I had an electric hto water heater installed to cut down on my oil usage and when my oil furnace was cleaned in the summer, the tech said the heating loop and the furnace need to be drained so I can keep the oil off for the summer. So he drained it.

Now it's time for heat again so I called to ask him how I can refill it and he no longer works for the company.

My heating system is a single zone, oil fired furnace. The house is a small ranch if that matters.

I have a few questions:
How do I refill everything?
Should I include a corrosion inhibitor?
Can I do this myself or should I get someone? (It doesn't seem hard but maybe there's more to it than meets the eye.)
Do you think any damage was caused by this? Could my firnace have been rusting the whole summer?

Thanks in Advance!

 

Thats just crazy!!!.

You will need to open up the fill valve on the boilker to fill the system. Then you need to purge the air out.

But you need to specify what type of heat emmiters you have. Possibly there are bleeders open, and or drain valves open. You will need to make sure everything os closed before you fill.

To purge the air there are steps to take. It will be better if you can take pics from all angles of the boiler. If we can see the system we can guide you.

Also there is a way to disable the low on the aquastat to make it a cold start boiler, so you can save more on fuel.

Yes you can DIY. I dont think any real damage occured, but the idea is not to add new water to the boiler. Water contains oxygen, and thats what causes corrosion.

Add an inhibitor??? What type of feed water do you have? Well, city water?

Again, take pics. Boiler, controls, everything.

Others will chime in and will be glad to assist.

Mike NJ

 

I'll take pics when I get home tonight. For now, here is a little diagram I drew up. There are what look like little bleeders under the elbows to each radiator. I would think I would get the air out of these.




I have well water.



After I get this taken care of, what do I need to do next summer when I shut the oil burner off? Just turn the switch off?

 

What is the PH of your water? Any kind of treatment for the well water?

You may want a inhibitor to buffer the PH, etc....

Fill the system and purge the rads. Throw the unit on and see if it circulates. If not close the valve on the return on the right of your pic and bleed from the boiler drain above it. ( Thats what it looks like in the pic )

This will force the water in the boiler and around the loop to push out any air.

You may need to raise the pressure with the fill lever to help it along. When you have a steady stream of water you should be good to go.

Verify you have around 12 psi in the boiler and start her up.

You probably should adjust the aquastat or disable the low, otherwise your boiler will keep temp for the old hot water coil and waste fuel.

Mike NJ

 

Here is a copy of the water test we had done on the well last year.



Uploaded with ImageShack.us

The water is hard but that is its only fault. Do I need any additives?

Why would I disable the low on the aquastat and how? Could I just turn it all the way down? I heard something about not going below 140 or acid could buildup inside and create corrosion? Is that true?

 

Your water is hard but the PH is good. I would just fill it.

What is the model aquastat?

The condensation issue is when your feed and return temps vary by a wide spread. I believe more then 40 degree delta T.

Possibly you have a bypass piped on your boiler? Possibly you did not draw it in your drawing?

Lowering the aquastats low all the way will help on saving fuel. But it will still maintain that low temp even if there is no call for heat. Disabling the low will make it a cold start boiler. meaning if there is no call for heat, the boiler will not kick on, and will cool to ambient temp.

But there are pros here that know this stuff and will help. They all should be on later today.

Mike NJ

 

Mike, Thanks for all the help so far. I will make a more detailed drawing when I get home. I'm pretty sure I understand what you are saying though so I will try filling the furnace and system.

My main question now is, Do I need a corrosion inhibitor? Are inhibitors typically added to the heating loops?

Also, What do I need to do when the winter is over? Just shut off my oil burner?

 

I feel nothing should be added to a boiler. Others may have different opinions.

Yes. As long as it dont leak. That could be a possibility why the guy drained it. A warm start boiler likes to be warm sometimes. Making it a cold start they may leak some until they are warm.

You will know when you fill it.

Mike NJ

 

You should not drain your entire system for the summer. Just turn the switch off and it will be fine. Converting your boiler to cold start is a good idea to save fuel.

 

Ok so I refilled the system but the circulating pump has a humm to it. It seems like there's air in the line. I noticed an auto vent near the expansion tank. If I let it circulate long enough will the air bleed out?? I tried feed and bleed and it seemed to help but did not cure the problem.

 

Yes circulaters humm.

Do you hear water moving through the pipes?

Yes the air should purge if that auto vent is working. Is the cap loose on the auto vent?

Tighten it and then loosen it a turn. You should hear air when it purges.

Whats the pressure gauge read?

Mike NJ

 

Yes I hear the water moving through the pipes and it's quite annoying. I know it did not do this before. It's mainly only in one room that I hear it so I will try isolating the 2 loops and forcing everything through that loop for a period of time to see if it clears up.

The boiler does not leak.

 

It should come out with time. Especially when you fire it up.

Adding more water may be adding more air. If you got it circulating leave it.

Possibly the air vent aint working. Did you loosen the top of the air vent?

What is the PSI at the boiler?

I like to raise the pressure slightly with multi floor or large water capacity systems. Higher pressures IMO compress the air bubbles better for disapation.



Mike NJ

 

The pressure in the boiler is about 15psi. Our house is a small ranch with an unfinished basement. I had it fired up last night and circulating. The vent is working good. It's really only in the one radiator that we can hear it a lot. I will try forcing all the flow through there.

I did not loosen anything on the air vent. It seems to be forking good. I can hear some gurgling and air coming out when circulating.

 

The air will come out, be patient.

Hey did you check and make sure to boiler kicks off at proper temp?

I check every season to make sure the aquastat shuts off at the correct temp its set for. Typically 180F.

Mike NJ

 

My aquastat has a high, low, and diff. the way I understand it is that the low is where the circulator pump kicks on if calling for heat, the high is where the furnace shuts off, and the diff is the number to subtract from the hi to get the temp where the furnace kicks on at. Is ths correct?

i was playing with it last night and no, the hi on the aquastat seems to be different than the gauge on the top of the boiler. The gauge seems to be about 10F-15F high. I set the hi at 160 and the diff at 25. Which one is most likely wrong? The gauge?

 

I would say the gauge may not be accurate.

I believe since you have a seperate HWH set the low all the way down. 100F?

Set the high 170-180F

Set the diff to its lowest 10. You have no need to keep the circ off for HW so I believe 10 is the preferred setting.

Trooper can perhaps add to this.

Also at a 180F high on the aquastat and a call for heat what does the gauge read after boiler kicks off?

Also you may want to disable the low altoghther. Post the model of the aquastat.....

Mike NJ

 

I know the aquastat is a honeywell but couldn't find the model. It has a high, low, and diff.
I finally got a chance to take some pics.

 

Well I read this: Aquastats: Setting & Wiring Heating System Boiler Aquastat Controls, how to set the HI limit LO limit and DIFFerential dials on controls like the Honeywell R8182D Combination Control Aquastat

And it really helped me understand how aquastats work. I now understand why you guys were saying about disabling the lo. How do I do that?

 

The diff keeps the circ off longer for a HW call I believe.

You said you have a seperate HW heater correct?

[NJT edit- as I said below... reservations, sorry, and only half the job]

Turn your hi to 170f-180f.

If you are not going to disable the LO then do as described in post #17.

Mikr NJ

 

Your aquastat appears to be an L8124A,C model.

Can you get a closer, clearer, in focus, better lighted, shot of the lower right quadrant of the aquastat please? I want to see the terminal designators... particularly where that white wire that appears ready to fall off the terminal.

Something don't look right there, I just wanna be sure.

Removing that blue wire is only half the job...
I have my reservations about posting any modifications to an aquastat on the forum.
Private messages? what I don't see can't hurt me...

 

The Aquastat works like this the low is to protect the boil from condensation by preventing cold water below 120f from circulating it is recommended set at 140f if the water is below this and there is a call for heat the burner will come on and the pumps waits until the water temperature satisfies the low setting and then comes on .The Diff. is there to prevent the cir. pump from short cycling .The High set 20f above the Low turns the burner on during a call for heat ,If the blue wire, is pulled the burner will come on only during a call for heat TTare crossed therefore the boil will go cold and thus a cold start .The only reason to keep a boiler on standby is when D.H.W. is provided by the boiler coil connected directly to the taps .During the summer a cold start boiler in a damp basement is in danger of becoming wet and when soot is wet it becomes sulphuric acid good by boiler.A way to prevent this is to hook up the Electric hot water tank to the boiler coil use a stainless steel pump with check valve a cube relay 24 volts to start pump and burner this will circulate domestic water from top of tank through coil back to bottom of tank to prevent boiler condensation also a new electric hot water tank switch and 24 volt transformer is needed to power up system, this system can provide some heat to home when burner is off also boiler can be off during summer to prevent over heating home just to make D.H.W.

 

Trooper, your inbox is full

Also, my circulator pump is 'howling' now. I can't hear it when I'm right next to it but when I'm upstairs, it's actually somewhat loud. I don't think this is normal since it did not do this last year. Could this be from the air in the system? Somehow I doubt it is... I guess the good thing is that it does not seem too difficult to replace one of these. This is my major problem now.

 

Max, I emptied it, try again...

It's possible that the pump can make strange noises if run DRY, but even it there is air up higher in the heating system, the pump won't be dry...

 

Well after running for a few days, the leftover issues seem to have cleared up! The pump does not 'humm' anymore and the air in the lines is all but gone. Thanks for all your help guys!!!