What exactly needs to be insulated?

ForcedWhaaat

Hey all, happy start of the season!

I’ve got an old boiler that supplies a single pipe system. Some of the near-boiler piping isn’t as well insulated as the mains, so I am getting a vacuum at one radiator when the boiler shuts off. 

My question is, what needs to be insulated, and what does not? Obviously headers, risers, mains. But what about the equalizer, Hartford loop, dry returns, wet returns?

Also, I have some lengths of split fiberglass insulation with white tape. I want to do miter joints for the bends, etc. Where can I find white tape for the seams? HD/Lowes doesn’t seem to have it. 

Thank you!

PC7060

Regarding the tape, I use UL rate aluminum duct tape.  Works great. 

Jamie Hall

Anything which can get steam to it needs to be insulated, if possible.

JUGHNE

There are a couple of insulation web sites that will sell to you.
Sizing and ordering info. Be sure you specify iron pipe size, which is most likely what you have. You can buy kits for fittings if you want.
They include one white tape strip per length you buy.
Also sell a roll of the tape you cut as needed.

All depends upon how tidy you want the job to look.

ForcedWhaaat

Thank you. Yes iron pipe. Which sites do you recommend in particular?

delcrossv

I had good luck with buyinsulationproductstore.com. They were helpful on the phone as well.

ethicalpaul

Some of the near-boiler piping isn’t as well insulated as the mains, so I am getting a vacuum at one radiator when the boiler shuts off.

PS: You're going to get a vacuum throughout your system at shutoff no matter how well you insulate

Hap_Hazzard

You can get ductape in black and white now, in addition to the traditional gray/silver. I picked up a roll of white tape a few weeks ago for just this purpose, but I can't remember if I got it at Lowes or Homer's.

Hap_Hazzard

Jamie Hall said:

Anything which can get steam to it needs to be insulated, if possible.

If you want to prioritize, you can walk around while your heat is on with a non-contact IR thermometer (or, better yet, an IR camera, if you can get your hands on one) and see where the most heat is coming from.

ForcedWhaaat

Thank you everyone!

The IR camera is a good idea. I could also use one around the house looking for drafts. Are there any you’d recommend that don’t suck, aren’t insanely expensive, but still “good enough for a homeowner”?

ethicalpaul

I like these kind that connect to your smartphone. I have a Seek for my iPhone and it works very well. Flir is probably the leader in the market.

https://www.amazon.com/s?k=ir+camera+iphone&crid=2JYPOPI1P227M&sprefix=ir+camera+iphone,aps,79&ref=nb_sb_noss_1

nicholas bonham-carter

What make of vent is on the vacuum rad?
Remember that not only do they let the air out, but also back on burner shut down.—NBC

Corktown

This caught my eye ....

https://www.amazon.com/Klein-Tools-TI250-Rechargeable-Temperature/dp/B089QW8R9S/ref=mp_s_a_1_9?crid=2JYPOPI1P227M&keywords=ir+camera+iphone&qid=1642053173&sprefix=ir+camera+iphone%2Caps%2C79&sr=8-9