Oil (Tankless DHW) to Electric advice needed


  #1  
Old 02-22-15, 07:16 PM
M
Member
Thread Starter
Join Date: Oct 2007
Location: Eastern CT
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts
Oil (Tankless DHW) to Electric advice needed

A relative of mine (on fixed income) is facing the tankless DHW blues and I'm trying to help her decide if it makes sense to get a new coil or to abandon it for an electric DHW tank. The house is in middle CT with well water. The Peerless boiler was installed circa 1987 and is over sized for the small house. Some of the bolts for the coil look rusted and likely to be uncooperative. I'm guessing it will be a $1,000 job for her plumber to replace it. In addition, there is no tempering valve so the water is close to boiler temp which, in my opinion, is dangerous. So add further cost by adding a tempering valve.

I have read in a few places that these tankless coil set ups are one of the least efficient ways to make hot water so I'm reluctant to see here spend the money to replace the thing. The boiler works fine otherwise so replacing the whole thing doesn't make sense either. Installing a 40 gallon electric tank seems to make sense here.

I do need to check what the lower limit is on the boiler control. If it can't let the boiler shut down then we can manually shut off the power. Is this harmful to the boiler?
 
  #2  
Old 02-23-15, 07:20 AM
P
Temporarily Suspended
Join Date: Jul 2008
Location: NY
Posts: 10,982
Likes: 0
Received 0 Likes on 0 Posts
Some people don't have good things to say about the tankless system. However, before I put in a 40 gallon electric hot water heater, I would try to calculate how what the cost of that would be per month. Electric is efficient but not cheap. Does the house have natural gas?
 
  #3  
Old 02-23-15, 10:08 AM
M
Member
Thread Starter
Join Date: Oct 2007
Location: Eastern CT
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts
Nope it's oil so propane would be the only other option.
 
  #4  
Old 02-23-15, 10:53 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,538
Likes: 0
Received 8 Likes on 6 Posts
Electric water heater can be competitive in cost to operate against oil and propane, not against natural gas... yet.

I did some figuring last year and I think I concluded that with oil at 3.65 (at the time) and electricity at 0.12 kWH the cost was about equal to run.

Don't forget the cost of an electrician to run the 240VAC line to the location of the water heater.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: