Fuel savings...WM GV-5 vs Solo110

The Steam Whisperer (Formerly Boilerpro)

Was out today to look at a possible replacement of a Propane Weil GV-5 with a Solo 110.  Heating load is probably about 60,000btu/hr.  The GV tested out at about 89% combustion eff and clean at the side of the house.  Any experience on the savings that can be expected from this replacement.   Home has old gravity type standing radiation that appears to never get above 140F (ceiling+ wall insulated, new windows).

Unknown

Dave

Ever thought of a TT Solo 60?



But then again, who would ever listen to me. ;-)

The Steam Whisperer (Formerly Boilerpro)

Yep, but

if we add water heating and heat an addition in the home, we may need more BTU's

hot_rod

I replaced my GV

105,000, whichever model that is, with a Lochinvar Knight 80,000 when the Knight first came out, 3 years ago maybe?



Nothing else changed except I added a Hydrolink. I run 140F as I have some fintube zones, and radiant mix.



My LP consumption did drop maybe 10-15%, but we also had one of the coldest winters on record since the change out. I don't have a meter on the LP so it is hard to get an exact number.



hr

Tim McElwain

Does that GV5 have the boiler

bypass built in? If it is that model if you install a Solo 110 expect to see about a 5% difference if you make it the excellence model with DHW built in. I have a similar installation here in RI that has been in about two years. We also went with ODR and altered some of the radiation when we made the switch. It also has a low loss header.

The Steam Whisperer (Formerly Boilerpro)

Yes it does.....

it has the extra pump built in for bypass.  The installer also installed a bypass line too.  However, the piping is not quite P/S to the system.  I also noticed the return from the system tee is running hotter than the supply.  I am wondering if something ain't quite right. The fuel bills appear to be really high and they are looking to cut them down.  The rads never get very hot, so the heat load is not very high, so I am thinking the problem is in the heating plant or thermostat.   I 'll see if I can get some more feedback.  I would expect about a 20% reduction infuel usage due to the modulating burner and heavy condensing because the system runs so cool.  Unfortunately it still has the plexvent.

Tim McElwain

That bypass is not necessary as the

built in bypass will protect the unit. That boiler is not a condensing unit and should be vented with AL294C stainless. Plexvent is outlawed and should be removed before it kills someone.



It sounds like this system was not installed correctly. Some alterations to the install may bring the efficiency up to what is expected with the GV.