Heat Exchanger for new Boiler

[oz-plumber]

Hi all,

25 year old boiler need replacing.
Existing boiler, 220 kW doing Aged Care Facility.

I want to install a condensing boiler, but are worried about not being able to clean the system efficiently to not cause damage to the new boiler and void warranty.
The best option I can see is to have a plate heat exchanger between the new boiler and the existing heating system.
I would also have a air dirt separator installed on the existing system return piping prior to the plate heat exchanger.

Any Pros and Cons?

System to be installed - probably 2 x 100 kW boilers in cascade.

What are the chances of the plate heat exchanger blocking up?
I don't want to take the chance of installing a hydraulic separator and blocking up the boiler heat exchanger.

 

[EvilDrPorkChop]

Hi all,

25 year old boiler need replacing.
Existing boiler, 220 kW doing Aged Care Facility.

I want to install a condensing boiler, but are worried about not being able to clean the system efficiently to not cause damage to the new boiler and void warranty.
The best option I can see is to have a plate heat exchanger between the new boiler and the existing heating system.
I would also have a air dirt separator installed on the existing system return piping prior to the plate heat exchanger.

Any Pros and Cons?

System to be installed - probably 2 x 100 kW boilers in cascade.

What are the chances of the plate heat exchanger blocking up?
I don't want to take the chance of installing a hydraulic separator and blocking up the boiler heat exchanger.

Considering they block up pretty easily on a dirty system on a domestic system I would assume if the system was that bad in the first place then it'd block up. Depends how big the water ways are inside it.

 

[Gasmk1]

I have seen it done a few times best method I would fit a commercial grade magnetic filter on old system

 

[king of pipes]

I wouldn't do it bud I had 30 years of that type of work, a commercial plate heat would clog up , Ideal Evomaxs with a cascade kit was our go to system 100kw up to 900 kw , just need to bolt on a commercial magnetic filter adey do them now , also spirotech dirt and air seperator is the way to go as you say I would post some pictures but it's not working at present . Cheers kop

 

[Scott_D]

What size is the primary pipework?

 

[ShaunCorbs]

Install a cleanable / serviceable plate might cost you extra but worth it on the long run also strainer before

 

[oz-plumber]

Primary pipework 65mm.

I was going to have a air dirt separator in the return / inlet to the heat exchanger.
I have been looking for a 50mm or 65mm magnetic filter - can't source one here ( at this stage )

I don't want to run the risk of clogging up the boiler.
Either the boiler has to have a hydraulic separator installed or a heat exchanger installed.

My feelings are it's easier to replace / clean a heat exchanger, than to have problems with blocking up the boiler.

I don't feel the water in the system is too bad. The system may be 25 years old, but it has been well maintained and dosed regularly.

 

[ShaunCorbs]

Can you get Spirotech over there ?

 

[gmartine]

Primary pipework 65mm.
I was going to have a air dirt separator in the return / inlet to the heat exchanger.
I have been looking for a 50mm or 65mm magnetic filter - can't source one here ( at this stage )

I suspect it's much pricier than a 2" Spirotech but it's in your neck of the woods...a 2" Boilermag is £1500 quid here.

BoilerMag Magnetic Filters - Hydronic Heating System Filters

High performance heating system filters carefully engineered to provide lasting protection for larger heating and cooling systems. Check them out here.

www.automaticheating.com.au

 

[Gasmk1]

I have used this one in a large 7 bedroom house in bowdon 4 vailants linked into low loss header

 

[Scott_D]

Water Filters | Water Systems | Plumbing Superstore®

Water filters are highly recommended for ensuring your heating & ventilation is maintained to the highest standard. From reliable & trustworthy bran...

www.jtmplumbing.co.uk

If they would ship something like this?

 

[oz-plumber]

We can get just about anything over here.

Just can't source a magnetic filter of the size required.

We do have Sprirotech or similar products.

With Spirotech filter, would it be suitable to have that prior to a LLH connected to the boiler or would it be best to have a heat exchanger as separation?

 

[gmartine]

What about that link I posted above, that's from an Austalian company.

 

[oz-plumber]

What about that link I posted above, that's from an Austalian company.

I have contacted them.
They just import when requested.

I have dealt with this company a handful of times over the years.
Everything is in stock at the time of the order being placed and deposit paid.
Then it's not!!!

 

[Scott_D]

I have done it before with a standard 28mm magnaclean just below each boiler on the return.
LLH and then dirt separator on the system side.
Gives you three areas of collection.