freeze protection for tt prestige

smp74

Possibly looking at having to be away for work travel during this winter. Looking for advice on the best way to protect my new boiler and system from freeze damage of thepower goes out or if equipment fails. What I have is a tt prestige 60 fin tube baseboard, modine heater and a smart40 indirect dhw. Could I drain it all out or would it be better to go with glycol? Wonder what the likelyhood of the smart tank freezing in the basement is? This is in southeast MA.

BobC

How long would you be away for? How well insulated is the house? Any piping in garage ceilings under the house? Is there someone who can monitor the house when your away?

A friend in Scituate had a baseboard pipe freeze in a garage ceiling a couple of years back when the whole area lost power for 6 days.

As to the tank freezing, how much of the basement wall is exposed to outside air? You would still have to contend with domestic water freeze up.

Bob

Jamie Hall

Note Bob's comment: you still have to [think about] domestic water freeze up.

It really depends -- a lot -- on what level of protection you are looking for.

First comments based on the idea that you are not actually closing the house, just being away for work from time to time, perhaps for a week or two at a time (if this work is that you've been posted to Iraq or Afghanistan, that's a different matter!).

I would suggest, at the very least, that you run a glycol antifreeze in your heating system. Yes, I know it's a nuisance to put in, and even more of a nuisance when you need to maintain the system. But... it's no worse than automotive anti-freeze that way, and that we do all the time. Note that if you do this, you must have a reduced pressure zone backflow preventer on you fill line... which isn't a bad idea anyway.

That will protect the heating system from freezing. Furthermore, when the power does come back on -- assuming that that is the problem! -- the heating system will come back on. Will that be soon enough to protect the domestic water? Good question... 24 hours, probably. 48? iffish. Beyond that... probably not.

If you are anticipating outages longer than 2 days, then, it might be wise to drain the domestic water when you leave. Which is a nuisance.

Or... the only real alternative is a generator. If there is someone reliable who can be counted on to be able to get to your house and start it, a manual start one would do. Otherwise, if your concern is high enough, and automatic start one, preferably on natural gas, is the way to go.

Just my thinking, here... others have different approaches!

smp74

Any possibility to drain everything and let it go cold? I will add more detail when I get back to my computer. Looking at being away for 3 months jan - mar.

Jamie Hall

Oh heavens. If you're going to be away for three months, yes, drain it all out. You may want to blow some of the pipes to make sure they're really clear. Put RV antifreeze in the traps for the plumbing -- all of them! -- and in the tanks of the water closets, unless you want to sponge them dry.

Then let it freeze.

You'll likely have a warm enough day in March in your area to get it all started up again.

smp74

Not sure if I'm reading that correctly......I am going off the deep end with thinking of draining the systems or does it actually make more sense in this situation? I do have an air compressor to blow out the lines.

BobC had commented on still having to deal with the domestic water side of things. Since this is a Smart indirect, I can't drain out the domestic side only or the inner tank will collapse. So if I do glycol I think the inner tank would still have to be full.

Basement is about 60% below grade. Basement floorplan is open, no internal walls. Foundation is not insulated. 800 sq ft ranch. Insulation is nothing fantastic.

Considering options for having a neighbor / friend lined up to hook up a generator if needed. Honda EU2000i should run the heating system for most of a day on one gallon of gas.

Jamie Hall said:

.....Note that if you do this, you must have a reduced pressure zone backflow preventer on you fill line...

Could you comment a bit further on that setup?

Perhaps drain and glycol the heating system side. Leave the Smart indirect inner tank full, but blow out the rest of the domestic lines and antifreeze the traps and WC tank. ??

Jamie Hall

In my humble opinion... if you are actually going to close the house for three months in the middle of winter in Massachusetts, drain it all down. You could leave the heat running -- with glycol -- and the Smart inner tank full, which would make starting up considerably easier (you'd have heat, which helps!). That's really your option.

I'm not sure about your local codes and the reduced pressure zone backflow preventer. Code or not, it is -- again, in my humble opinion -- required if you are running antifreeze (glycol) in the boiler and there is a pipe connection to the domestic water side for fill (it will have a pressure reducing valve on it). The purpose is to protect you in the event that -- for some reason -- the drinking water system has a pressure drop. You really don't want to be drinking boiler water, and the RPZ prevents that. Check valves would do it too -- in theory. They don't always seal... which is why, when I was a plumbing inspector, I never permitted them for that purpose.

smp74

Thank you. This definitely is helping me to come to a decision on what to do.

There is a backflow preventer installed on the feed already. This is a new system installed over this past summer.

A couple more questions:
If the heating side is glycol filled and the domestic side is shut down..... would the boiler potentially lock out on low pressure since there would be no auto fill? There is no glycol feeder at this time.

Also, how to best drain the well pump? It is a shallow well jet pump located in the basement.

SWEI

Is there a union installed close to the jet pump? If so, breaking it and opening a faucet will usually work. If not, consider installing a boiler drain or small ball valve down there.

smp74

There is a union and there are drains on the tank and on the house side of the shutoff. Pump has a foot valve so I was thinking of pulling the drain plug on the pump case so that part wont freeze.

The direction I'm heading is to drain everything, blow it out with air then pump rv antifreeze into the domestic pipes and Boiler100 antifreeze into the heating system side. Then let it go cold. That way if there is water left somewhere it won't cause trouble.