasn't but under COVERAGE it lists "Aquastats". I am looking to contact the company in question to dispute these issues and the fact that I feel and I know! that his son had set my aquastat improperly and I shouldn't have to pay for his carelessness. On top of that I still can't run multiple zones without getting water from the pressure/pop release so either the aquastat he installed is no good or something else might have burnt out like the pressure gauge. The new aquastat is set to 160 low 180 high and the differential is set to 10 but I am not sure if that is correct for the Diff.

Can anyone tell me why after these two parts were replace i would would still get water out of the pop release? I usually notice it when running multiple zones. Also what is your opinion on the fact that I am being charge for two items that prior to my tune up were fully functional. I am really frustrated more about the dishonesty and this was not the first time this has happened with this company on a routine tune up(twice before with his different son but different circumstances and nothing luckily had to be replaced.)

Any thoughts opinions and help is greatly appreciated as I am sick to my stomach about this.

Thanks in advance for you help.


  • Jamie Hall
    Jamie Hall Member Posts: 18,958
    Well, first off I have no opinion on the charges. That is strictly between you and the company involved.

    The aquastat set at 160/180 may be the correct settings. If it never gave you trouble before at those settings, we'll leave that be for the moment.

    The temperature/pressure relief valve could be opening for one of two reasons: over temperature or over pressure. That's what it is designed to do -- and, if it is operating or weeping, it really should be replaced once the underlying problem is corrected. They aren't really one shot devices, but they are not that expensive and they are an important safety.

    Which leaves us with the question of which of the two possibilities for its opening is correct.

    Question 1: does the boiler shut off when the aquastat reaches its upper limit? Does it then pause for a while while the water temperature drops, and then turn back on? If it does, it's probably not an over temperature situation.

    So -- perhaps over pressure. What does the pressure gauge read when the system is cold? What does it read when the system is running? Can you get those numbers and get back to us?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    NJJRH Member Posts: 5
    edited January 2016
    Thanks Jamie for replying. First, yes 160/180 is the proper setting for the high low for my furnace/aquastat. The problem started after my tune up I noticed the aquastat was changed to 180/180 for hi/low which from my understanding would be a conflict.

    I would have to get back to you to check the pressure gauge when the system is cold as we have been running the furnace frequently.

    Right now I checked the furnace and even though the aquastat is set correctly to 160/180 the Pressure Gauge shows the furnace shutting or I should say pausing closer to 195 then it drops to a little under 180 before the furnace goes back on so it never even drops to the low/160. the PSI is between 20 or 25. But that is with only one zone running, if I were to turn the upstairs zone on at the same time my lower level zone is running that is when I will start to get the water in the bucket but I haven't seen what the gauge is at when both zones are running and quite frankly I am afraid of running more that one zone in fear of being without heat completely on such a cold night.

    So does this mean the pressure gauge would be next on the list to be replaced? Thanks again for your reply and helping me out with this problem.
  • Jamie Hall
    Jamie Hall Member Posts: 18,958
    No, it wouldn't necessarily mean the pressure gauge should be replaced. Don't shoot the messenger! It may be that the system pressure itself is too high -- either cold pressure or running pressure. Somewhere on the system there is an expansion tank, and it's purpose is to limit the pressure change between hot and cold. If it get full of water or fails, it can't do that, and may need to be either recharged -- or replaced.

    Further, there is perhaps a fill valve connected to your water supply. It should be set to the cold system pressure, but if it is leaking or not functioning properly it could make the system cold (and hence hot) pressure too high.

    So... we need to know what the cold pressure is, as well as the hot.

    I'm not really happy with the aquastat turning the boiler off at 195 when it is set at 180. Is there any way you can really check what the water temperature really is?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,689
    I think you oil company owes you a better explanation of what they did when the did the annual service.
    If I had to guess, I would say the aquastat was turned up to allow the burner to run longer for a combustion test and the tech forgot to turn it back down. It's possible that it's not sensing the temperature properly and rising up to 195. It's also possible the differential was changed too. But you do deserve an exact technical reason why it needs to be replaced.
    Too much pressure. This goes back to the annual service. Was the expansion tank drained? It's possible they drained a logged (or thought it was logged) expansion tank. This allowed fresh water into the system and the air may not be properly bled from the system. This caused the relief valve to pop, and maybe not properly seat. Along with this, now the feed valve opened to allow in water and may not have seated properly. So more water keeps getting fed into the boiler, raising pressure, popping the relief valve-and the cycle keeps repeating.
    Turning on the other zone and having it blow the relief is an air problem
    You just need someone experienced to check/correct these issues to return the system to the way it was before the annual service.
    NJJRH Member Posts: 5
    Yes! I am familiar with the expansion tank and funny you should mention that as possibly being the issue as I thought that might have been a problem last month when this all started because it felt abnormally hot (as it was probably filled with water at the time) But the tech said it was fine. I had the tank replaced some years ago and they explained sometimes the mesh inside can eventually break.

    I am not familiar with the fill valve, is that the same as the automatic water feed? the one that looks like a bell? I can definitely say there isn't any leaks. only time i see water is from the pressure release valve and that is if I ran multiple zones at the same time.

    Not sure how I would go about checking the water temp.

    I too am not happy with the boiler pausing at 195 when it should be 180. We have a big storm coming this weekend and I will most likely have to find a new Tech to come out and speak with the old Tech as well.

    Thanks again Jamie i really appreciate the help.
    NJJRH Member Posts: 5
    edited January 2016
    Thanks Steve for your help. I agree. i don't think the tech did this on purpose but I also don't think I should pay for his honest mistake either. No the expansion tank was never drained.

    Can you explain further on what you mean by an "air problem" when blowing the relief running multiple zones? Could you tell me what steps should be taken to correct that?

    Thanks again for your help Steve, it is much appreciated.
  • GW
    GW Member Posts: 4,542
    Yes that's unfortunate. At least you have an arrangement where you're paying next to nothing ( unless I read too quickly). We don't sell fuel, and don't offer the coverage plans you indicated.

    It's either a wildly crazy fluke or the dude was meddling with your sysyem, which quite frankly is hard to digest (for me at least).

    We have done work where the call would come the next day with an indication that "it was fine before your service guy was here ". Those are some pointy words and one must use some caution while conveying these opinions.

    Sometimes we make a mistake, other times it's a new problem, just bad timing making us look bad. We all could probably ramble off a hypothetical story or how something could go wrong amd bad timing taints the story line.

    It seems like the expansion tank may possibly be low on air.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
    NJJRH Member Posts: 5
    edited January 2016
    GW thanks for your post. Yes I think you might want to go back and read again. i wouldn't call over $400 paying next to nothing especially given the circumstances. I am not one to just point fingers. I am not an oil furnace tech either. But as a homeowner I have learned as I go and I have had items replaced before on my furnace like the Aquastat, Pressure release valve, expansion tank, fuel pump, bearing assembly etc.. I have no problem opening my wallet when something breaks down due to normal circumstances.

    If you are going to tell me that a tech leaving my aquastat set to 180/180 as the hi/lo is not going to have a damaging effect then I have to question your knowledge on this matter.

    Not to mention like I said in my original post, this is not the first time something like this has happen after a routine furnace tune up with this company.

    As for the arrangement, yes I was under contract with them at the time and up until this month. But as I said in my original post I am being billed for the pop release which is not covered on the contract so I can understand why they would send that. But it shows Aquastats clearly stated on my contract under "Coverage" and yet I received a bill for that too with a service charge to boot which under contract I have never paid as part of the agreement. So even the billing is fubar. I never paid service fees prior to this incident I am assuming this is an honest mistake too. I will be contacting them but I will most likely have to call another company out to correct this issue.

    I am sure it wasn't done with malicious intent but no customer should ever have to pay for a mistake made by the company it is already paying in advance yearly for services provided.

    I agree with you on the expansion tank but that's about it.
  • Aaron_in_Maine
    Aaron_in_Maine Member Posts: 315
    The expansion tank is on its way out that is probably why the relief valve is popping off. The aquastat just made the symptoms show themselves. I have seen an aquastat set at 200/200 and not caused any damage to the system. It was a cleaning and it was the first time I had ever been there so I don't know how long it had been like that. But everything ran fine after I left.
    I think it is just a bad expansion tank and bad timing. I always tell people that if I could predict when electronic parts were going to crap out I wouldn't be doing this job I would be rich and living on an island somewhere.
    Aaron Hamilton Heating
    [email protected] yahoo.com
  • enalkarion
    enalkarion Member Posts: 7
    edited January 2016
    I have to agree with Aaron. I've done commercial HVAC (or ACRH as I think its referred to as now for 10 years and have made that same aquastat setting mistake early on in my career, and it will cause the boiler to run way more than needed. It sounds like you had a failing expansion tank that finally let loose causing the relief valve to pop. Its been my experience that they rarely reset and seal unless they are fairly new. There is a temp/pressure correlation, but I doubt the aquastat settings caused your relief valve to fail. I wouldn't advise it, but its possible for a boiler to run at 220 degrees and 10 psi and most likely your relief valve is set for 30 psi. Don't get me wrong he didn't do you any favors by forgetting to reset the aquastat, and you shouldn't have to pay for a service call for that, but those settings wouldn't cause the aquastat or the relief valve to fail. If your contract says aquastats are covered and it turns out to be faulty you sir are owed an aquastat. But in my own house even at the 160/180 it always overshoots, especially if the main zone hooked to the aquastat is calling. No 2 temperature measuring devices read the same unless they are calibrated to do so. They may just both be off by a few degrees. If it were me I would adjust the high and watch where it cuts off at and adjust accordingly. It sounds like you had multiple problems with your system that reared their head after a foul up with the maintenance. expansion tanks, pressures, temp settings, zone powerheads, and circulators are all things I check on a boiler maintenance. I hope you get the matter resolved with your ( I'm hoping former) techs and find someone who at least can provide you with a checklist or proof of what was done.
  • burnerman_2
    burnerman_2 Member Posts: 297
    Do you use the boiler for hot water?? for domestic use? could be a pin hole in the coil