Baseboard radiators and polybutyl pipe

Ken Lee

I had the misfortune of purchasing a home with hot water heating and polybutyl piping that was not identified by my home inspector. Shortly after moving in, I had to replace the boiler. I now have a new Weil McLean cast iron boiler complete with a non-ferrous pump and spirovent. The installer indicated that I DID NOT require an isolation package since I had baseboard radiators rather than in floor heating and the spirovent would be sufficient to purge the oxygen entering the system.

Since the installation, I have received opinions from other parties indicating that in order to protect my boiler I still need one of the following:

- an isolation package
- a mixing valve to warm up the returning water and prevent condensation on the heat exchanger
- chemical treatment of the water

Needless to say, I am confused.

Mark Eatherton1

3 things...

If you have a non oxygen barrier tube in your system (and you do) and it is operated at a high temperature (which it is), you can do one of three things to alleviate your problem.

1. Use all non ferrous components, including boiler, pumps, air eliminators etc (too late in your case)

2. Install a heat exchanger to isolate the non barrier components from the ferrous components. This means also having to add non ferrous pumps, air eliminators etc on the non barrier side of the system.

3. Keep the water chemically treated to maintain a pH of around 8.5 This is the least expensive initially, but requires annual testing and treatment in the long run.

Although an alterntaive, eliminating the PB tubing probably isn't an option in a finished home.

As far as the low return temperature is concerned, I've not found it to be a major issue on low mass distribution systems (copper fin tube base board).

Good Luck!

ME

Floyd_5

Which WM boiler???

If you have the GV boiler you at least have the return protection built in.
If it was me... I'd be installing a flate plate, why take the chance????

Floyd

Ken Lee_2

The Weil-McLain that I have is a Gold CGa.

What's a flate plate?

Ken Lee_2

> If you have a non oxygen barrier tube in your

> system (and you do) and it is operated at a high

> temperature (which it is), you can do one of

> three things to alleviate your problem.

>

> 1. Use all non ferrous components, including boiler,

> pumps, air eliminators etc (too late in your

> case)

>

> 2. Install a heat exchanger to isolate

> the non barrier components from the ferrous

> components. This means also having to add non

> ferrous pumps, air eliminators etc on the non

> barrier side of the system.

>

This is the isolation package that I'm being quoted. It's almost the same price as the Weil-McLain installed! What's confusing is that some companies are telling me that with only baseboards, I don't really need it.

> 3. Keep the water

> chemically treated to maintain a pH of around 8.5

> This is the least expensive initially, but

> requires annual testing and treatment in the long

> run.

>

This is probably the way I'm going to go. Apparently, I'm also missing a reduced back pressure valve so I'll need to have one installed as well.

I've also been getting some banging occasionally. I'll probably need to have an air eliminator added to each zone (4 in total). Of course one company indicated that if the spirovent was working properly, I shouldn't need any. So, the first step is to have the spirovent checked. Is it supposed to weep? Is there any maintenance required?

> Although an alterntaive, eliminating the

> PB tubing probably isn't an option in a finished

> home.

>

I'd love to do this. I don't mind mending some walls. Unfortunately, the poly butyl pipes on the ground floor are covered in concrete.

> As far as the low return temperature is

> concerned, I've not found it to be a major issue

> on low mass distribution systems (copper fin tube

> base board).

>

Again, I've received conflicting information. It's not the low return temperature that's a problem, but too high a temperature of the water coming from the boiler that could damage the poly butyl pipes.

> Good Luck!

>

> ME

George_10

We have

a reasonable answer for your treatment situation. We have a specific water treatment product for hydronic systems with various metal components as well as an oxygen scavenger. Send me an e-mail or call and I will be happy to discuss your situation. You will be well advised to do something quickly as you are in the season of use now.

My e-mail is george@rhomarwater.com. My phone is
800-543-5975. Your situation can be taken care of and protected.

George Hunt

George_10

Have you looked under \"Find a contractor\"

on this site to locate professional help.