No bleeds on convectors? Any tips to bleed system?

delcrossv

Not a hydronics guy, but this is a first for me:

Small hydronic system with only drain/ bleed hose spigot near the boiler in the basement. None of the convectors have bleed valves. Should I run the PRV at higher pressure to scoot the water + air through the whole loop to purge? Any other tips?

Putting in bleed valves in the apartment is a non-starter.

Basement piping:

EdTheHeaterMan

How are the convectors connected to the 3/4" pipes? Series loop. One pipe MonoFlo® Tee. two pipe Direct Return

Is there a picture of the convector with the cover off?

delcrossv

All the convectors are 1/2" in and out. Supply is above finished ceiling so I don't have access to the supply/return loop without breaking out the Sawzall. I'm guessing 2 pipe direct return as all the emitters are 1/2".

EBEBRATT-Ed

If there are no bleeders bleed it in the basement. I would have an autovent on the air scop or somewhere to get rid of any residual air once you get the purging done.

They had to get the air out of it originally some how.

delcrossv

EBEBRATT-Ed said:

If there are no bleeders bleed it in the basement. I would have an autovent on the air scop or somewhere to get rid of any residual air once you get the purging done.

They had to get the air out of it originally some how.

EAS and Airtrol is this spring's project. Loop gurgles like Niagara Falls.

Run purge water at higher pressure/flow rate, or not?

neilc

post a better picture showing the circulator and expansion tank all in one shot with the boiler,
ceiling tank or bladder tank?
if it's ceiling then you don't want auto bleeders,

neilc

and if you're repiping,
plan to pump away from the tank

delcrossv

neilc said:

post a better picture showing the circulator and expansion tank all in one shot with the boiler,
ceiling tank or bladder tank?
if it's ceiling then you don't want auto bleeders,

Ceiling (compression) tank so I'm going with an airtrol

delcrossv

Attached pic. shows circulator. Compression tank is in ceiling. 

mattmia2

there's an isolation valve at the boiler, would have to close that then figure out how to either use the fast fill of the prv and a drain or a hose in to one drain and out another drain to purge enough water through the emitter to get it flowing. once its flowing you need to have the right fittings and piping at the boiler to move the remaining air in to the compression tank.

hot_rod

You need a really good flow to blast out a system that doesn’t have high point manual bleeders. A 1/2 fill valve may get you up around 5 gpm in fast fill mode.
A 1/2 bypass around a fill valve maybe 8-10 gpm. Same with a 5/8 garden hose connected to a hose bib.

We made a set of full 3/4” hoses, 8’ long for the flush cart, 12 gpm or more with 45- 50 psi.

1” or 1-1/4” piping, you really need 12 gpm to get a good purge.

delcrossv

hot_rod said:

You need a really good flow to blast out a system that doesn’t have high point manual bleeders. A 1/2 fill valve may get you up around 5 gpm in fast fill mode.
A 1/2 bypass around a fill valve maybe 8-10 gpm. Same with a 5/8 garden hose connected to a hose bib.

We made a set of full 3/4” hoses, 8’ long for the flush cart, 12 gpm or more with 45- 50 psi.

1” or 1-1/4” piping, you really need 12 gpm to get a good purge.

Thanks! It looks to be all 3/4. Hopefully the PRV in fast fill will get it done enough. Else it's a bypass.

jumper

EBEBRATT-Ed said:

If there are no bleeders bleed it in the basement. I would have an autovent on the air scop or somewhere to get rid of any residual air once you get the purging done.

They had to get the air out of it originally some how.

A proper fill station gets the air out. Bleeding terminals is time consuming. I used to offer to sell or to rent stations or to perform that task. Another of my numerous business failures.

mattmia2

It does look like there are some valves to further isolate sections but more air will come out as the fresh water is heated so unless it is set up to encourage that air to go back to the compression tank you will never get all the air out.

delcrossv

mattmia2 said:

It does look like there are some valves to further isolate sections but more air will come out as the fresh water is heated so unless it is set up to encourage that air to go back to the compression tank you will never get all the air out.

Yes, two loops on that one. 

I agree,  really needs an Airtrol.