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348

I changed the expansion tank today and now I'm wondering if I need to bleed the system or is it ok to turn it back on. The last time the heater ran was during the home inspection when I was buying the place in spring.

Steps I took.

  1. Turned gas off to the heater
  2. Turned the heater off (turned off electric to the unit)
  3. Turned off water to the heater
  4. Removed and replaced expansion tank (old tank was rusty and weak at the inlet)

The old tank had quite a bit of pressure/water in it. I definitely got wet. I'm not sure about all of the components. I know one is the reducer valve for the water pressure and I'm pretty sure the other is a purge valve/bleeder, but I don't know if it's auto or manual. And if it is auto do I still need to do a manual bleed after changing the tank? If so what steps do I need to take?

Here's some pics of the system. If you need more pics of specific areas let me know.

Old Tank (pic8.co)

Reducer Valve (pic8.co)

Purge Valve/Bleeder ??? (pic8.co)

Whole System

The box on the pump is open because some water got in there so I'm trying to dry it out before turning the power back on. Any help/input is appreciated.

I plan on replacing the boiler next summer with a forced air system. At least then I'll know how to work on the damn thing if something goes wrong. Just gotta make it through this winter.

I changed the expansion tank today and now I'm wondering if I need to bleed the system or is it ok to turn it back on. The last time the heater ran was during the home inspection when I was buying the place in spring. Steps I took. 1. Turned gas off to the heater 2. Turned the heater off (turned off electric to the unit) 3. Turned off water to the heater 4. Removed and replaced expansion tank (old tank was rusty and weak at the inlet) The old tank had quite a bit of pressure/water in it. I definitely got wet. I'm not sure about all of the components. I know one is the reducer valve for the water pressure and I'm pretty sure the other is a purge valve/bleeder, but I don't know if it's auto or manual. And if it is auto do I still need to do a manual bleed after changing the tank? If so what steps do I need to take? Here's some pics of the system. If you need more pics of specific areas let me know. [Old Tank](https://pic8.co/sh/84X3Ku.jpg) [Reducer Valve](https://pic8.co/sh/oFYaBg.jpg) [Purge Valve/Bleeder ???](https://pic8.co/sh/mT5Jnk.jpg) Whole System - https://pic8.co/sh/a6FOA9.jpg - https://pic8.co/sh/XGrqg8.jpg The box on the pump is open because some water got in there so I'm trying to dry it out before turning the power back on. Any help/input is appreciated. I plan on replacing the boiler next summer with a forced air system. At least then I'll know how to work on the damn thing if something goes wrong. Just gotta make it through this winter.

(post is archived)

[–] • 2 pts

Have a boiler service check it before you fire it up.
They can be dangerous. Also, if something happens and you damage yourself or your house, the first question your insurance company will ask is who serviced it. You want the answer to be "ABC Heating and AC" not "I did it".

[–] • 0 pt

Also, if something happens and you damage yourself or your house, the first question your insurance company will ask is who serviced it.

How would they know it was serviced in the first place to know that was the issue?

They can be dangerous.

How so?

I know the heater works fine. I watched it run. It's no more dangerous than any other appliance. It's not like it's extremely high pressure. Paying someone $500+ to spend 15 minutes fucking with my heater is not something I plan on doing unless I absolutely need to. You never learn how to do anything if you're always scared and just let everyone do everything for you.

[–] • 2 pts

You never learn how to do anything if you're always scared and just let everyone do everything for you.

That's exactly what I told the cops about my garage open heart surgery business. They didn't buy it.

[–] • 2 pts

Still safer than a nigger doctor in a modern hospital.

[–] • 1 pt

If it's not a high pressure boiler, go for it. I'm all for DIY. I built a forced air heating system for my house using an on-demand water heater and two radiator type heat exchangers in an old gutted out electric furnace cabinet. It worked just fine for ~15 years

[–] • 1 pt

It's running now. Did a bunch more reading and it turns out the purge valve that's on it is automatic.

[–] • 1 pt

I had a professional work on my boiler once. He forgot to bleed the lines. Even I knew to do this. The result was the circulator pump stopped circulating the hot water. Instead, the boiler created super hot water which destroyed a pipe joint causing water to flood my basement. This in turn ruined my floor. It was quite a mess.

[–] • 1 pt

Well so far everything seems to be ok. As far as I can tell the automatic purge valve did it's job. One of my sons told me this morning he thought he could hear water dripping all night. After a quick inspection of all the radiators and the basement I came to the conclusion that he was just hearing the water circulating through the pipes. Fingers crossed I can at least make it through this winter without problems. Come next spring/summer I'll be replacing it with a forced air system.

[–] • 1 pt

If you dont get a satisfactory answer here, give AI a whirl with this question and all of the details you put here, plus the brand and model number. I've used it for a couple of projects so far and been pretty happy with the results. It'll even give you the pages where it sourced the info from. If you need parts, it can find the exact parts in stock for you, getting around shitty search engines that stores have for the websites.

I'm not saying to take it as 100% accurate, because it does make mistakes if you aren't VERY specific with your questions (sometimes it'll still make mistakes even if you are perfectly specific), but use it as a good starting point and a way to find good sources of information without having to click through pages of links from traditional search engines.

[–] • 1 pt

General knowledge style answer.

When I run into questions, or worse, problems, with anything. First thing I do is look over all the parts. Nearly everything (nearly) is marked with a name brand and model number.

Idk much about boilers, except rust can be an issue- inside and out. Keep eyes on it. Give it a general inspection on a regular basis. Listen to your system run from start up thru shutdown. An unfamiliar noise could be an early warning. Furnace or boiler, not something I want to deal with in the dead of winter. Good luck with yours.